Writer: Eric Bearing Limited
1. What is TIMKEN bearing chamfer
Chamfering is a term in mechanical engineering. In order to remove the burrs caused by machining on the parts and to facilitate the assembly of the parts, chamfers are generally made at the ends of the parts. The chamfers can be seen everywhere in our lives, on the frame of the mobile phone, on the steel door, on the vase and so on.
The general function of chamfering is to remove burrs and make them beautiful. However, the chamfers specified in the drawings are generally required by the installation process, such as bearing installation guidance, and some arc chamfers (or arc transitions) can also reduce stress concentration and strengthen the shaft The role of the strength of the class parts. In addition, it can also make assembly easy, generally before the end of processing.
On agricultural machinery parts, especially round parts and round holes, the end faces are often processed into a chamfer of about 45°. These chamfers have many functions. They must be checked carefully and fully utilized during maintenance operations. Otherwise, it will bring many difficulties to the maintenance of agricultural machinery and even cause unexpected failures. For example, before the forming process of small parts such as bolts, chamfering is also carried out, so that the material can easily enter the forming mold. TIMKEN 48685/48620 bearings online , pls click here :
2. What is the function of TIMKEN bearing chamfer
(1) TIMKEN bearing steel must be chamfered during rough machining before heat treatment. In this way, when the material is heat treated, stress release, internal structure redistribution, cracks are not easy to appear, and deformation reduction is very important. Chamfering can solve the problem of stress concentration.
(2) Chamfering and deburring make the product not sharp and will not cut the user
(3) It plays a role of guiding and positioning during assembly.
Generally, the outer chamfer of the outer ring and the inner chamfer of the inner ring of TIMKEN bearings are rounded corners. In addition to effectively avoiding contact stress, the most important thing is to facilitate installation. The rounded corners can ensure a good transitional fit.
Especially during the use of TIMKEN bearings, the matching shaft and the positioning surface of the shaft hole, that is, the shaft shoulder and the bearing seat shoulder part, the chamfer size of this part directly affects the correct installation of the bearing.
According to experience, we can know that the chamfer of TIMKEN bearing installed between the axle box and the shaft is larger than the chamfer of the bearing box and the shaft shoulder. The chamfer of the TIMKEN bearing must be larger than this arc to ensure that the bearing fits. Axial positioning surface.
When the chamfer of the TIMKEN bearing is smaller than the chamfer of the bearing housing and the shaft shoulder, it cannot be assembled in place, which is likely to cause a series of problems such as stress concentration at the chamfer of the bearing, inclination of assembly, and inability to match other matching parts.
3. The importance of TIMKEN bearing chamfer and fit
If the interference between the TIMKEN bearing and the shaft is too small, and the inner ring rotates under load, harmful sliding in the circumferential direction will occur between the inner ring and the shaft.
The sliding phenomenon of the ferrule, which is called creep, is a phenomenon in which the bearing point moves in the circumferential direction when the interference of the mating surface is insufficient, and the ferrule moves in the circumferential direction relative to the shaft or the bearing seat.
Creep denier occurs, the mating surface is obviously worn, and the shaft or bearing seat is damaged. Moreover, the abrasion powder will penetrate into the bearing, causing abnormal heating and vibration.
Therefore, generally in the fit of TIMKEN bearings, it is important to give a suitable amount of interference to the ring bearing the load. Fix the ferrule on the shaft or bearing seat to prevent creep during operation. However, only relying on tightening the end face of the bearing in the axial direction is not enough to prevent its creep from occurring. In addition, there are many occasions where there is no interference between the inner and outer rings, depending on the conditions of use and the difficulty of bearing installation and disassembly. In these cases, the mating surface will be damaged by the creep surface, so it is necessary to consider lubrication and other measures.