Bearing industry abroad, in the '60 s has formed a stable ferrule grinding processing technological process and basic method, namely: the double face grinding, centerless cylindrical plunge grinding, raceway, centerless grinding groove lapping processing.In addition to the special bearing structure, several processes, require additional ring all is according to the process of mass production of processing.For decades, the process is not a fundamental change, but this does not mean that no bearing manufacturing technology development.In a nutshell, only 60 s establishment and development of "double - centerless cylindrical - cut into the ground - super lapping" this technological process, and the corresponding was born into a series of cuts centerless grinder and ultra lapping machine, spare parts and precision of the work 3 ~ 5 um, single processing time 13 ~ 18 s (small and medium size).Is mainly used in the 70 s 60 m/s high speed grinding, control is used in great quantities in the grinding machine grinding technology and control, is characterized by set into a circuit of the electronic control technology of digital control technology is widely used, so as to improve the stability of the grinding machine and process, parts machining accuracy reaches 1 ~ 3 um, 10 ~ 12 s parts processing time.Since the 80 s, the technology and equipment of the machining accuracy is not problem, the main development direction is on the premise of stable quality, the pursuit of higher efficiency, more convenient adjustment and manufacturing system of numerical control and automation.

2. Bearing ring grinding processing

In bearing manufacturing, grinding labor accounts for about 60% of the total labor, the grinding machine used number about 60% of all metal cutting machine tool, grinding the cost of more than 15% of the cost of the bearing.For high precision bearings, grinding of the larger proportion.In addition, is the most complex, the machining process of grinding on the understanding is still the most inadequate.This complexity, displays in: the required performance indicators more and higher accuracy;Processing and forming mechanism of more complex, many factors affecting machining precision;Processing parameters on-line detection difficult.Therefore, for the bearing grinding, one of the key working procedure in the production of how to adopt new technology, new technology, with high precision, high efficiency and low cost to finish grinding process, is the main task of the grinding.

2.1 high speed grinding technology

High speed grinding to achieve two goals of modern manufacturing technology to improve product quality and labor efficiency.Practice proves: if the grinding speed increased from 35 m/s to 50 ~ 60 m/s, the general production efficiency can be increased by 30% ~ 60%, and for the durability of the grinding wheel increased about 0.7 ~ 1 times, workpiece surface roughness parameter value is about 50% lower.

General grinding speed reaches more than 45 m/s is called high speed grinding.Home to me the ZYS developed in the eighty s - eighty automatic bearing internal grinder, take the lead in the domestic bearing industry ferrule grinding processing and application of high speed grinding technology, successfully developed a high rigidity, high speed, high power electric spindle and high speed grinding wheel.And high speed grinding is already widely used at home and abroad, and along with the widespread adoption of high grinding ratio, high durability of superhard abrasive such as CBN, the grinding wheel grinding speed reached 80 ~ 120 m/s, is even higher.Mikrosa such as: Germany, Japan KOYO company centerless grinder, Japan TOYO company bearing internal grinder, surface grinding wheel linear velocity of 120 m/s, the inner surface grinding linear speed of 60 m/s ~ 80 m/s.General grinding speed reaches more than 45 m/s is called high speed grinding.Home to me the ZYS developed in the eighty s - eighty automatic bearing internal grinder, take the lead in the domestic bearing industry ferrule grinding processing and application of high speed grinding technology, successfully developed a high rigidity, high speed, high power electric spindle and high speed grinding wheel.And high speed grinding is already widely used at home and abroad, and along with the widespread adoption of high grinding ratio, high durability of superhard abrasive such as CBN, the grinding wheel grinding speed reached 80 ~ 120 m/s, is even higher.Mikrosa such as: Germany, Japan KOYO company centerless grinder, Japan TOYO company bearing internal grinder, surface grinding wheel linear velocity of 120 m/s, the inner surface grinding linear speed of 60 m/s ~ 80 m/s.

2.2 CBN grinding wheel grinding technology

Cubic boron nitride abrasive CBN abrasive, made by the grinding wheel is called the CBN grinding wheel, the main has the following characteristics: (1) high hardness, high thermal conductivity, good thermal stability, can withstand 1300 ~ 1500 ℃ high temperature.2 high durability, small abrasion, grinding ratio of up to 4000 ~ 4000 (grinding ratio refers to the amount of grinding process to remove the workpiece material and the ratio of the grinding wheel wear) and ordinary corundum grinding wheel is only 50 ~ 80.(3) small grinding force, grinding heat is small, small machining stress, surface stress thin or not.(4) the auxiliary time (dressing grinding wheel, replacement of grinding wheel) greatly reduced. To ring for bearing industry in our country, the use of CBN grinding is a kind of new processing technology, the application prospect is very broad, but need to study to solve the following technologies: CBN grinding wheel manufacturing technology, finishing technology, special bearing grinder, grinding coolant and so on. Due to the CBN grinding wheel has a good processing characteristics, the use of CBN grinding wheel bearing ring grinding abroad has already been developed and used in the production, as the production and processing technology of a revolution.Since 1982, CBN grinding wheel in Japan has a large number of applications, and high-speed growth.

2.3 the surface grinding wheel automatic dynamic balancing technology

For surface grinding, because of its high grinding wheel and body for heterogeneous groups, center of gravity is always deviated from the spindle center wheel system, inevitably caused when the high-speed rotating wheel system and the vibration of the whole machine, directly affects the service life of machine tool.In this case, grinding will be difficult to achieve high precision, easy to cause the workpiece surface grinding marks, corrugated degree increased. Machine tool grinding wheel on the installed directly on the machine or other way of automatic dynamic balancing device, fast directly after boot near the equilibrium position, automatic balance more complete and can also be omitted grinding wheel static balance.This technology breakthrough to promote the development of grinding cutting technology and at the same time can greatly limit extend the service life of diamond grinding wheel, trimmed with and spindle bearings, reducing machine tool vibration, keep the original precision machine tools for a long time.