Page 18 - dust collection systems

For applications that demand the highest filtration

efficiencies (near ZERO emissions), the filter media may be

laminated with expanded PTFE membrane (e. However, since

expanded PTFE membrane is delicate and can get easily

damaged, care should be taken in filter bags laminated with

expanded PTFE membrane.

Apart from the properties of the fibres themselves,

specifications for filter fabrics should include the ‘weight per

unit area’, which gives an indication of the thickness, and

therefore the strength and durability of the fabric, and an

indication of its permeability.

The permeability of the material depends upon the

construction of the fabric, which depends on whether it is

woven or nonwoven/felted, its thickness, tightness of weave,

and so on. This information allows an estimate of the

pressure drop across a filter to be made.