During the linear bearing design, there are many errors, including all steel shafts are the same. Do not use in harsh environments linear bearings, bearing races more closely in contact with the rolling element load capability is strong, do not pay attention to the correct choice of the bearing lubricant, fast running linear motion bearings will shorten the period of the bearing, rolling contact body does not wear out, do not pay attention to surface polishing, use a small bearing system will reduce the height of the shaft axis will appear trench damage, as well as the greater hardness of the bearing material the better the performance and the like. In order to better help designers during linear motion bearings are designed to avoid these errors, this article will analyze one by one the above errors.

First, all the steel shaft are the same.

The most commonly used linear bearings shaft materials are high in carbon. Engineers should check with the vendor to use the carbon content of steel, straightness, curvature, surface finish, hardness and hardened layer depth is appropriate for bearing applications. Impurities in the steel can lead to premature bearing damage, because it might have a greater bearing contact stress. The chemical composition and homogeneity of the material shortage will affect the processing properties of the shaft, in particular, will affect the ability to reduce the roughness or the high points. Usually required to contain the surface area with floor trough, also need sufficient hardness and hardening depth to support the contact stress at high bearing loads, ensure that damage does not occur prematurely below the surface.

Second, linear bearings can not be used in harsh environments.

Please pay special attention when using linear bearings in low or deep-sea environment, the design structure, proper sealing and material selection are crucial factors. One to avoid misunderstanding is to ignore the dramatic changes of temperature (for example, -40 ~ 85 ℃) influence thermal effects cause changes in the size of the bearing assembly of axial and radial clearance. Which may require lubrication and seal with a special blade options, and the selection of coating material and the salt spray test is also not possible to measure the final corrosion resistance of a particular application. For example, the standard salt spray and immersion is not exactly the same. In addition, there are many options to protect the surface, all have their advantages. For the rolling bearing, TDC (thin dense chrome) coating than TDN (thin dense nickel) coating has better wear characteristics, not due to the friction characteristics, but its higher hardness. But better than TDC in a standard salt spray test TDN bearing contact stress in terms of the performance is poor.

Third, the bearing ring and rolling body contact, the stronger the closer the load capacity.

People often mistakenly believe that the stronger load capacity, bearing the better the performance. For the rolling bearing, the ratio of the radius of the groove and the rolling body radius factor is close, but due to the material properties of the stress will have certain limitations, geometric consistency (closeness) is expanded to increase the area of ​​the contact surface, thus, increase the load bearing capacity. However, due to certain restrictive, when the closeness becomes large, bearing performance began to decline, load capacity decreases.