With the progress and development of society, mechanization has been widely used in the production and life. As a mechanical bearing an indispensable part of the scope of its use will be more and more widely, as long as there is a place to be used in rotating bearings.
Bearing in machinery and mainly play a supportive role in reducing friction, so the accuracy of the bearing, so the noise is directly related to the use of machinery and life. But often business people will always encounter some customers that the use of the best bearings or bearings its efficiency is not high, which relates to the bearing sliding bearing on the use and selection. Perhaps someone will say, “bearing with it is the user’s choice, and I just what the user wants to sell me anything.”
But as a qualified sales personnel in addition to their product knowledge but also proficient proficient in the use of composite bearing products, namely, a doctor-type sales, according to the user’s performance ancillary products, conditions of use to select the best supporting bearing. This is currently the world’s major companies popular specialized manufacturing and sales, since this way the implementation of one of the Group also achieved good results.
Because a wide range of many types of bearings, will mainly be used with the selection of the most widely used deep groove ball bearings to make some analysis. We hope to recognize bearing fewer people can deepen their understanding of the bearings
First, the choice of bearing
1, the bearing clearance selection: when purchasing bearings are generally only informed what type, class, rarely have the bearing clearance request, the business must ask the conditions of use of the bearing clearance, which bearing speed, temperature, tolerances are directly related to the bearing clearance selection. Usually 3500 rev / min rotational speed of the motor they use CM clearance, such as high temperature and high motor requires a relatively large clearance. Bearing clearance after assembly because of swollen and bore cylindrical reduced and the reduction, reducing the amount of clearance = interference × 60% (excluding the bearing housing is aluminum). For example, the bearing assembly before clearance is 0.01mm, assembly interference of 0.01mm, the bearing clearance after assembly is 0.004mm. In theory at zero clearance bearing noise and life are to achieve the best state, but in actual operation, taking into account issues such as temperature, bearing clearance after assembly is 0.002mm-0.004mm better.
2, bearing type selection: bearing type is normally provided by the user’s technical staff selected according to the bearings supporting the use of the product and the conditions under load. The main business personnel to understand whether the actual user load bearing selected consistent, if not reach the bearing requirements, the customer should be advised as soon as the election model, but unless special products in the choice of models is generally not a problem.
3, oil selection: fat choices are generally selected based on bearing speed, temperature, the starting torque and noise requirements, etc., requires business people to know much about the performance of various oils.
4, bearing seal type selection: bearing lubrication oil lubrication and can be divided into greased. Oil-lubricated bearings are generally used form of bearings, grease lubricated bearings generally used shields or rubber seals seal. Dust cover for high temperature environment or good parts, seals and sub-contact seal two non-contact seal, contact seal dustproof performance is good but starting torque, non-contact seal starting torque is small, but sealing performance no contact is good.
Second, when the bearing Caution
1, a bearing assembly is: Because bearings are precision products, such as improper assembly is likely to cause damage to the bearing channel, leading to bearing damage. Bearing in the assembly should have a dedicated mold and can not beat, when pressed into the shaft force only a small circle, the circle can only force when pressing circle. Assembly requires the use of pneumatic or hydraulic pressure, when the press-fit to the outer upper and lower mold in a horizontal state, if inclined bearing channel will lead to damage due to power, leaving the bearings guide ring.
2, shaft and bearing housing tolerances choice and control: bearings pressed into the bearing block should be flexible rotation no sense. If significant rotation is not flexible, it means that the shaft size is too large, cut to tolerances. The bearing pressed into the shaft turned by hand after the obvious “imperfections” in a sense, it may be too much tolerance of the shaft or shaft roundness is not good. Therefore, when the control shaft and the bearing chamber good tolerance should control the roundness, many domestic manufacturers only the tolerance control, no control of roundness.
3, paint rust prevention: After paint rust is characterized by multiple sealed-type motor, the motor assembly, sound good, but put in the warehouse for some time, the motor becomes very abnormal sound, remove the bearing severe rusting. Many manufacturers will be considered to be bearing problem, through our continuous propaganda, now the motor plant has been realized mainly insulating paint problems. The main problem is because the insulating paint out of the volatile acidic substance at a certain temperature, humidity formation of corrosive substances, leading to bearing damage bearing channel corrosion. This problem can only be a good choice of insulating paint, and after a period of time after drying ventilation assembly.
4, the assembly to prevent foreign bodies: bearing mounted to the rotor dynamic balance when it is easy to produce iron into the interior when balancing bearings, mounted bearings are therefore best done before balancing. Some manufacturers in order to facilitate assembly, the assembly in the bearing chamber coated with some oil or grease lubrication effect, but often the operator is difficult to control the amount, if oil or grease in the bearing interior accumulates more in the bearing rotates very easy access to the interior along the shaft bearing. Bearing chamber is preferably not coated with oil or grease, such as non-coated non-bearings shall have to control indoor accumulates.
Bearing life with manufacturing, assembly, use all closely related, must make every link in order to make the bearing in the best operating condition, thus extending bearing life.
