Lasers are commonly used to mark, etch, cut and weld a wide variety of materials in automotive plants, packaging lines, medical procedures, aerospace manufacture and many other applications. It seems that there is a new use for lasers every day. Lasers can offer an alternative to traditional processing methods. If coupled with the right Local Exhaust Ventilation (LEV) systems, lasers deliver excellent results in terms of precision, machining time, flexibility and performance. To comply with international health & safety regulations, LEV’s are required or recommended for use with most laser operations in order to protect personnel and to enhance the performance of the laser system itself.

What happens in laser processing?
When a laser beam is applied to the surface of a material, several conditions can occur. High temperatures that are generated cause the air near to the contact point to expand, generally back in the direction of the lens. The laser beam causes incineration, vaporization, melting and softening of the target substrate. Rapidly expanding gases pick up and carry the removable particles and droplets at relatively high velocities away from the substrate. The contaminants released consist of a wide variety of gases, in some cases noxious i.e., benzene, phosgene. They also consist of the products of complete and partial combustion including possible oxides of the base material. Stainless steel, for example, releases Chromium and Nickel, which can cause chronic toxicological effects such as liver/kidney disease and cancer.

It is critically important that you are aware of the emissions produced during your specific application as many laser processes produce extremely harmful and even toxic fumes. The following is a list provided by Purex, who manufactures digital and analog fume extraction solutions for laser applications.

Common Substrates, and LGACs

Non-Metals

Metals

For an expanded list: Contact richard.riffner@purex.co.uk  630-465-2412

There are a number of important items to take into consideration when evaluating LEV’s for your application. Use these as a baseline when evaluating solutions.

Flow Control

Over time filters become saturated and blocked from captured particulate. As blockage occurs, the flow rates may drop and if not manually monitored, gases/particulate will not be captured and eliminated. LEV’s with intelligent Flow Control automatically monitor airflow and adjust motor speed to keep the extraction rates at the required speed throughout the life of the filter. This ensures proper air quality while preventing downtime and expensive damage to equipment caused by loose particulate.

Air Monitoring

How do you know that your system is capturing what it should? Consider a solution that provides feedback and insures that the air returning to your workplace is safe.

Filter Status

It is important to change filters when needed or you risk having an LEV that no longer operates at the optimum level. On the flip side, changing them too soon can be expensive. Look for a system that provides feedback regarding filter status which produces a safe work place while reducing filter costs..

OSHA citations have now been issued relative to lasers using the authority vested under the “general duty clause” of Public Law 91-596; the Occupational Safety and Health Act of 1970. Once you pinpoint the emissions produced in your process and integrate an ample LEV, you can help insure the safety of your workplace while extending the life and up-time of your laser systems.

On the back of excellent sales performance throughout 2011, the Productronica exhibition was an outstanding success for Purex International and a great way to end the year.

Purex set out to launch new products and to showcase it's fume extraction technology at the show and were rewarded with new distributor agreements, machine sales and a great response by new and current customers. Many key distributors which were at the show themselves also exhibited Purex equipment on their stands.

Featured at the show was the new FumeSafe machine which actively removes solder fumes from hand soldering processes by using on tool extraction that does not cool the iron tips. The FumeSafe can cater for up to 15 soldering irons and uses high performance 4-stage filtration to remove solder fume from the air and return clean, purified air to the workplace. This means that it is no longer necessary to use vent to atmosphere extractors which need holes to be cut in the factory roof and walls.

Leanne Kilcommons & Sam Mawhood with the Purex Sentinel

Also at the show was the new 2tiP unit which works on the same principle as the FumeSafe and provides on tool extraction for up to two soldering irons, it is ideal for two people working on a bench.

Purex also exhibited their more powerful machines such as the 1500i which can extract fumes from wave and reflow ovens as well as multiple extraction arms.

Jon Young, Sales & Marketing Manager for Purex, commented: "If anyone would have told me before the show that we would sign agreements with a lot of excellent new distributors, meet countless end users seeking fume extraction solutions, have requests for trials with several major OEMs, sell machines off the stand and meet current customers from all over the world on each and every day of the show, well, I would have been sceptical to say the least! However Productronica delivered all this and more."

"We were overjoyed at how busy we were, all our visitors loved the stand and appreciated the advanced technology we demonstrated in our systems. I would be suprised if the show does not pay for itself 10 times over very shortly."

For further information contact us.

Purex Staff with a Key Customer

A Bit of Help From Our German Distributor Renate

 Andy Easey, Purex General Manager with Customer

Purex International have run dress down Fridays each week where staff pay a contribution which has been donated to Children in Need.

Children in Need provide grants to projects in the UK which focus on children and young people who are disadvantaged. They are local to people in all corners of the UK and support small and large organisations which empower children and extend their life choices.

The grant programmes are open all year round for applications, with a focus on allocating the money to deserving projects 4 times a year. To find out more about grant programmes, to apply for a grant or to hear how some children's lives have been changed for the better, visit http://www.bbc.co.uk/pudsey/

The Rotherham based firm recently received accreditation from SAFEcontractor, a programme which recognises very high standards of health and safety practise amongst UK contractors.

Purex is principally involved in the manufacture of high performance fume extraction systems.

Specialising in the coding and marking, electronics manufacture, laser engraving, and printing industries and with a multi million turnover, Purex’s most recent clients have included major players such as Coca Cola, Nestle, BAE and many more.

The company’s application for SAFEcontractor accreditation was driven by the need for a uniform standard across the business. George Lindley of Purex said, "SAFEcontractor accreditation is expected to enhance the company’s ability to attract new contracts and its commitment to safety will be viewed positively by its insurers when the company liability policy is up for renewal."

SAFEcontractor is applicable to most sectors although it is particularly relevant to food manufacture, property, facilities management, retail and leisure sectors, all of which are big users of contract services.

John Kinge, Head of Risk at SAFEcontractor said, "Major organisations can no longer run the risk of employing contractors who are not able to prove that they have sound health and safety policies".

"More companies need to understand the importance of adopting good risk management in the way that Purex has done. The firm’s high standard has set an example, which hopefully will be followed by other companies within the sector".

Under the SAFEcontractor system, businesses undergo a vetting process, which examines health and safety procedures and their track record for safe practice. Those companies meeting the high standard are included on a database, which is accessible to registered users only via a website, www.safecontractor.com

Employer-organisations who sign up to the scheme can access the database, enabling them to vet potential contractors before they even set foot on site. These employers agree that, as users of the scheme, they will engage only those who have received accreditation.

Over one hundred and fifty major nation-wide businesses, from several key sectors, have signed up to use the scheme when selecting contractors for services such as building, cleaning, maintenance, refurbishment or electrical and mechanical work.

The new Kanban racking system allows additional storage for filters and connection kits and by utilising vertical storage, this system frees up a large amount of manufacturing floor space which is required for increased machine production at Purex.

Production Manager, Paul Brooksbank, says “This racking is an excellent solution for the company as we expand due to increased demand for our products. With the racking we have freed up extra space for cellular manufacturing.”

Paul continues, “Introducing the new forklift truck and racking system has enhanced our delivery, storage and despatch functions. We can now offer world class services including “Same day despatch” on many filters and spares and “One Day” lead times on popular machines."

Expansion continues at Purex Fume Extraction Systems with two new sales engineers being employed earlier this year; the latest recruit is Ashley Horrocks - 19, employed in the role of stores operative. Ashley was previously unemployed before joining Purex, but showed confidence and excellent interviewing techniques to impress. Paul explains “What impressed me the most about Ashley was the fact that he completed training and qualifications whilst unemployed to get his forklift truck and counter balance licences.”

For more information contact +44 (0)1709 763000 or visit www.purex.co.uk

Neue Investitionen bei Purex Fume Extraction Systems

Purex International, Hersteller von Dampfabsaugsystem aus Rotherham (Großbritannien),hat 32.000 £ in ein Kanban Hoch-Regalstapler-System investiert, um zusätzlichen Lagerraum zu schaffen, der aufgrund der gestiegenen Nachfrage nach den Produkten des Unternehmens nötig wurde.

Das neue Stapelsystem von Kanban schafft mehr Lagermöglichkeiten für Filter und Anschlusskits und durch eine vertikale Lagerung macht dieses System viel Nutzfläche frei für die Herstellung, was aufgrund des gestiegenen Anteils der Maschinenproduktion bei Purex nötig ist.

Paul Brooksbank, Produktionsleiter, dazu: „Diese Stapelung ist eine ausgezeichnete Lösung für das Unternehmen, da wir aufgrund der gestiegenen Nachfrage expandieren. Mit dieser Stapelung wird mehr Platz frei für die Zellenfertigung.“

Brooksbank weiter: „Die Einführung des neuen Gabelstapler-System hat unsere Leistung bei Lieferung, Lagerung und Versand verbessert. Wir können jetzt bei vielen Filtern und Ersatzteilen Weltklasse-Service wie Versand am selben Tag und Durchlaufzeiten von einem Tag bei gefragten Maschinen bieten.“

Die Expansion von Purex Fume Extraction Systems setzte sich in diesem Jahr mit der Einstellung von zwei neuen Vertriebsingenieuren fort. Der jüngste Neuzugang ist Ashley Horrocks, 19, für die Lagerarbeit. Vor der Anstellung bei Purex war Ashley arbeitslos, bewies aber Selbstbewusstsein und überzeugte mit ausgezeichneten Gesprächsfähigkeiten. Brooksbank erklärt: „Am meisten beeindruckte mich an Ashley, dass er während seiner Arbeitslosigkeit die Ausbildung und Qualifikationen für den Führerschein für Flurförderzeuge erworben hat.”

Mehr Informationen unter +44 (0)1709 763000 oder www.purex.co.uk

When soldering without effective control, solder flux fume is likely to enter the breathing zone of the solderer causing the development of occupational asthma, long term carcinogenic diseases, damage and irritation to the respiratory tract, and other serious complaints.

The new, compact “FumeSafe” fume extraction unit from Purex can protect workers by extracting solder fumes from the tips of up to 15 soldering irons without cooling the tips. The FumeSafe is precision made from stainless steel and features a powerful auto sensing dual voltage blower (230V to 120V) enabling usage not just in the UK and Europe, but worldwide.

An activated carbon filter is used to remove harmful gases from the solder flux fumes, along with a sub-micronic (HEPA) filter which removes 99.997% of particles down to 0.3 microns before clean air is returned to the workplace. Key features of the FumeSafe include speed control, low capital and running costs, simple installation, filter blocked alarm and LED, and quick change pre-filters to deliver longer filter life.

Solder fume from an iron without extraction	Solder fume from an iron with extraction

Other advantages include the fact that the machine is quiet in operation and easy to relocate. The machine is also supplied with three iron kits and pipework.

For more information about the new FumeSafe click here or contact us on 01709 763000 or email us at purex@purex.co.uk

Neue Purex-Absaugmaschine für die Lötspitze

Purex International, aus Rotherham (Großbritannien), hat eine neue Maschine zum Absaugen von Dämpfen entwickelt, mit der verhindert werden kann, dass Arbeiter gefährlichen Lötdämpfen ausgesetzt werden.

Beim Löten ohne effektive Kontrolle ist es wahrscheinlich, dass Dämpfe des Lötflussmittels vom Löter eingeatmet werden, was zur Entwicklung von Berufsasthma, langfristig zu karzinogenen Erkrankungen, Schädigung und Irritation der Atemwege und weiteren ernsten Beschwerden führen kann.

„FumeSafe“, die neue kompakte Einheit zum Absaugen von Dämpfen schützt Arbeiter, indem Lötdämpfe von der Lötspitze von bis zu 15 Löteisen abgesaugt werden, ohne dass die Spitze abgekühlt wird. Der FumeSafe ist ein Präzisionswerkzeug aus rostfreiem Stahl und verfügt über ein leistungsstarkes Gebläse mit wählbarer Spannungsversorgung (230 V bis 120 V) und automatischer Erkennung, sodass er nicht nur in Europa sondern auf der ganzen Welt verwendet werden kann.

Zur Entfernung schädlicher Gase aus Dämpfen des Lötflussmittels werden ein aktivierter Kohlenstofffilter und ein submikronischer HEPA-Filter verwendet, wodurch 99,997% aller Partikel bis zu 0,3 Mikron entfernt, bevor die gefilterte Luft wieder an den Arbeitsplatz abgegeben wird. Die wichtigsten Funktionen von FumeSafe sind die Geschwindigkeitskontrolle, geringe Anschaffungs- und laufenden Kosten, eine einfache Installation, ein Alarm und eine LED-Leuchte für die Meldung von Filterblockaden und leicht auszutauschende Vorfilter, um eine lange Lebensdauer des Filters zu gewährleisten.

Lötdämpfe von einem Löteisen ohne Absaugen	Lötdämpfe von einem Löteisen mit Absaugen

Dass die Maschine geräuscharm arbeitet und leicht zu verlagern ist, sind weitere Vorteile. Die Maschine wird auch mit drei Lötsets und Rohren geliefert.

Mehr Information über den neuen FumeSafe erhalten Sie hier oder kontaktieren Sie uns unter 01709 763000 oder per E-Mail purex@purex.co.uk

Soldering processes such as hand, reflow and wave soldering all produce hazardous fumes that can be harmful if the operator inhales them. Solder fume can cause occupational asthma so it is vital that these fumes are dealt with.

Purex systems utilise 3-stage filtration technology to filter the air from soldering processes before returning cleaned air to the workplace. This avoids the need for expensive ductwork or holes in roofs and walls. Purex units can also be easily moved should the production layout change.

On show at Productronica will be:

• High volume systems for machine soldering
• New solutions for tip extraction
• Patented filter technology
• Digital control systems

Visit us at stand 128 in hall A4 for a chance to win an iPod!

Free Tickets

If you would like a free ticket to the show, normally €47, then please mail us at purex@purex.co.uk

Freikarten für die Productronica

Purex International Ltd, führender Hersteller von Hochleistungssystemen zur Rauchabsaugung, wird seine neuesten Produkte von 15. zum 18.November 2011 auf der Productronica-Messe in München ausstellen.

Lötprozesse wie Handlöten, Reflow-Löten oder Wellenlöten erzeugen alle gefährliche Dämpfe, die dem Bediener beim Einatmen schaden können. Lötdämpfe können Berufsasthma verursachen; es ist also wichtig, dieses Problem zu lösen.

Die Purex-Systeme benutzen eine dreistufige Filtrationstechnik, um die Luft bei Lötprozessen zu filtern, bevor die gereinigte Luft an den Arbeitsplatz zurückgeführt wird. Dadurch sind keine teuren Luftführungsanlagen oder Löcher in Dächern und Wänden mehr nötig. Die Purex-Einheiten lassen sich auch leicht verlegen, wenn sich das Fertigungslayout ändert.

Auf der Productronica werden gezeigt:

• Hochleistungssysteme für das Maschinenlöten
• Neue Lösungen für das Absaugen an der Lötspitze
• Patentierte Filtertechnik
• Digitale Kontrollsysteme

Besuchen Sie uns an Stand 128 in Halle A4 und Sie können einen iPod gewinnen!

Freikarten

Wenn Sie gerne Freikarten für die Messe hätten (Normalpreis 47 €), dann senden Sie uns eine E-Mail an purex@purex.co.uk

Purex is a household name that has been producing fume extraction equipment for many years, and offers an extensive range from individual soldering iron extraction to volume systems capable of absorbing the fumes from wave soldering machines and reflow ovens.

Paul Blundell, Managing Director of Blundell said, “We have been very impressed with the quality of the Purex equipment. The price is comparable to the competition but the standard of build and the extra features that Purex build in to their systems will give their kit the edge and we are sure customers will appreciate the superior design and performance over other systems. We are proud to represent Purex the market leading fume extraction brand”

David Quinn, Regional Sales Manager for Purex comments, “We are delighted to welcome Blundell to our family of distributors and to celebrate the event we have tailored a special single arm unit called the FumeCube-Lite which is packed with features and is offered at a special launch price from Blundells.”

For more details contact Blundell’s on 02476 210270 or visit http://www.blundell.co.uk

Giving Customers What They Want

Purex International Ltd. of Rotherham, manufacture and sell high performance fume extraction systems for soldering, printing and laser applications. Purex carried out a survey of their customers to find out their views on the subject of LEV Testing, virtually all customers responded by saying they would prefer that Purex carry out this important service for them. In response to this demand Purex created and further expanded its LEV testing and support department and recruited the help of a new mascot, THE SENTINEL!

Above: Some of the Purex LEV Testing & Support Team alongside the Sentinel, protecting your LEV system!
The Sentinel mascot represents the Purex mission "Protecting People & the Environment with Innovative Technology"

Jon Young, Sales & Marketing Manager for Purex said, "The response to our customer survey has been excellent, all of our customers were very pleased that we can now supply, LEV test and support their machines with our new Sentinel Pack.

Substandard 3rd Party Filters Causing Problems

During the survey Purex also found that a major concern for many customers was that some 3rd party companies, who may have carried out LEV testing for our customers in the past, have used substandard filters instead of authentic Purex ones. The survey highlighted several cases where substandard, non-Purex filters had been used, the results of this had caused problems for customers such as short filter life, reduced extraction and costly downtime.

By using Purex to carry out LEV testing, customers can be guaranteed that only genuine high performance Purex filters & parts will be fitted to their machines.

Download a Brochure or Request a Test

To request a quick free LEV Testing quote Click Here or download the brochure below.

Download a Brochure

Applications such as soldering, gluing, chemical handling and many others produce dust and fumes. These fumes (if inhaled) can be hazardous to health and can cause illnesses such as occupational asthma, rhinitis, headaches and nausea.

Regulations such as COSHH, NIOSH, OSHA and others around the world stipulate that it is the responsibility of the employer to ensure that workers are protected from hazardous substances such as solder fume, laser smoke, chemical vapour and many others.

To protect workers from hazardous fumes and to help ensure the employer complies with health & safety regulations, Purex have released the enhanced FumeCube Fume Extraction System. The Purex FumeCube is a compact, quiet and portable fume extraction system that can be connected to either one or two flexible extraction arms. The arms can be attached to a bench using clamp brackets and the integrated airflow valve supplied.

The FumeCube is precision made from stainless steel and features a powerful blower to draw contaminated fumes away from the workers breathing zone; the fumes are then passed through a 3-stage filter system which removes contaminants and returns filtered air to the workplace.

The FumeCube is now one of the most fully featured, compact fume extractors on the market with features such as fully automatic flow control and quick change filters plus remote ON/OFF and machine interfacing options.

To download a brochure click here , call 01709 763000 or contact your local distributor.

The FumeCube is now one of the most fully featured, compact fume extractors on the market with features such as remote ON/OFF and machine interfacing options.

New Features

Remote ON/OFF switch (optional)
Now you can easily switch your FumeCube on or off from up to 5m away. This is particulary useful if your fume extractor is tucked away under a bench or in a cupboard where it cannot easily be accessed. This feature is also useful if the work you do is not continuous e.g. intermittent hand soldering as you will be saving energy by turning the FumeCube off between use.

Machine Interfacing Link (optional)
This cable allows you to connect your FumeCube to another machine, for example a small laser. Then, when the laser starts the FumeCube switches on and when the laser stops the Fumecube switches off automatically. The FumeCube can also signal your interfaced machine if the filter alarm is triggered.

What’s in the Box?

With each FumeCube you receive:

• A one or two arm, easy to fit connection kit with;
  • Flexible stainless steel extraction arms
  • Airflow ON/OFF valves
  • And bench brackets and connection hoses.
• Interchangeable pen nib AND conical cowls for use if you need pin point extraction or to extract over a wider area.
• Not just one but FOUR prefilters
• And a long life “HEPA Chemical” or “Chemical only” main filter.

What else do you get?

The FumeCube is now one of, if not THE most fully featured, compact fume extractors on the market. Features include:

• Automatic electronic flow control - maintains a constant extraction rate even as the filter blocks
• Operator adjustable airflow control
• VariColour filter blocked warning system
• Low capital and running costs
• Quick change pre-filters deliver longer filter life
• Submicronic (HEPA) filtration removes 99.997% of  particles down to 0.3 microns
• Activated carbon filtration removes harmful gas
• Simple to install and quiet in operation
• Easy to relocate
• Precision made from stainless steel

To download a brochure click here , call 01709 763000 or contact your local distributor.

Press Images:

userfiles/image/news/fumecube.jpg

userfiles/image/news/dual-fumecube-scene.jpg

Purex International is offering the 1500i Digital Fume Extractor as an ideal solution for larger, professional laser engravers.

The 1500i allows owners to operate their laser in previously ‘off limits’ locations such as schools, malls, offices, exhibition booths and other areas where pumping laser fumes outside the building is not practical, is not allowed or is too expensive to install.

The 1500i filters both dust and fumes from the laser and returns cleaned air to the room and also has innovative safety features such as gas and particle alarms, flow controlled extraction and a graphic display.

For more information visit www.purex.co.uk

  L’estrattore di fumi Purex adatto per le lavorazioni laser

La gamma di estrattori fumi della Purex International Ltd. comprende la versione Digital 1500i, riconosciuta come la migliore soluzione per i professionisti delle lavorazioni laser.

Il Digital 1500i consente di operare in luoghi che in precedenza erano considerati off limits come scuole, centri commerciali, uffici, stand fieristici ed in altre aree dove predisporre aspiratori centralizzati non è pratico, non consentito o semplicemente troppo costoso.

Il 1500i filtra sia polveri che fumi laser e restituisce in ambiente aria pulita in tutta sicurezza, includendo anche funzioni di controllo ed allarmi in caso di presenza di gas o eccesso di particolato.  Il flusso di aspirazione è controllato ed il tutto viene visualizzato tramite un display grafico semplice ed intuitivo.

http://www.marcaturaindustriale.com

Purex International Ltd, manufacturer of fume extraction systems for the printing, laser and electronics industries has set up a team of people to research and promote green policies within the company with the aim of reducing waste, reducing energy usage and increasing recycling rates.

A team of five people volunteered to meet regularly to discuss, implement and promote as many green projects within the company as possible. Leanne Kilcommons – Green Team Leader explains, “When you first start with a project like this you think you will come up with five or six things to change in the company but once you start thinking green, lots of ideas pop up out of the woodwork.”

“Some of the more obvious things to do are recycle metals, glass, cans, plastics, paper, cardboard, fax/copier and printer cartridges, but what about recycling things like stamps? These can be cut out and donated to charities which can use them to raise funds”

“We also looked at ways to reduce the amount of materials we used such as paper. We did this by doing simple things such as not printing customer orders received by email and only printing one invoice for the customer with Purex only keeping electronic copies. Now all orders are now confirmed by e-mail wherever possible to reduce printing and faxing. We also scan all paperwork to generate an electronic version for use between departments.”

It is vitally important that all employees are on board, otherwise many of the ideas from the Green Team would not work.

Some more ideas the team came up with at Purex include:
• Use cups and glasses instead of disposable polystyrene cups.
• Install water displacement devices in all toilet cisterns to save water.
• Cycle rack installed in car park to encourage employees to cycle to work.
• Recycling old computer equipment.
• Making a charitable donation rather than buy Christmas cards.
• Projectors used in meetings for document sharing rather than printing a copy each.
• Reusing paperclips rather than staples.
• Waste paper re-used prior to shredding to reduce new paper use
• Wooden pallets are recycled along with scrap metal.
• Lighting (tubes) now collected when used for recycling.
• Multiple kettles replaced by an efficient water boiler.
• Paper crumpling machine now used instead of plastic packaging.
• Water temperature reduced on hot taps and auto off taps installed to reduce energy usage.
• Recycle station added to shop floor for mixed recyclate (including plastic bottles, yoghurt cartons and glass etc.)

Getting all of the companies employees interested and involved is crucial to success as Leanne explains, “It is vitally important that all employees are on board, otherwise many of the ideas from the Green Team would not work. For example, if only three or four people in the company remember to recycle and the other fifty do not, then the overall impact of the initiative will be minor.

Purex Green Team - Andy Easy, Leanne Kilcommons, Sam Mawhood, Chris Wray, Tony Atkin

“Fortunately, everyone at Purex has grasped the concept with both hands and the results have been amazing. Everyone has put green messages on their emails to remind other colleagues every time they receive an email not to print it off, we have put notices on light switches and electrical equipment to ‘turn off when not in use’, and we even now ask delivery and collection vans to turn engines off when in our car park.”

The recycling theme has also spread beyond the company as members of staff who do not have local recycling collections at their homes can bring in their plastics, cans, etc. and put them in the Purex recycling skips.

Setting up a green initiative is a relatively simple process but it does require people to give some time and effort to achieve results. Not only have Purex found that they can increase recycling rates and charity donations but they have also reduced consumable costs across the company and reduced energy usage so the net result is a cost saving.

Leanne sums up her thoughts, “What surprised me was how easy lots of these changes have been to make. All of our team members have been very supportive and have come up with their own ideas such as removing personal waste baskets to make sure everyone recycles as much as possible. I would think most companies can carry out this exercise and if it results in cost savings then that is even better for the environment and the bottom line.”

For more information please visit http://www.purex.co.uk

Although most printing businesses would rather invest money in inks, media, and new printing equipment to generate revenue, we must not forget that it is the printing professionals who expertly operate the equipment everyday who really make the difference.

A comfortable and safe work environment can go a long way towards maintaining good working relations and promoting higher productivity within the production facility. The printing industry relies on printing professionals to deliver the highest quality product consistently and often to tight schedules. They must therefore be focused, enthusiastic, healthy and energetic to deliver their best consistently, day in and day out.

A major concern among these professionals is air quality. With the many types of inks available today, from solvent inks, mild solvent inks to UV curable inks and variations in between, it is important to know that virtually all of them can degrade the quality of air in the work environment.

Some people may feel and experience the following issues when exposed to a work environment with poor air quality:
• Fatigue and lethargy
• Irritated eyes, throat, and skin
• Headaches
• Nausea
• Distractions due to complaints launched by staff or neighboring businesses.

It is common sense to believe that all of the issues listed above can reduce productivity. In some cases, absenteeism can grind a business to a halt when the key operator does not feel well enough or motivated enough to come to work.

The notion that poor air quality affects productivity is supported by many studies, the most significant of which were those administered by a building controls company (Honeywell Technologies). The survey found that approximately one in five of the 600 worker respondents often or sometimes had difficulty doing their work because of office air quality.  According to Woods (1989),"we could increase the productivity of 20% of our work force" simply by improving the air quality of most offices.

Another study by Evans and Jacobs (1981) states that even the perception that air pollution exists can create stress among employees who believe that it poses threat to their health. In addition to affecting workers' health and productivity, contaminants in building air can harm workers' morale (LaBar 1992). The stress may be particularly intense among people who believe they have no control over the pollution.

 “Solution to the Pollution”

Purex, (working closely with major printer manufacturers), has developed a range of fume extraction systems called Captivair™, which have been designed specifically to improve air quality in wide-format printing applications without the need to pump VOCs (Volatile Organic Compounds) into the environment via an external exhaust. 

Captivair™ MINI	Captivair MAX™

The heart of the Captivair system consists of a filter system loaded with high efficiency chemical adsorbents to capture and lock in the VOCs from the contaminated air. It also has a unique feature that will alert the user when the filter is actually saturated and no longer effective. This takes all the guess-work out of filter replacement schedules which can mean that filters are either changed far too early (wasted money) or far too late (fumes pollute the room).

More good news for the environment is that the Captivair system is designed to be energy efficient, only drawing approximately 200 watts in comparison to other systems, which can draw more than five times more energy to do the same job.

Purex believes that it is important to protect our environment, inside and out, through better design and technology. Each Captivair system is tailored to a specific make and model of printer. All hoses and fittings are included in the system to connect the extractor directly to the printer’s key polluting exhaust points.

Capture the fumes at the source.

Captivair significantly improves air quality in the production environment by efficiently removing VOCs generated by the printing process. Filtered air is re-circulated back into the room, creating a much more pleasant work environment, conducive to higher productivity.

Losses in productivity due to air quality issues caused by the printing process can be rectified or avoided by simply implementing specialized fume extraction solutions such as Captivair. It is a worthwhile and responsible action that will benefit the business and the people who make it possible.

For more information please contact Purex International Ltd on 01709 763000 or visit purex.co.uk.

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Evans, G.W. and Jacobs, S.V. (1981). Air pollution and human behavior. Journal of Social Issues, vol 37, no. 1, pp. 95-125. Honeywell Techanalysis. (1985). Indoor air quality: A national survey of office worker attitudes. Minneapolis, MN.
LaBar, G. (1992). Why employees are sick of Indoor air, Occupational Hazards, August, pp. 32-36.
Woods, J. E. (1989), Cost Avoidance and Productivity in Owning and Operating Buildings. In: Cone, J. E. and Hodgson, M. J., eds., Occupational Medicine, State of the Art Reviews, vol. 4, no, 4, October-December. Problem Buildings: Building-Associated Illness and the Sick Building Syndrome. Hanley & Belfus Philadelphia, pp.753-770.

 

Over recent months many of our customers have requested that Purex offer an installation, LEV certification and support service so I am very pleased to be able to tell you that we have expanded our service department in the UK and we can now offer you the following:

UK LEV testing and servicing

• Extended Sales Support
• Machine Installation, Training and Commissioning
• LEV Testing, Certification & Servicing
• Breakdown Support
• New web based support section on our website

Your Support Team

For our OEM partners, Distributors and End Users, I have listed the people to contact below should you have a specific requirement. All of them can be reached on +44 (0)1709 763000.

• UK Sales - Sally Hadfield & Andrea Smelt
• UK Service - Sam Mawhood
• Overseas Enquiries - Leanne Kilcommons
• Applications Support - Eric Butcher
• Technical/Breakdown Support - Nick Scarr

I am also pleased to tell you about the expansion of our technical support team.

• Simon Collins - is the Engineering Manager heading up the team.
• He is supported by Nick Scarr, Electrical Engineering
• George Lindley Mechanical and Quality Engineering
• and Luke Pass, our apprentice in this field

We have also set up 24 hour emergency phone support on +44 (0)7775 661 806

Overseas Customers

Overseas customers will continue to be supported by their local distributor.

I hope you welcome these positive changes and please do contact us if you have any requirements.

Kindest regards,

Jon Young
Marketing Manager
Purex International Ltd

Laser marking and coding of plastics is a minefield, filled with hazardous and corrosive particles and fume. PUREX International, manufacturers of Purex systems, explain how to get through it.

The use of lasers in the packaging industry, predominantly to code products with use by dates and batch codes is growing. The laser burns away a layer of material in order to produce a mark. The length and depth of the mark determines how much dust and fume is released into the atmosphere. At first glance this may not seem to be a problem, but in a plant coding millions of products per week, the volume of dust and fume generated is considerable.

The importance of an effective fume extraction and purification system is often underestimated. Many engineers understand that extraction is necessary from a health and safety point of view, as laser marking, welding and cutting, produce hazardous dust and fume that cause long-term illnesses like cancer and occupational asthma. The production benefits brought about by using a quality fume extraction system are invaluable in a production environment.

Of particular interest is the new LASEREX range of machines from Purex, which have been specifically designed to combat the harsh conditions caused by marking or coding plastics. For example, PVC and PET release both particles and fumes when marked with a laser. The particles are sticky and can block normal filters within minutes. The fumes released are toxic, and include Hydrogen Chloride and Benzene. HCl fumes are a particular problem as they combine with moisture in the air to form Hydrochloric Acid that attacks and corrodes machinery. These particular plastics are used in a wide variety of products from wrappers and bottles to tablet blister packs.

The LASEREX systems employ a multi-stage filtration system to combat hazardous materials and to increase filter life. Air is drawn in from the process using specifically designed extraction nozzles to prevent particles and fume building up around the laser head and the product. Particle build up can deflect the laser beam, resulting in blurred or distorted marks and therefore increased reject rates. Cool particles can come into contact with the laser, potentially cracking the lens, which would obviously incur replacement costs and lengthy production downtime. Another problem (particularly in the food and pharmaceutical industries) is that particles generated by marking can settle onto the product, again leading to increased reject rates.

A recent Purex installation at a bottling plant in France has seen production rates triple overnight. Phil Mullins, MD of PUREX International explains, "This particular customer was marking soft drink bottles at the rate of 20,000 per hour. The line could potentially operate at 70,000 per hour, but due to insufficient extraction, the product throughput had to be limited as the debris build up at high speeds was causing the mark to blur and become unreadable. We surveyed the process and installed a Purex system that allowed the company to run at full production, with obvious results in the lines profitability."

Once contaminated air is drawn from the process into a Purex machine, it is passed through a patented "concertina prefilter". The life of a filter is directly proportional to the area of filter media it contains, therefore the unique design of the concertina offers around 10 times the life of a normal filter. If you consider that (due to health and safety legislation) the production line has to be stopped in order to change a filter, the resultant savings in terms of downtime are tremendous.

In the case of PVC marking, Hydrochloric Acid has been proven to corrode packaging machinery, rendering it inoperable. Purex systems prevent this happening in a unique way. The acid is removed from the atmosphere and condenses inside the prefilter to form a liquid that is absorbed safely in a specially positioned chemical pad. The Purex machine itself is manufactured from chemically resistant materials to prevent corrosion.

Once through the pre-filter the contaminated air is passed through a main filter. This HEPA/Chemical filter removes the remaining particles and gases, allowing purified air to be returned to the workplace. In this way heating and air conditioning costs are reduced and factory emission regulations are avoided, as air is not vented outside the factory. Purex machines use a microprocessor controlled flow control system that slowly increases power to the pump as a filter becomes blocked. This maintains a uniform flow rate and the pump is not always running at 100%, wasting electricity. With the recent moves to curb power usage, i.e. the climate change levy, this feature is particularly beneficial.

Phil comments, "The main reason for fume extraction is to protect personnel and equipment from hazardous particles and fume. Our products do that, but also offer much more in terms of production benefits. These machines are the result of years of research and trials with our laser customers, who came to us seeking solutions to particular problems."

"Purex machines offer the longest period between filter changes on the market and unlike vent to atmosphere systems, Purex machines are portable so they can be moved with a production line if required. Every factory manager wants increased and problem free production, without unnecessary downtime and rejects. Unfortunately, buying other, low quality fume extraction can prove costly in the long term, so we offer free site surveys and demonstrations to allow our customers to see the benefits of Purex systems."

Purex International will be launching their new Laserex-Alpha™ fume extraction system at the Laser 2003 exhibition in Munich in June.

The Laser 2003 - World of Photonics exhibition is held at Messe München from the 23-26th of June 2003. Laser 2003 is staged in several halls with Purex exhibiting in hall B2 - Production Engineering on stand number B2.679. On show will be several units including:-

• Laserex 1500i - for heavy duty laser applications
• Laserex 400i - for general laser processing
• Laserex-Alpha - economic solution for laser applications
• Fume-Cube - for light usage

The Laserex-Alpha is an economic unit which is designed to purify hazardous fumes that are generated during the laser processing of a variety of materials such as paper, card, glass and plastics. It incorporates a patented concertina pre-filter which can last up to 10 times longer than a standard pad filter. This means that the downtime required to change filters and the cost of filters is greatly reduced.

The main HEPA/Chemical filter removes the remaining particles and gas from the airstream and a powerful high pressure pump is employed in the Alpha which can overcome resistance in the filter (as it becomes blocked) for much longer to further extend filter life.

For heavier laser processes such as etching, cutting, and fast marking lines the Laserex 400i and 1500i units will also be on show.

The dangers that rosin-based fluxes pose to the health and safety of employees who are working in soldering applications have been well documented. The combination of solder and flux produce a complex fume (colophony) that can cause serious medical conditions such as occupational asthma.

Fume extraction equipment for hand soldering, wave soldering machines and reflow ovens is often seen as a necessary capital expenditure on health and safety grounds. What is not always considered is that a good fume extraction system can actually increase uptime and reduce reject rates.

Good fume extraction equipment can prevent the build up of contaminants within, for example, a reflow oven. These contaminants reduce the efficiency of the oven, can be deposited on the boards and worse still, force production to cease while the oven is cleaned. When you consider the cost of shutting a reflow oven down for half a shift or more to clean it (potentially 1000's €), the relatively low cost of a quality fume extraction system to prevent this becomes very appealing.

Another common practice in PCB production is to link the oven to an external venting system, yet this practice has its own problems. Atmospheric conditions can create drafts in the system that can make the temperature profile of the oven unstable; the result being, increased rejects and higher rework costs. To avoid this an extraction system that purifies process air and recirculates it back into the workplace should be used along with a closed loop flow control system to maintain the correct extraction rate throughout the life of the filter.

The Purex Powerflow™ fume extraction system incorporates a whole host of features that actively increase uptime. For example, a unique and patented concertina pre-filter is available that can last 10 times longer than a normal pre-filter which, not only means that consumable costs for the unit are low but also that the line can operate for much longer between filter changes.

OBSOLETE

Purex International has incorporated a unique vacuum control capability in its Purex Powerflow fume extraction systems. By automatically keeping air flow constant, accurate temperature profiles can be maintained in reflow ovens and wave soldering machines. The risk of thermal shock is therefore minimised, which improves product quality and reduces reject rates.

Using conventional fume extraction systems, the air flow will vary as filters fill up with solder particles through their life and become partially blocked. With the Purex system, Purex International's microprocessor-controlled IPCP (Intelligent Purification Control Program) monitors the vacuum in the system and automatically varies the pump's motor speed to keep a constant vacuum. The air flow rate is therefore kept constant, to within a variance of less than 1% throughout the filter life.

Due to the cooling effect of the extraction air flow, conventional extraction systems require frequent and time-consuming manual adjustments to the heating elements of the reflow oven or wave solder machine. These adjustments, with the resultant potential for operator error, are necessary to maintain the required temperature profile. The Purex system avoids this problem completely, with automatic control taking the place of operator modifications.

With a new, unblocked filter, the IPCP's motor control capability allows the motor to be run at a lower speed. This saves power, leading to lower running costs, and extended motor life. The flexibility of the IPCP also means that the motor can be driven at higher speeds when required, enabling higher pressure extraction to overcome the increased resistance as a filter blocks.

The Purex system also solves the problem of fume build-up in the reflow oven caused by extraction speeds dropping. The fume build-up leaves debris on the products, the heating elements and the inside surface of the oven. This debris makes the oven less efficient, and leads to higher product reject rates. It also requires maintenance to remove it, leading to down-time and lost production.

The IPCP allows the Purex extraction system to be easily linked to the reflow oven control system via an industry-standard RS423 interface. The Purex system can then automatically switch off the oven if extraction is insufficient, and the oven can automatically switch on the Purex system at start-up. An optional feature is the Intelligent Purification Network (IPN) which allows remote diagnostics and adjustment of a group of extraction systems from an office PC.

For further information please call Purex International on 00 44 (0)1709 763000.

At the beginning of the 21st Century, subjects such as craft, technology and science play a valuable and important role in our schools and colleges. The hazards created by such activities as soldering, welding, wood and metal working, and chemical experiments cannot be overlooked. The fumes and dust created by these processes are extremely toxic. For example, solder fume can contain the following harmful substances:

• Lead Oxide
• Aliphatic Aldehydes
• Carbon Monoxide
• Hydrochloric Acid
• VOCs (Volatile Organic Compounds)
• Isocyanates
• Abietic Acid
• Isopropyl Alcohol
• Pimaric Acid

Young engineers, children and teachers (who will be exposed to fumes over longer periods of time) can develop many serious medical complaints such as sionasal cancer, bronchitis and especially asthma, a condition already prevalent in children.

It is for this reason that Caerphilly County Borough Council carried out a survey of its comprehensive schools to assess the hazards found therein. To help them perform this task, the council employed the talents of PUREX International, specialists in fume extraction and the manufacturers of the Purex range of extraction and purification equipment. Mike Workman, Principal Commercial & Trading Standards Officer for Caerphilly says "If there is specialist advice available regarding such important matters, it is incumbent on local authorities to make the best use of it"

The outcome of the survey was the fitting of Purex Extraction machines in the CDT Departments of various schools in the region, including St Cenydds, St Martins and Pontllanfraith Comprehensive schools. David Eynon, the Headteacher at St Cenydds asserts "Everyone is entitled to expect safe working practices, and that includes children. It is the responsibility of schools and colleges to educate students in ways of working safely".

The Purex systems are of robust design and operate on several different levels to ensure the working environment is protected. As soon as air is drawn into a Purex machine, its direction of flow is diverted through 90 degrees. This throws larger particles out of the air stream and into a collection tray, thus preventing them from entering the filter and prematurely reducing its life span. Relatively inexpensive pre-filters are used to collect larger particles over 2 microns and prevent them from prematurely blocking the HEPA filters.

The filters used in Purex machines have been designed to offer many unique features: -

• Maximum airflow - Used in conjunction with high-pressure pumps the maximum possible airflow is achieved, which extends filter life.
• Guaranteed unburstable - By employing a unique reinforcing membrane that is 100x stronger than the filter media itself.
• Pleat design - This unique design gives around twice the filter media area than in other filters, thus extending life span.
• Pre-tested - All filters are tested and certified with serial numbers and unique holograms.
• Maximum filtration - In independent tests, these filters remove 99.997% of all particles above 0.3 microns and 95% down to 0.01 micron.
• Precise and rigid construction - Ensures that no fumes are allowed to pass around the filter and escape into the workplace.

The equipment was installed with the minimum of disruption to the schools involved, and is small enough to fit under benches or desks. Pupils can easily plug in and out of the system by means of On/Off Taps and there is a minimum of day-to-day maintenance required, as filters can be changed in seconds. Full annual service and certification to the COSHH Regulations is available from PUREX International along with a 24 hour response guarantee for maintenance calls.

Phil Mullins - Managing Director of PUREX International comments, "Our company has invested heavily in research and development of these systems for schools. They are manufactured using the highest quality materials and very stringent production and testing procedures as we are, at the end of the day, protecting future generations from developing serious medical conditions."

PUREX International has produced useful free information datasheets for local authorities and schools. A video is also available which demonstrates the hazards due to fumes, explains the legal obligations of schools and colleges, and discusses the best solutions to these problems. Useful literature from the Health and Safety Executive (HSE) can also be obtained.

Laser Generated Airborne Contaminants (LGACs) is a term used for dust and smoke, which is generated when a material is processed with a laser. Jon Young - Marketing Manager for Purex International, manufacturers of purification equipment explains why and how LGACS should be dealt with…

Lasers are increasingly used to mark, etch, cut and weld a wide variety of materials. They offer an alternative to traditional machining methods and coupled with the right fume extraction system, deliver excellent results in terms of precision, machining time, flexibility and performance. To comply with COSHH regulations, fume extraction is required for most laser operations in order to protect personnel and to enhance the performance of the laser system itself. It is therefore of paramount importance that the correct fume extraction system is specified.

What happens when laser processing?
When a laser beam is applied to the surface of a material, several conditions can occur:
1. High temperatures that are generated cause the air near to the contact point to expand, generally back in the direction of the lens.
2. The laser beam causes incineration, vaporisation, melting and softening of the material depending upon the distance from the contact point. Rapidly expanding gases pick up and carry the removable particles and droplets at relatively high velocities away from the product material. (fig.1)

3. The contaminants released consist of a wide variety of gases, in some cases noxious i.e. benzene, phosgene. They also consist of the products of complete and partial combustion, including possible oxides of the base material. Stainless steel, for example, releases Chromium and Nickel, which can cause chronic toxicological effects such as liver/kidney disease and cancer.

Production problems caused by LGACs
During laser processing, gases, vapours and particulate matter are released as airborne contaminants, which in most cases, can be classified as harmful if inhaled. Airborne particles also cause problems for the laser if they are allowed to be deposited on the lens, or remain in the processing area, causing beam attenuation and therefore reject rates to increase (fig.2)

Deposition of particulates within the laser enclosure can result in contamination of the product and also the need for regular cleaning of associated operating equipment. The only practical method of overcoming the above problems is to remove these airborne contaminants as quickly and completely as possible by the provision of a fume extraction and purification system.

The range of materials that are processed with lasers is wide and varied so any purification system must be flexible enough to cope with different volumes and types of contaminants.

Purification system design
Airflow rates of between 80 and 5000 m3/hr will ensure the correct level of extraction from most laser processes. The correct rate required depends on many interacting factors and should therefore only be specified by experienced professionals to prevent the provision of an inadequate extraction system. The position and design of the extraction nozzle or enclosure is also a prime consideration if effective extraction is to be achieved, oval or round nozzles should generally be used in preference to thin, slot varieties.

One of the major cost benefits of using lasers instead of conventional methods to process materials is that there are few or no consumables such as drills, milling cutters, saws, etc. Therefore it is important that any purification system does not nullify this benefit by incurring excessive filter costs upon the user.

One method of prolonging the life of a main filter is to use a pre-filter to remove larger particles (=1µm) from the air stream before they enter the main filter. These are supplied in different forms, ranging from pads to bags to a patented concertina design that, as filter life is proportional to the area of media employed, offers around 10 times the life of a normal pre-filter. Pre-filters are made from a variety of filter media and it is vitally important that the correct type is specified by the supplier, otherwise the life of the main filter will be significantly reduced. This is especially true if the material that is processed releases oily or sticky particles.

Many purification systems work on the outdated principle of "top down" filtration, which has been proven not to offer the best filter life and may cause filters to split. A filter for laser processes generally contains HEPA (High Efficiency Particle Arrestor) media to filter out harmful particles (99.997% at =0.3µm and 95% at =0.01µm) plus a chemical layer to filter gases. In low pressure, "top down" purification systems, the contaminated air enters the machine at the top and takes the least line of resistance, at a high velocity through the filter (fig.3). This means that only part of the HEPA and chemical filter media is used and that the air is allowed to pass through the media at much more than the most effective dwell time. Both of these factors reduce filter life and therefore increase consumable costs for the user. Particles can also collect in the pleats of the HEPA media due to gravity and can cause it to split (especially when the particles are moist), releasing hazardous material into the workplace, without the operator's knowledge.

The solution to the aforementioned problems is found in the "Reverse Airflow Principle". This causes the contaminated air to slow and turn through 90 degrees when entering the purification machine. This action causes larger particles to drop out of the air-stream, thus preventing premature filter blockage (fig.4) and particles can no longer collect in and cause the pleats of HEPA media to split because the air is travelling upwards. Air equalisation plates containing holes with a cross sectional area which, correspond mathematically with that of the pump air inlet, should also be used. These, in conjunction with the reverse airflow system, cause the air to slow to the speed at which the filter media is most effective and ensure that the full area of filter media is used. They also increase the rigidity and security of the filters themselves. Some materials release corrosive vapour when processed with a laser, for example, PVC produces Hydrochloric Acid vapour, which coalesces inside the purification machine. In "top down" systems, the liquid HCl can travel through the filters and collect on the electrical wiring and the motor below, causing corrosion and a possible fire risk. Reverse airflow systems on the other hand, allow the acid to drip onto an absorbent pad where it can be safely dealt with (fig.4)

Another method of greatly increasing filter life is to utilise high-pressure pumps that are able to overcome the resistance in a filter as it becomes blocked, for far longer than a low-pressure system is able. The high pressures that are generated necessitate the use of reinforcing that should be employed between the pleats of HEPA media to prevent them from splitting.

Health and Safety
A pressure monitor should be employed to alert the user when a filter is nearly full, this allows them to schedule the purchase of filters, ensuring that extraction from the process is continuous. However, the pressure sensor does not alert the user if:
1. A filter is ruptured
2. There is no filter fitted
3. A seal is broken
4. A filter is damaged
5. The chemical layer that filters out noxious gases is exhausted

Although the use of reinforcing guarantees that filters do not split and a pressure sensor indicates when a filter is full, it is vitally important that the exhaust of any purification system that re-circulates air to the workplace is constantly monitored. It is very concerning that many commercially available laser fume purification systems rely on the operators nose to tell if a filter is blocked or there is a problem with the system. Automatic gas sensors should be used to identify if a chemical filter is exhausted and particle sensors should be employed to ensure that the operator is alerted, if for example a filter has not been fitted or it is damaged and is allowing hazardous particles to pass through it. If these monitoring systems are not in place, conformity with the COSHH regulations will be prejudiced and the users are at risk of potentially developing serious medical complaints through exposure to harmful substances. Such purification systems should also be annually certified by the installer and be well maintained to ensure compliance with the COSHH regulations.

Helping the environment
Perhaps the first thought of many is to vent contaminated air from a laser process out to atmosphere. This method of extraction is not environmentally friendly and there are stringent regulations which govern what and how much can be released into the atmosphere. These regulations can carry large financial penalties should the limits be exceeded.

Apart from regulations, it costs money to either heat or cool a factory. Therefore the venting of air that has in effect been paid for, into the atmosphere is not economical.

External venting does not usually offer precise control of airflow rates. Two common problems with this method are that if the airflow rate is two high, then small components can be sucked into the pipe-work and if the airflow rate is too low, then particles and fume will escape into the workplace.

In a modern production environment, it is necessary to have flexible production lines that can be moved as the factory grows or the production emphasis is altered. Vent to atmosphere extraction requires extensive, fixed pipe-work that cannot easily be moved. If moved, this pipe-work can harbour contaminants that must be cleaned up and made safe. Also, planning permission is often required to cut holes in the factory roof or walls and these holes must be sealed again if the pipe-work moves! This lengthy, expensive process interrupts valuable production time.

A re-circulating system avoids any regulations that govern external emissions. Purified air is returned to the workplace in virtually the same conditioned state/temperature, as when the air entered the machine, therefore air conditioning costs do not rise. Vacuum levels can be set and altered easily for each individual process and most systems can be easily moved, should the process move. Altogether a re-circulating system is much more cost effective, flexible and environmentally friendly than an external system.

Closed loop flow control
A good purification system should employ a closed loop flow control system to automatically adjust motor speed to provide several desirable outcomes. When a new filter is fitted into a purification machine there is little resistance to the air flowing through it, therefore a lower motor speed is required. As a filter becomes blocked, a higher speed is required to pull adequate air through the filter until the filter becomes "blinded" or full.

A fixed motor speed system fails on several counts because the motor will always run at 100%, so the extraction rate cannot be adjusted to the optimum level. If the motor speed is fixed then the extraction would either:
1. Be correct when the filter is new, but as the filter becomes blocked it would fall uncontrollably.
2. Or be far to high while the filter is new (which leads to reduced filter life), then slow as the filter becomes full.

A closed loop flow control system automatically adjusts the motor speed as a filter becomes full, so that the extraction rate remains constant with a variance of less than 1% throughout the life of the filter. The climate change levy introduced recently has seen energy costs rise for manufacturers, so another benefit of flow control is that energy usage is kept to a minimum, which is a most welcome feature.

Laser marking and coding of plastics is a minefield, filled with hazardous and corrosive particles and fume. PUREX International, manufacturers of Purex systems, explain how to get through it.

The use of lasers in the packaging industry, predominantly to code products with use by dates and batch codes is growing. The laser burns away a layer of material in order to produce a mark. The length and depth of the mark determines how much dust and fume is released into the atmosphere. At first glance this may not seem to be a problem, but in a plant coding millions of products per week, the volume of dust and fume generated is considerable.

The importance of an effective fume extraction and purification system is often underestimated. Many engineers understand that extraction is necessary from a health and safety point of view, as laser marking, welding and cutting, produce hazardous dust and fume that cause long-term illnesses like cancer and occupational asthma. The production benefits brought about by using a quality fume extraction system are invaluable in a production environment.

Of particular interest is the new LASEREX range of machines from Purex, which have been specifically designed to combat the harsh conditions caused by marking or coding plastics. For example, PVC and PET release both particles and fumes when marked with a laser. The particles are sticky and can block normal filters within minutes. The fumes released are toxic, and include Hydrogen Chloride and Benzene. HCl fumes are a particular problem as they combine with moisture in the air to form Hydrochloric Acid that attacks and corrodes machinery. These particular plastics are used in a wide variety of products from wrappers and bottles to tablet blister packs.

The LASEREX systems employ a multi-stage filtration system to combat hazardous materials and to increase filter life. Air is drawn in from the process using specifically designed extraction nozzles to prevent particles and fume building up around the laser head and the product. Particle build up can deflect the laser beam, resulting in blurred or distorted marks and therefore increased reject rates. Cool particles can come into contact with the laser, potentially cracking the lens, which would obviously incur replacement costs and lengthy production downtime. Another problem (particularly in the food and pharmaceutical industries) is that particles generated by marking can settle onto the product, again leading to increased reject rates.

A recent Purex installation at a bottling plant in France has seen production rates triple overnight. Phil Mullins, MD of PUREX International explains, "This particular customer was marking soft drink bottles at the rate of 20,000 per hour. The line could potentially operate at 70,000 per hour, but due to insufficient extraction, the product throughput had to be limited as the debris build up at high speeds was causing the mark to blur and become unreadable. We surveyed the process and installed a Purex system that allowed the company to run at full production, with obvious results in the lines profitability."

Once contaminated air is drawn from the process into a Purex machine, it is passed through a patented "concertina prefilter". The life of a filter is directly proportional to the area of filter media it contains, therefore the unique design of the concertina offers around 10 times the life of a normal filter. If you consider that (due to health and safety legislation) the production line has to be stopped in order to change a filter, the resultant savings in terms of downtime are tremendous.

In the case of PVC marking, Hydrochloric Acid has been proven to corrode packaging machinery, rendering it inoperable. Purex systems prevent this happening in a unique way. The acid is removed from the atmosphere and condenses inside the prefilter to form a liquid that is absorbed safely in a specially positioned chemical pad. The Purex machine itself is manufactured from chemically resistant materials to prevent corrosion.

Once through the pre-filter the contaminated air is passed through a main filter. This HEPA/Chemical filter removes the remaining particles and gases, allowing purified air to be returned to the workplace. In this way heating and air conditioning costs are reduced and factory emission regulations are avoided, as air is not vented outside the factory. Purex machines use a microprocessor controlled flow control system that slowly increases power to the pump as a filter becomes blocked. This maintains a uniform flow rate and the pump is not always running at 100%, wasting electricity. With the recent moves to curb power usage, i.e. the climate change levy, this feature is particularly beneficial.

Phil comments, "The main reason for fume extraction is to protect personnel and equipment from hazardous particles and fume. Our products do that, but also offer much more in terms of production benefits. These machines are the result of years of research and trials with our laser customers, who came to us seeking solutions to particular problems."

"Purex machines offer the longest period between filter changes on the market and unlike vent to atmosphere systems, Purex machines are portable so they can be moved with a production line if required. Every factory manager wants increased and problem free production, without unnecessary downtime and rejects. Unfortunately, buying other, low quality fume extraction can prove costly in the long term, so we offer free site surveys and demonstrations to allow our customers to see the benefits of Purex systems."

Introduction
Marking (or coding) lasers are used in a huge variety of applications to add traceable information such as use by dates and batch codes to packaging and products. Examples of these applications are marking bottles in a beverage plant, batch coding of medical devices, marking PCBs and components in the electronics industry, adding data to cables and pipes and many others where permanent information needs to be added to a product. Engraving lasers are commonly used in the gift industry to mark logos and information onto pens, coasters etc. and can also be used to cut shapes in a variety of materials. Due to their increasing affordability and versatility, engraving lasers are also becoming more popular with school and college art and craft departments.

Both laser marking and laser engraving systems burn away layers of material to cut or mark a material. This process generates a fume that contains small toxic particles and gases that are hazardous to health. Some examples are Benzene and Toluene released from certain plastics and Chromium and Nickel given off by some metals. Virtually all materials (when processed) will emit some fumes that are hazardous to health; even cardboard and paper labels can produce respirable dust and formaldehyde.

Worldwide health and safety legislation deems it vital that these fumes are dealt with effectively as they can cause serious long-term medical conditions such as occupational asthma and leave employers open to expensive compensation claims by employees.

The particulate generated by laser processing can also coat or even damage expensive laser optics and cause beam attenuation leading to blurred or incomplete marks. If this dust is not removed efficiently it can also contaminate products that may need to be rejected and it can coat the laser enclosure and associated machinery meaning increased downtime for cleaning. A failure in fume extraction is usually a ‘line stopper’. In high volume production (e.g. PCBs, pharmaceuticals, food/beverage packaging) improperly coded products and the resulting downtime due to fume extraction failure can cost thousands.

Selling or buying a laser.
It is now widely accepted that some form of fume extractor will be required when purchasing a laser. On the one hand the customer has to consider their budget and performance requirements and on the other hand the laser sales person wants to clinch the sale of the laser. There are two ways to go in this situation. (1) The customer can purchase both the laser and a fume extractor from the Laser OEM or (2) they can only purchase the laser and source an extractor from elsewhere. Option (1) is the better method for several reasons.

The laser sales person may think that quoting a laser with an extractor will put the customer off because of the additional cost, but this is usually not the case as the customer knows they will have to buy an extractor from somewhere anyway. By not quoting for an extractor the sales person is losing extra potential revenue and the customer may end up with an unsuitable extractor from another source. The unsuitable extractor may then cause problems with the laser process, for example causing the laser to produce blurred marks. This can leave the customer unhappy and potentially wondering if it is the laser that is at fault.

It is much better then to quote a whole package to the customer who can benefit from the laser manufacturer’s knowledge of specifying the correct extractor. The laser OEM also gets the long-term benefit of supplying the customer with replacement filters and the customer gets a problem free laser process. We (Purex) have even seen the quality of the fume extractor be the deciding factor for the customer when comparing two laser brands.

Budgets are of course a consideration for the customer, however, very low cost fume extractors available on the market can trade performance, filter life and even safety for cost. Simple fans which vent to the outside may seem an economical solution at first but they have significant drawbacks, i ) holes need to be cut in walls / ceilings. ii ) planning permission may be required. iii ) environmental legislation comes into play iiii ) bulky, fixed pipework is required and iv ) what happens if the laser moves? The fan, holes, pipework, fixings etc need to be reinstalled in the new position and the old ones filled and sealed which will be expensive. Also an external venting point may not be available; for example in a shopping mall or school.

A cheap extractor may also cost much more in terms of replacement filters. Worse still if the extractor is inadequate then the health and safety of the operator will be at risk.

What to consider
What does a budget conscious customer and a laser manufacturer need to both be happy with the laser/extractor package? New lasers coming onto the market are less expensive, more compact and are sold into new areas such as schools, offices and shops. So a good extractor needs to be compact, affordable, quiet, mobile and deliver excellent extraction rates and filter life.

The new Laserex Alpha from Purex has been designed along these key principles. The basic machine offers the customer a very affordable solution and comes in two models, a 200m3/hr and a 400m3/hr version depending on the size of the laser. Both models have a small footprint of only 465mm2 so they take up minimal space in areas where this is a consideration. All units are mounted on lockable castors to make the machines highly mobile so if the laser moves the user can simply push the extractor after it.

To reduce noise levels the machines employ Whisper Stream technology, a unique powerful blower and silencing system that delivers excellent performance, maximum reliability and whisper quiet operation at less than 45dBA – essential in places such as schools or shops. It is also of paramount importance that the health and safety of employees is protected. To ensure this the Alpha features the VariColour warning system. This system constantly monitors the condition of the filters and reports automatically via a single variable colour LED.
• Green shows the filter is clean.
• Amber warns the operator that a replacement filter will be required soon.
• Red (along with an audible alarm) tells the operator when to replace the filter.
Filters

A major benefit of buying a laser is that they have few consumables when compared with other methods of marking such as inkjets. Therefore the last thing the customer wants is to have to buy lots of replacement filters for their fume extraction system. Several design features are employed in the Laserex Alpha to ensure filters have a long lifespan and therefore consumable costs are low for the customer.

The first of these is Reverse Airflow, a system pioneered by Purex in the electronics industry and now used in laser fume extraction. Large particles within laser fume will prematurely block a filter over time. To prevent this the speed of the air is slowed when entering the Alpha machine and the direction is changed from horizontal to vertical forcing larger particles out of the air stream in an action similar to a centrifuge. These particles are deposited in the base of the Labyrinth pre-filter thus prolonging its life.

The Labyrinth pre-filter is used to protect the main HEPA filter from premature blockage. It does this by removing particles from the airstream at ≥1 microns in size. This quick change, patented filter technology is not available from any other manufacturer and is designed to overcome inherent weaknesses in pleated paper and bag filter design. The filter’s unique shape, dust holding capacity and deep graded filter media means that more particles can be captured and therefore the main HEPA filter lasts that much longer.

The small, lightweight and robust construction of this filter means that storage and shipping costs are minimal compared with other larger and heavier pre-filters. Also, problematic materials that produce sticky particles can be handled safely and efficiently.

A reinforced, submicronic HEPA media is used in main filters to remove small hazardous particles from the airstream. Purex filters are proven in independent tests to capture 99.997% of particles at 0.3µm and 95% at 0.01µm in size. A high performance deep chemical layer in the filter then adsorbs toxic gas before clean air is returned to the workplace. All filters are easily accessed from the front of the machine and can be changed in seconds without having to move the machine and without using tools.

These design features ensure that filter changes are kept to a minimum therefore consumable costs for the customer are low. This is an attractive fact for the customer and a good selling point for the laser sales person. In many cases the savings made by reducing rejects and downtime caused by incorrectly specified fume extraction systems would pay many times over for a new Laserex Alpha.

Additional features.

As always the customer may require additional control of a fume extractor or they may not, depending on the individual application. The Laserex Alpha has the option to interface with the laser for better control and also to precisely control airflow and speed, increasing filter life and further reducing cost to the customer.

Upgrade pack-1 – Flow Control.
In their most basic form most fume extractors simply turn on or off without the option to raise or lower their extraction rate. This fixed speed method of operation is not as energy efficient as a variable speed drive and having too high an extraction rate can cause drag marks on the product during engraving.

Filters will last longer if the speed at which the particles pass through the filter media is controlled and maintained so the Alpha upgrade pack-1 includes a speed control system that allows the customer to set the airflow to the optimum level on site (particularly useful for engraving lasers). To prevent the extraction rate falling as the filter becomes blocked this upgrade pack also includes a fully automatic “Closed Loop Flow Control” system. This system maintains the airflow at precisely the level set by the operator by automatically adjusting the motor speed. The cost of the upgrade pack is quickly offset by the extension of filter life and increased control.
Closed Loop Flow Control Ensures:
• Filter life is maximised.
• Consumable costs are lowered.
• No manual intervention is required to maintain extraction rate.
• Personnel are constantly protected.
• Airflow is constant throughout the life of the filter.

Upgrade pack-2 – Laser Interfacing:
Additional safety functions and controls are available by simply interfacing the Laserex Alpha with the laser using upgrade pack-2. Interfacing with the laser provides a closed loop, automatic solution where operator intervention is kept to an absolute minimum.

For added safety, the extraction is automatically started when the laser is switched on. This prevents any damage to the laser optics or any hazardous fume entering the workplace. To ensure that all fumes are removed when the laser is switched off, the Alpha will continue to run for a short period before switching off.

If any alerts are generated by the extraction system then a signal is sent to the laser. This signal can either trigger an alert on the laser and associated alarm systems (e.g. a beacon) or it can shut the laser down.

Summary
Health and Safety legislation and the need to protect the product and laser optics make the need for a fume extraction system undeniable. By producing the Laserex Alpha at the right price, with such a good standard feature set and with affordable upgrade options Purex believe that they have catered for everyone’s requirements. The laser sales person increases their turnover and their customer gets the right solution at the right time and price.

For further information visit http://www.laserfume.com for your local office or call Purex on +44(0)1709 763000.

Purex International will be launching their new Laserex-Alpha™ fume extraction system at the Laser 2003 exhibition in Munich in June.

The Laser 2003 - World of Photonics exhibition is held at Messe München from the 23-26th of June 2003. Laser 2003 is staged in several halls with Purex exhibiting in hall B2 - Production Engineering on stand number B2.679. On show will be several units including:-

• Laserex 1500i - for heavy duty laser applications
• Laserex 400i - for general laser processing
• Laserex-Alpha - economic solution for laser applications
• Fume-Cube - for light usage

The Laserex-Alpha is an economic unit which is designed to purify hazardous fumes that are generated during the laser processing of a variety of materials such as paper, card, glass and plastics. It incorporates a patented concertina pre-filter which can last up to 10 times longer than a standard pad filter. This means that the downtime required to change filters and the cost of filters is greatly reduced.

The main HEPA/Chemical filter removes the remaining particles and gas from the airstream and a powerful high pressure pump is employed in the Alpha which can overcome resistance in the filter (as it becomes blocked) for much longer to further extend filter life.

For heavier laser processes such as etching, cutting, and fast marking lines the Laserex 400i and 1500i units will also be on show.

Practical activities such as soldering, cutting and welding are increasingly common in the classroom, lab and workshop but the hazardous dust and fumes generated are not always considered. Indeed, the hazard may not have been identified. Purex International of Rotherham, South Yorkshire has worked closely with several local authorities to identify sources of potential hazards and develop cost effective solutions to the problem.
Soldering - an example of a hazardous fume

The process of melting solder can produce some, if not all, of the following fumes: -

- Lead oxide
- Carbon Monoxide
- Volatile Organic Compounds (V.O.C's)
- Abietic Acid
- Pimaric Acid
- Aliphatic Aldehydes
- Hydrochloric Acid
- Isocyanates
- Isopropyl Alcohol

These fumes can cause occupational asthma, long term carcinogenic diseases and other serious complaints. The result of these illnesses can be expensive compensation claims, long term sickness and poor employee/student relations.

Purex International has produced useful free information datasheets for local authorities and schools. A video is also available which demonstrates the hazards due to fumes, explains the legal obligations of schools and colleges and discusses the best solutions to these problems. Useful literature from the Health and Safety Executive (HSE) can also be obtained.

A survey carried out by the National Asthma Campaign shows that over 100,000 people are admitted to hospital annually with asthma - half of these are children. The COSHH (Control of Substances Hazardous to Health) regulations place a legal responsibility on employers to ensure that their employees and other persons in the workplace are protected from hazardous substances. This legislation applies to local authority and education establishments just as it applies to industry.

Purex International manufactures the Purex range of fume extraction and purification equipment, which includes a number of products ideally suited for use in the processes described above.

To request a free copy of the information and further information on the video, please phone Graham Mattok on 01709 763022.

Many automated processes and those carried out by hand, produce hazardous particles and fume which can cause serious medical conditions such as sionasal cancer and occupational asthma. Purex International have launched the "Fume-Cube" to combat this problem.

The Fume-Cube is the result of customer requests for a low cost, portable arm extraction and purification system for single users and is used to protect personnel from hazardous particles and fumes which are created during:

- Soldering assembly
- Gluing and chemical treatments
- Laboratory/cleanroom tasks
- Rework and repair

The Fume-Cube comes complete with a fully adjustable stainless steel arm and can be used in two ways. It can sit under a workbench and connect to the arm via a simple clamp bracket and flexible hose, or the arm can be inserted directly into the Fume-Cube, which then sits on the workbench. Either way - if the application moves - the Fume-Cube moves with it.

A choice of high performance filters and accessories is available depending on the application.

PUREX International has recently extended its factory due to continued success in the dust/fume extraction & purification market. The capacity of the factory has been increased by more than 30%, with extra office space also being built for new sales & marketing personnel.

Phil Mullins - Managing Director of the company says, "We have invested heavily in R&D to produce machines specifically for the growing laser marking, etching, cutting and welding industries. Problems of blurred marking and lens damage due to dust and fume can now be greatly reduced. This means that the throughput of the product can be greatly increased, thus reducing the cost of the production cycle." Currently over 3000 PUREX systems have been installed in laser processes worldwide.

Phil continues, "One of our other key markets is electronics. We supply many blue chip multi-nationals with Purex equipment for production and hand soldering applications. Purex patented filter designs provide a longer filter life that obviously reduces expensive downtime on production systems including reflow and wave systems."

Purex systems also protect personnel and the environment by filtering hazardous dust and fume from an application and recycling purified air back to the workplace.

The Purex Factory

Many processes where dust and fume extraction is necessary take place in an environment where electrostatic discharge can cause problems.

The actual process of air passing through an extraction system can create a static charge. This charge can damage sensitive electronic components, resulting in expensive reject rates. In applications where powder or dust is mixed with the airflow, for example in the chemical handling and pharmaceutical industries, a build-up of static electricity can pose a potential explosion hazard.

To combat this, Purex International, in conjunction with customers and research establishments, have developed Purex ESD (Electro static discharge) safe air extraction and purification systems. A material comprising of 30% stainless steel fibres has been used in the patented knuckle joints and air flow valves to create earth continuity in the extraction arms.

Purex systems are used in many applications where ESD can be a potential problem, for example in cleanrooms, laboratories, circuit board production, handling of sensitive components and reworking.

For further information or a free site survey contact Purex International on 01709 763000 or visit www.purexltd.co.uk

The new Climate Change Levy (CCL), introduced this year, has meant that electricity costs have risen sharply. Powerflow machines incorporate a number of features that can dramatically reduce running costs, increase efficiency and may allow companies to claim Enhanced Capital Allowances on equipment.

Conventional "vent to atmosphere" extraction systems waste energy by expelling warm air outside the factory which can also raise issues over environmental emission control. Powerflow systems recycle purified air directly back into the workplace thus saving on heating and air conditioning costs.

Powerflow machines also incorporate an electronic flow control system that utilises a variable speed pump. Power to the pump is only increased when a filter starts to become blocked, in this way the correct airflow is always maintained and electricity consumption is always the lowest possible. All of these features are designed to make PUREX systems energy efficient, increase filter life, reduce downtime/reject rates and improve production.

The unique high pressure filters inside Purex machines ensure that no hazardous material or gases are released into the workplace, thus ensuring the health and safety of personnel and reducing impact on the environment.

Many CEMs are increasingly using lasers during the manufacture of PCBs, for example laser drilling systems. They can also utilise wave and reflow or robotic soldering systems as well as traditional hand soldering stations.

The process of lasing a material produces what is known as a 'laser plume' whilst soldering produces a complex cocktail of hazardous materials called colophony. The laser plume can reduce the efficiency and accuracy of the laser by causing beam attenuation whilst both the plume and colophony contain particles and gases which are hazardous to the health of employees, should they inhale them.

To combat this problem Purex International has developed a range of microprocessor controlled extraction and purification systems which remove the laser plume or colophony from the process area and then filter any hazardous particles and gases before returning clean air to the workplace.

A new brochure is now available which details the Purex units and accessories that are required to safely deal with contaminants. It is available for download directly or by calling a local Purex distributor.

Purex also manufacture units which extract and purify fumes that are generated during gluing applications and chemical treatments. Call 01709 763022 for further details.

Purex International are now offering their dust and fume extraction arms as a new product range that is available from their website.

A large variety of arms, nozzles, cowls and connections are available depending on the application which can include; laser processing, laboratory/cleanroom work, medical procedures, soldering, welding and glue/solvent use.

The website shows full technical details and prices, the range includes 25, 38 and 100mm Flexible Arms, Plenum extraction chambers and Cleancabs but of particular interest are the 54mm Multi-Position Arms, which feature a patented joint design to ensure reliable positioning, time after time.

The joint has been designed to overcome an inherent problem with other Multi-Position Arms, which is that over time their joints lose the tension between each of their halves causing the arm to slip. Consequently the extraction nozzle could: -

• Drop into the path of oncoming product if used for example on a laser marking line
• Knock over bottles of chemicals in a laboratory.
• Damage the product being worked on, for example a PCB in a soldering application.
• Be dangerous if used in a medical procedure.

A spring loaded tensioning bolt enables the operator to tighten the Purex 54mm arm using minimum force, creating a positive lock between serrated inner cams on the inside of the joint. Once set to the correct tension, the position of the arm can be adjusted without unscrewing and re-tightening the bolt. The spring action allows the cams to ride over each other and click back into place as the arm is rotated, relocking the new position automatically.

Most of the arms can be used with an existing extraction system by using a suitable conversion kit or alternatively extraction and purification units are available from the Purex range. For further information visit www.purexltd.co.uk