plastic bearing material

PLASTICS

Acetal resin/POM-C


• Excellent corrosion resistance to water, salt water and weak chemicals

• Non magnetic

• Only semi-precision grade is possible

• Temperature range -40°C to +110°C

• Suitable for very low load and low speed only


PEEK


• Excellent corrosion resistance to water, salt water and most chemicals

• Good high temperature performance

• Non magnetic

• Wide temperature range from -70°C to +250°C

• Semi-precision only but greater strength so suitable for higher load and speed than other plastics


Polyethylene (PE)


• Excellent corrosion resistance to water, salt water and many chemicals

• Non magnetic

• Temperature range from -50°C to +110°C

• Suitable for low load and low speed and semi-precision only


PTFE


• Excellent corrosion resistance to water, salt water and most chemicals

• Good high temperature performance

• Non magnetic

• Very wide temperature range from -190°C to +250°C

• Suitable for lower loads and speeds than other plastics and semi-precision only


PVDF


• Excellent corrosion resistance to water, salt water and most chemicals

• Can withstand higher temperatures than acetal and polypropylene

• Non magnetic

• Fairly wide temperature range from -50°C to +150°C

• Suitable for low load and low speed and semi-precision only


Our standard plastic corrosion resistant bearings have acetal resin (POM-C) rings, nylon (PA66) cages and balls made from 316 stainless steel or glass. They are also suitable for food applications. They will however, corrode in the presence of certain chemicals and PA66 cages will absorb water after long exposure causing loss of tensile strength. A number of alternative materials for rings, cages and balls are available such as polypropylene, PTFE, PEEK or PVDF.


All plastic bearings are semi precision and like 316 stainless steel bearings, should not be used for precision applications. Due to the softer material, they are not suitable for anything other than low loads and low speeds although PEEK has better load bearing capabilities. Corrosion resistance varies between the materials with PTFE, PEEK and PVDF giving the best all round chemical resistance.


Care should be taken to choose the correct material when using plastic bearings at elevated temperatures. Acetal bearings should not be used in temperatures of greater than 110°C and polypropylene should only used up to 100°C but other materials have good high temperature resistance, particularly PTFE and PEEK which are both suitable for temperatures of up to 250°C although PTFE has lower load ratings. Generally, plastic bearings are not recommended for vacuum applications. PEEK is the exception with very good outgassing characteristics.