No Escape From the Labyrinth™

21 February 2013
No Escape From the Labyrinth™

Applications such as hand and machine soldering, laser processing, solvent use and many others all generate hazardous dust and fume that should be controlled by an extraction and filtration system. The cost of ownership of these systems in terms of replacement filters can be a concern for the end user but the patented Labyrinth™ filter from Purex may just be the answer.

Pre-filters made from paper and a variety of bag type filters have been available for decades from a whole host of sources. One of the main disadvantages of these types of filter is that their dust holding capacity (and therefore life) is limited due to their design and the materials they are made from.

To expand on this, the capability of a filter to capture and retain particles depends on the cross sectional area of filter media 'in which' and 'on which' particles can be contained. In the case of paper filters the main disadvantage is that they can only capture dust particles on a single thin face of material and so the filters have to be much larger in order to deliver any kind of economic lifespan.

Because of this, the dimensions of a typical filter of this type can be large, making it a bigger item to store, more expensive to pack and ship and more prone to damage during shipping. They can also be more cumbersome to handle, as removing a big filter of this type can increase the required operating footprint of the machine, causing problems for operators in production environments where space is paramount.

Purex Patented Filter Design

Extensive trials with laser manufacturers and long term research and development work with filter media specialists have resulted in the patented Labyrinth filter that overcomes the disadvantages of current pleated paper and bag filter technology.

The Labyrinth filter is a radical departure from current 'off the shelf' filters and has been specifically designed for filtration of laser fume. Fig-1 shows how a paper filter can only capture particles on a single thin face of media whereas the multi layered Labyrinth filter media is a graduated fiber matrix that delivers a much greater dust holding capacity throughout without affecting airflow.

Purex Labyrinth Filter for Dust


The greater dust holding capacity means that the end user does not have to change the filter as often and therefore laser dowtime is kept to a minimum. Also, because the end user buys fewer filters, the annual cost of replacements is lower. Further savings are made by the customer in shipping costs, as compared to bulky rigid filters which may be expensive to transport, the Labyrinth is small, compact and lightweight and less likely to be damaged in transit. (Fig.2)

Purex Labyrinth Dust Filter is Small and Compact

• Small
• Compact
• Lightweight
• Low transport costs
• Less succeptable to damage
• Easily handled
• Minimises storage space



Electro-Cell technology

Electro-Cell technology locks particles within the filter by actively attracting dust particles to the media fibres. The unique design of the filter pockets also allows multi-directional airflow, further increasing the performance of the filter.
Another positive and important point for the customer is that Purex machines are front loading, so the operator can simply open the door and push the small replacement filter into place in seconds without having to disconnect the machine from the process.

Although small for shipping and storage purposes, the Labyrinth filter delivers massive performance once inside the machine.


Comparison Table

Disadvantage of Paper Pre-Filters

Purex Labyrinth Solution

Some pleated paper filters need to be large and bulky in order to be effective which means that the machine has to be bigger to accomodate the filter. This means a larger operating footprint is required and more working area is needed to change filters

The Labyrinth filter is exceedingly compact which also means the Purex unit has a very small operating footprint
Filter media only captures dust particles on a single thin face. The Labyrinth filter uses multi-layered filter media that captures up to 20 times the quantity of dust particles.
Some pleated paper filters need to be large and bulky which increases shipping and storage costs for customer. The Labyrinth filter can be posted anywhere in the world for a fraction of the cost to the customer.
In some box type bag filters the area of media that is used is limited in order to keep the bag small. This means a short lifespan. The Labyrinth filter employs up to 20 multi-layered sections of filter media to capture particles. This ensures very long life coupled with low cost of ownership.
Filters require regular replacement due to poor filter life. During extensive trials, Labyrinth filters have been proven to have a very long life which means a low cost of ownership.
General 'off the shelf' replacement filters can vary in quality. The Labyrinth filter is specifically designed and evaluated by Purex Engineers and tested by leading laser OEMs
Some extraction units using paper filters load from the back or top, yet have controls at the front. This means the operating footprint of the machine has to be bigger, thus taking up more room in the workplace. In confined production facilities the user may have to disconnect the machine and take it to a more open area to change the filter. This means a loss of time and a loss of valuable space.

The design of the Labyrinth filter saves valuable space, meaning Purex machines have a small footprint. The filters are changed from the front in seconds without disconnecting or moving the machine! 

All controls and filter changes are accessed at the front