What are the main reasons that affect the performance o […]
What are the main reasons that affect the performance of self-lubricating bearings?
The performance of self-lubricating bearings is largely affected by the surface roughness and hardness of matching bearing materials. High-quality shaft surfaces can extend bearing life. On the contrary, rough, low-hardness surfaces affect the life of the bearing.
A. Shaft surface roughness
1. When used under fluid lubrication conditions, the matching shaft surface is required to be mirror-finished to minimize the gap of the oil film as close as possible to the fluid lubrication state, thereby improving the performance of the bearing.
2. The bearings are used under dry friction conditions, as long as the surface roughness of the matching shaft is controlled within the range of Ra=0.4-063.
B. The hardness of the shaft
The surface hardness of the shaft is not less than 220HB. Under the condition of high load and rocking motion, the shaft must be heat-treated with hardness above HRC50 or hard chrome plated, and then ground. After surface treatment, it can improve corrosion resistance, improve surface hardness, and improve lubricity. Under similar corrosion conditions in seawater, the matching shaft must be plated with two to three layers of hard chromium. The rough surface of the shaft, sharp burrs, and grooves can damage the sliding layer of the bearing.