Introduction and application of POM PE PA PEEK PI PTFE bearings

1. Classification of plastic bearings

A.Plastic rolling bearings

B.Plastic Plain Bearing

Plastic rolling bearings work when the friction is rolling friction, and plastic plain bearings work when the sliding friction; rolling friction of the size of the main depends on the manufacturing accuracy; and plastic plain bearings friction of the size of the main depends on the bearing sliding surface of the material.

Plastic plain bearings generally have self-lubricating function on the working surface; Plastic plain bearings are generally made of engineering plastics with better performance; As plastic plain bearings have many advantages over metal type plain bearings. Plastic bearings are also used in a continuous extension of the occasion, from fitness equipment to office equipment and the automotive industry and so on are used in plastic bearings. At present, there is no automobile traveling on the highway that does not use plastic bearings, plastic plain bearings have replaced metal bearings and plastic rolling bearings.

2. Materials of plastic bearings

A. POM plastic bearings, PA plastic bearings

POM and PA materials have good mechanical strength and wear resistance, suitable for making more precise plastic bearings, working temperature from -60 ℃ to 100 ℃, high surface strength and smooth, basically no tension, its good self-lubricating properties and low coefficient of friction, in keeping with the traditional advantages of plastic bearings on the basis of the application of precision and higher speed operation. Among them, POM plastic bearings are one of the most widely used of all plastic bearings, generally the inner and outer ball material is POM or PA, and the cage is glass fiber reinforced Pa66 (GRPA66-25). The balls are glass, stainless steel or ceramic balls, which perform well in alkaline environment but are not suitable for running in acidic corrosive environment.

Characteristics:

(1) High rigidity, high hardness, high impact strength even at low temperatures;

(2) Excellent elasticity, good creep resistance;

(3) High thermal stability and very good dimensional stability;

(4) Good sliding properties, wear resistance;

(5) Physiologically inert, suitable for food contact.

B. hdpe, PP, UPE materials

It has been proved that it can be used in relatively weak acid and alkali cross environment (30% Cucl2 solution and 30% NaoH solution test OK), so it is suitable for most of the acid/alkali/salt/solvent/oil/gas and seawater corrosive environment. With general plastic bearings of oil-free self-lubricating, anti-magnetic and electrical insulation properties, but the mechanical strength is low, easy to deform, so such anti-acid and alkali plastic bearings are not suitable for larger loads and higher speeds, in order to overcome the shortcomings of such anti-acid and alkali plastic bearings. In contrast, the use of UPE material has better strength, low friction characteristics and low-temperature applications (as low as -150 ℃), the general inner and outer ring material using HDPE, PP or UPE, cage material using HDPE, PP or UPE, ball for the glass ball, stainless steel ball or ceramic ball. In this way, the comprehensive performance of acid and alkali resistant bearings will be greatly improved.

Characteristics:

(1) good corrosion resistance, in a certain temperature and concentration range can be resistant to a variety of corrosive media and organic media

(2) high mechanical strength, cut in liquid nitrogen temperature (-196 ℃) to maintain high toughness

(3) good self-lubrication, high wear resistance

(4) strong anti-adhesion ability

(5) very low water absorption, excellent electrical insulation properties

(6) Good resistance to high energy radiation

C. PTFE, PI high temperature and corrosion resistant plastic bearings

PTFE and PI as an emerging engineering plastics materials, is proved to be all known engineering plastics in mechanical strength dimensional stability and high temperature performance is better, of which the PTFE long-term use of temperature up to 260 ℃, PI long-term use of the temperature is as high as 300 ℃, and its excellent corrosion resistance, in the medium strength of acid and alkali corrosive environments can still run freely, it is generally used in the production of the need for outer ring PTFE or PI material selection, ball is generally Zro2 or Si3N4 ceramic ball. The disadvantage of the bearings for precision operation in a more severe environment is that the material itself is more expensive, so the cost is higher.

3. Application of bearings

(1)Automotive industry - low weight, improve fuel efficiency and reduce CO2 emissions.

(2)Commercial equipment, electromechanical, fitness equipment, furniture and decorative building materials.

Due to the non-magnetic nature of thermoplastics, application areas such as bank card readers and document scanners or medical equipment, and also MRI scanners and X-ray machines.

(3)Food and poultry processing industries.

(4)Underwater applications - plastic bearings can be developed with different levels of inertia while achieving low torque of 0.041Nmm, utilizing the low water absorption and self-cleaning features of plastic bearings used in the manufacture of hydrotherapy machines, pool cleaners and dishwashers.

HONY Plastic specializes in high performance plastics and engineering Plastics Injection Molding and CNC machining plastic bushing and bearing .