What factors affect the cold resistance of the sealing kit?
(1) The cold resistance of the sealing kit is determined by important factors such as the characteristics of the lip material, the characteristics of the sealing medium, the shaft eccentricity, and the starting speed. Due to the normal shaft eccentricity, the elongation of the seal kit lip edge reaches a few percent, so NOK uses the lip material TR10 value as the allowable temperature reference in the low temperature range. However, in actual use, for example, even at a temperature lower than the TR10 value, sliding heat may be generated after starting, and the temperature of the lip may increase, which may deteriorate the elasticity of the colloid. On the other hand, even under temperature conditions higher than the TR10 value, the amount of shaft eccentricity may increase, and the lip may not follow the flow, which may cause leakage.
(2) Therefore, it is dangerous to determine the allowable temperature of the sealing kit based on the TR10 value, so many important factors mentioned above need to be considered.
Check steps before installation of seal kit:
1. The seal kit must be kept clean from collection to assembly. Before installing the sealing kit, do not tear the wrapping paper too early to prevent debris from sticking to the surface of the sealing kit and make it work.
2. Make a machining inspection procedure before assembling to check whether the dimensions of each part of the seal kit are consistent with the dimensions of the shaft and cavity. The machining of the shaft end surface and the cavity should be smooth, and the chamfer should be free of damage and burrs. The assembly site must be cleaned. The shaft and seat hole should be machined into an assembly chamfer of 15 to 30 degrees, especially from the inside to the corner, without inclination. It is recommended to round up the assembly location. The shaft installation part must not have burrs, sand, iron filings and other debris to prevent accidental damage to the seal lip. The cavity size must be suitable for the outer diameter and width of the seal kit.
3. Check whether the lip of the seal is damaged, deformed, whether the spring has fallen off, or is rusted, to prevent the seal from being damaged by external forces such as squeezing and impact during transportation.