(1) Crude Effective Filter
Coarse filter material is generally non-woven fabric, wire mesh, glass, nylon mesh and so on.
(2) Intermediate-effect filter
The commonly used intermediate efficiency filters are: M-I, I I, IV foam plastic filters, YB glass fiber filters, etc.
(3) High efficiency filter
The commonly used high efficiency filters are GB type and GWB type. Its filter material is ultra-fine glass fiber filter paper with very small pore.