Selecting and using a combination of INA bearings simple detection method

The thesis& oil drops after stir in white paper ( It's best to filter paper) , form the oil stain, staining outward from the center after about 2 ~ 3 hours of gradually spread, form three concentric rings. According to the color of the three regions, size and shape can identify the state of the oil. From the lower shell oil with a little oil, besmear is on the fingers, fingers and thumb twist mill. If you have any impurity or feel oil like water without a sticky feeling, even send acerbity or have a sour taste, oil has been bad. If twist after grinding on the finger to see small shiny metal grinding, the serious wear and tear parts, engine are also shows that the oil must be replaced immediately. 1, bearing type selection, bearing type is commonly used by the user's technical personnel according to the product of form a complete set of conditions and the load bearing for selection. Business people mainly learn the user's actual load is consistent with the selected bearing, if combination bearings can not meet the use requirements, should suggest customer re-election model as soon as possible, but unless special products on the choice models generally do not have what problem. 2, the selection of the bearing clearance: user when buying bearings generally just let us know in what type, grade, rarely on the clearance request, business people must ask bearing conditions of use, the combination of bearing speed, temperature, tolerance is directly related to the selection of the bearing clearance. Generally under 3500 RPM speed motor mostly adopts CM clearance, such as high temperature and high speed motor, require the use of relatively large clearance. Bearing clearance after assembly will rise because of the inner hole and cylindrical reduction and lead to reduce, the reduction of clearance = interference quantity x 60% ( Except the bearing chamber is aluminum) 。 Such as bearing clearance is zero before assembly. 01 mm, interference when assembling the quantity to zero. 01 mm, bearing assembly after the clearance of 0. 004mm。 In theory at zero clearance noise and bearing life can reach the best state, but in actual operation considering the problems such as temperature, bearing clearance to 0 after assembly. 002mm- 0. 004 mm is better. 3, the choice of grease: selection is usually based on combination of oil bearing rotating speed, heat resistance, noise requirements and choose starting torque, etc, require business personnel to the performance of a variety of oils and fats to be understood. 4, the choice of bearing seal type: the bearing lubrication can be divided into oil and grease. Grease lubrication oil lubrication bearing is generally choose bearing, bearing dust cover is generally selected or rubber seal seal. Dust cover suitable for high temperature or the use of good parts, seal two points contact seal and non-contact seal and contact seal dustproof performance is good but the starting torque, the sealing type starting torque is small, but there is no contact sealing performance is good. Bearing assembly surface and cooperate with the surface of the parts, if there is any collision, rust layer, abrasive dust, sand, dust and dirt, a bearing installation difficulties, cause assembly position is not correct; Second, these attachments form abrasive, easily galling combination bearing working surface, affect the assembly quality. Therefore, before the installation, should axis neck, the surface of the bearing shell hole, shoulder end face, and connecting parts, such as liner, washer, with the end cover and so on the surface, a careful inspection. If there is any rust layer, usable fine file file, fine cloth, at the same time also want to clear the attachments on the surface of bearing assembly and connection parts.