PTFE membrane is a microporous ‘skin’ applied to various filter medias to provide extremely high filtration efficiencies even when filtering sub-micron particulate.
Its non-stick surface offers the added benefit of excellent dust release on the cleaning cycle under moist operating conditions, or with ‘sticky’ dusts.
About PTFE Filter Media
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene. It is hydrophobic or water repellent. The filtration process with PTFE stretched film is different to other materials such as glass fibre or polyester felt. Glass fibre and polyester felt need to be of a certain thickness to be efficient as they “trap” the dust particles within a maze of tunnels. The filtration with PTFE stretched film is done at the surface because the micropores act as a gatekeeper.
PTFE Membrane Media Applications
Cartridge filters utilizing PTFE membrane media are widely used in the Pharmaceutical, Food and Chemical Industries, in Process Filtration and Pneumatic Conveying applications. PTFE coated media excels at capturing fine particulate materials well under 1 micron in size. In fact, it is so effective that it can provide filtration efficiencies of very near 100% in some applications.
The Problem of Premature Pleat Collapse
Unfortunately, this high-efficiency particulate collection comes at a price. Due to the PTFE coating, the air permeability of membrane medias is generally in the area of 65-80% lower than that of conventional polyester filter media. In pleated filters, this causes higher pressures on the outside of the pleats and can lead to a further restriction in the air flow due to pleats collapsing against themselves, leaving no channel in which the filtered air can pass. This can cause premature blinding or failure of the filter cartridge and possibly the equipment it supports, incurring unnecessary downtime and expense.
Prevent Pleat Collapse with Fab-Tex Tandem Pleat Technology
For this reason, Fab-Tex has created a unique solution to solve the problem of pleat collapse in high-pressure applications. Tandem Pleat filter construction adds a double layer of plastic mesh media between each pleat to provide pleat support across 100% of the surface area. This allows for utilization of all the filter media, leaving no “dead spots” to restrict air flow.
Price of Combining PTFE Media with Tandem Pleat Technology
Although effective, PTFE membrane media are expensive, 5 to 10 times that of conventional filter media.
Combining PTFE media with Tandem Pleat Technology, as compared to using a cartridge with unsupported PTFE media alone, will ensure:
- Maximum value possible is achieved from each filter cartridge.
- Increased lifespan and overall performance of the filter.
Over the long run, this may make up for the initial higher price tag by having to conduct filter change-outs far less often. Talk to Fab-Tex to see if PTFE membrane combined with Tandem Pleat Technology may be an effective long term solution for your equipment.