The durability of filter plates for filter presses needs to be comprehensively evaluated in combination with specific working conditions (such as corrosiveness, temperature, pressure, hygiene requirements, etc.). Different materials have their own advantages. The following are selection suggestions:

Corrosion resistance

Strong acid/strong alkali environment: Polypropylene (PP) and stainless steel (304/316L) perform well, while cast iron is prone to acid corrosion.

Special media: For hydrofluoric acid, PP or PTFE-lined composite filter plates should be selected. Organic solvents can be selected from stainless steel or special plastics.

2. Stress resistance

High-pressure working conditions: Cast iron and stainless steel have high strength and can withstand higher pressures (such as 20-30 mpa). PP filter plates are typically suitable for medium and low pressure (≤10MPa).

Anti-deformation: Cast iron and stainless steel have strong anti-deformation capabilities, while PP may slightly deform under high temperature or high pressure.

3. High-temperature resistance

High-temperature environment: Cast iron (with a temperature resistance of approximately 200℃) > stainless steel (above 300℃) > modified PP (100-120℃) > ordinary PP (70℃).

Steam filtration: Cast iron or stainless steel is preferred.

4. Wear resistance and fatigue life

Frequent start-stop: Stainless steel and cast iron are more resistant to mechanical fatigue, while PP may age and become brittle after long-term use.

Wear medium: Suspensions containing particles may accelerate the wear of the filter plate grooves. It is necessary to replace the filter cloth regularly or choose thickened PP.

5. Economy

Initial cost: PP < cast iron < stainless steel; Rubber filter plates have a relatively low cost but are applicable in limited scenarios.

Life cycle cost: Although stainless steel and cast iron are expensive, they have a long service life and require less maintenance. PP needs to be replaced frequently according to the working conditions.