Section 3 Basic Production Process of Rolling Bearings
Due to the different types, structural types, tolerance levels, technical requirements, materials and batches of rolling bearings, the basic production process is not exactly the same.
1. The processing process of the main parts of various bearings:
1. The processing process of the ferrule: The processing of the inner ring and the outer ring of the bearing is different according to the raw material or the blank form. Among them, the process before turning can be divided into the following three types. The whole processing process is: bar or tube (Some bars need to be forged, annealed, and normalized)----turning----heat treatment----grinding----finishing or polishing----parts final inspection---- Anti-rust----storage----(to be assembled>
2. The processing process of steel balls, the processing of steel balls also varies according to the state of raw materials. Among them, the process before frustrating or polishing can be divided into the following three types, and the process before heat treatment can be divided into the following Two kinds, the whole processing process is: cold stamping of bar or wire (some bars need ring punching and annealing after cold stamping)----frustration, rough grinding, soft grinding or light ball----heat treatment- ---Hard Grinding--Finish Grinding--Finish Grinding or Grinding--Final Inspection Grouping--Rust Prevention, Packaging--Storage <to be assembled>.
3. The processing process of the roller The processing of the roller is different according to the different raw materials. The process before heat treatment can be divided into the following two types. The entire processing process is: bar turning or wire rod ringing after cold heading and soft grinding ----heat treatment----string soft point----coarse grinding outer diameter----rough grinding end face----finish grinding end face----fine grinding outer diameter----finish grinding outer diameter ----final inspection grouping----rust prevention, packaging----storage (to be assembled and assembled).
4. The processing process of the cage The processing process of the cage can be divided into the following two categories according to the design structure and raw materials:
(1) Sheet → cutting → blanking → stamping → shaping and finishing → pickling or shot blasting or string light → final inspection → rust prevention, packaging → storage (to be assembled)
(2) The processing process of the solid cage: The processing of the solid cage varies according to the raw material or the roughness. Before turning, it can be divided into the following four blank types. The whole processing process is: bar, Pipe material, forging, casting----car inner diameter, outer diameter, end face, chamfering----drilling (or drawing, boring)----pickling----final inspection---- Anti-rust, packing----warehousing (to be assembled and assembled).
Second, the assembly process of rolling bearings:
Rolling bearing parts such as inner rings, outer rings, rolling elements and cages, etc., after passing the inspection, enter the assembly workshop for assembly. The process is as follows:
Parts demagnetization, cleaning → inner and outer rolling <groove> size grouping and sorting → fitting → clearance inspection → riveting cage → final inspection → demagnetization, cleaning → rust prevention, packaging → finished product warehouse (packing, shipping >.
Section 4 Characteristics of Rolling Bearings
Compared with sliding bearings, rolling bearings have the following advantages:
1. The friction coefficient of the rolling bearing is smaller than that of the sliding bearing, and the transmission efficiency is high. Generally, the friction coefficient of sliding bearings is 0.08-0.12, while that of rolling bearings is only 0.001-0.005;
2. Rolling bearings have achieved standardization, serialization and generalization, are suitable for mass production and supply, and are very convenient to use and maintain;
3. Rolling bearings are made of bearing steel and undergo heat treatment. Therefore, rolling bearings not only have high mechanical properties and long service life, but also can save expensive non-ferrous metals used in the manufacture of sliding bearings;
4. The internal clearance of the rolling bearing is very small, and the processing precision of each part is high, so the running precision is high. At the same time, the rigidity of the bearing can be increased by preloading. This is very important for precision machinery;
5. Some rolling bearings can bear radial load and axial load at the same time, so the structure of the bearing support can be simplified;
6. Due to the high transmission efficiency and low heat generation of rolling bearings, the consumption of lubricating oil can be reduced, and the lubrication maintenance is relatively easy;
7. Rolling bearings can be easily applied to uranium in any orientation in space.
However, everything is divided into two, and rolling bearings also have certain disadvantages, mainly:
1. The load-bearing capacity of rolling bearings is much smaller than that of sliding bearings of the same volume, so the radial dimension of rolling bearings is large. Therefore, sliding bearings are often used in occasions that bear heavy loads and require small radial dimensions and compact structures (such as internal combustion engine crankshaft bearings);
2. The vibration and noise of rolling bearings are relatively large, especially in the later period of use. Therefore, rolling bearings are not suitable for occasions that require high precision and vibration is not allowed. Generally, sliding bearings are better.
3. Rolling bearings are particularly sensitive to foreign matter such as metal shavings. Once foreign matter enters the bearing, it will generate intermittent large vibration and noise, which will also cause early damage. In addition, rolling bearings are also prone to early damage due to metal inclusions and impurities. Even if early damage does not occur, the life of rolling bearings has a certain limit. In short, the life of rolling bearings is shorter than that of sliding bearings.
However, compared with sliding bearings, rolling bearings have their own advantages and disadvantages, and each occupies certain applicable occasions. Therefore, the two cannot completely replace each other, and each develops in a certain direction and expands its own field. However, due to the outstanding advantages of rolling bearings, there is a tendency for latecomers to prevail. At present, rolling bearings have developed into the main support type of machinery, and their applications are becoming more and more extensive.
