08
2022
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12
Tetrafluorocorrosion-resistant O-rings, Teflon O-rings and PTFEO rings produced by tetrafluorotype O-factory have the following advantages.
Author:
How much influence does the corrosion-resistant O-ring process of the bearing chamber and bearing outer ring on the motor housing have on the bearing outer ring? How to ensure its assembly process in small batch and batch production.
1. The size of peristalsis depends on four aspects: the peristaltic torque T1 generated by the rotation of roller rotator; Anti-rotating torque T2 generated by outer ring friction (not considered when clearance); The peristaltic torque T3 produced by centrifugal force and the friction torque T4 produced by O-ring. When T1+T3T2+T4, peristalsis prevention can be achieved. Therefore, it is necessary to calculate the magnitude of anti-peristalsis effect.
2. The size of T1 is proportional to the radial force and the coefficient of rolling friction; T2 is proportional to the radial force, the coefficient of sliding friction of the outer ring and the shell, and the diameter of the outer ring; T3 is proportional to the mass and speed of the roller, and the rolling friction coefficient is proportional to the diameter of the outer ring. T4 is proportional to the cross section excess of the corrosion-resistant O-ring, and the coefficient of sliding friction between the corrosion-resistant O-ring and the outer ring is proportional to the diameter of the outer ring.
Reference value: 0.0013(NSK). Other friction coefficients can be found in mechanical manuals or measured by testing.
3. Factors to consider in the assembly process: low stiffness of corrosion-resistant O-ring. In order to avoid falling off during assembly, the process requires vertical assembly of bearings or shells; In order to avoid O-rings in the assembly process, the ring groove depth of the bearing chamber should exceed the O-ring radius, and the bearing entry part should be increased with large chamfer; In order to facilitate assembly, if the structure allows, it is better to open the ring groove on the bearing.
1. In the bearing fit design: compared with the load, when the tolerance fit is too loose, the fit surface will produce creep, resulting in the rotating parts unable to rotate synchronously and the static parts unable to be relatively static. Peristalsis will further lead to slight corrosion of the bearing, with common friction marks on the surface and a dark brown mating surface.
2. Place the elastic O-ring between the mating surface of the bearing static ring to increase the rotating friction; One or more O-rings can be arranged between mating surfaces as required. Engineering application shows that this method can be used in bearing design, bearing load is small, working temperature is low, design fatigue life is low.
3. In order to prevent creep between surfaces, other countermeasures in the design and manufacturing process, such as: improve shaft stiffness through reasonable heat treatment, insert steel sleeve to improve bearing stiffness, use ring surface coating (such as chrome plated) bearing, increase axial contact area, improve axial support adequacy, improve bearing fit surface shape + roughness, etc.
4. In order to ensure the consistency of assembly, attention should be paid to the processing quality and precision of the groove in the bearing seat hole during the manufacturing process. In order to prevent the axial clearance from being too large when the O-ring is assembled, the contact compression difference between the radial and the bearing outer ring is large.
5. Suitable corrosion-resistant O-ring materials and environmental characteristics should be selected in small batch production and batch production. For example, silicone seals are not resistant to oil. If the silicone O-ring is placed in an oily environment for a long time, it is easy to corrosion and fracture; In the chemical corrosion environment, only the fluorine rubber seal ring has corrosion resistance, in order to avoid the O-ring fracture in the process of use.
6. Engineering application shows that after disassembling and assembling bearings for many times, the O-ring appearance quality and compression performance of the bearing seat with O-ring will be greatly reduced. It is also easy to damage the O-ring in a single assembly process due to the quality of the grooved machining (burr, size deviation).
Tetrafluorocorrosion-resistant O-rings
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Shanghai Lingsheng Seals Co., LTD
Telephone:021-54419691
Phone:13671848590
Fax:021-39650919
Address: No. 611 Yuetai Road, Songjiang District, Shanghai
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Contact us
Shanghai Lingsheng Seals Co., LTD
Telephone:021-54419691
Phone:13671848590
Fax:021-39650919
Address: No. 611 Yuetai Road,
Songjiang District, Shanghai
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