Needle roller bearing surface loss. Analysis of the causes of the abnormal

Bearing move part of the surface material like fish scales fall off, this phenomenon is called fatigue spalling. Move in the process of bearing operation, absorb a certain amount of load, even if is the static load, but for steel ball and raceway, the stress is a cycle of reciprocating, exhaustion of materials will occur to move so that the bearing to life. And there are several different definitions of bearing 'life', one of which is known as the 'service life', it represents a needle roller bearing before damage to the actual life is caused by the wear and tear, damage is not usually tired, but due to abrasion, erosion, sealing damage, etc. Test in the laboratory or in be used actually as it is, however, can be significant to see, the appearance of the work in the same premise the same bearing, real life was very different. The life of the bearing ( Or in the hours of work under a certain speed) , definition: needle bearing, within this life should occur at any bearing ring or move on its initial fatigue damage ( Flake or defect) 。 Most of the bearing smoke bad reason a lot - — Than previously estimated load, the effective sealing, tight fit too small, as a result of bearing clearance, etc. Any of these factors factors there is its special damage forms and will leave a special signs of deterioration. Examine the damage to the bearings in most cases, therefore, can discover the possible causes, generally speaking, a third of the needle roller bearing damage resulting from the fatigue damage, a third of the other resulting from poor lubrication, a third of the other resulting from pollutants into the bearing improper handling or installation. However, the damage pattern is also related to the industry don't. Pulp and paper industry, for example, mostly due to bad lubrication bearing damage or contamination caused by not because of material fatigue. Large metal noise reason 1: abnormal load, countermeasures: correction, the bearing clearance, adjustment and load, fixed shell over the shoulder position. Reason 2: bad installation, countermeasures: machining precision of the axis, a hood, improvement of installation accuracy, installation method. Reason 3: lack of lubricant or doesn't fit, countermeasures: added lubricant, select the appropriate lubricant. Reason 4: rotating parts there is contact, countermeasures: modify the sealing contact part of the curved road. Rules reason 1: noise caused by foreign body rolling surface indentation, rust or scars, countermeasures: change the bearing, cleaning related parts, to improve the sealing device, use a clean lubricant. Reason 2: ( After carburizing steel) Surface deformation, countermeasures: change the bearing, pay attention to their use. Reason 3: the raceway surface stripping, countermeasures: change the needle roller bearing. Random noise reason 1: the clearance is too large, countermeasures: research cooperation and bearing clearance, load changes. Reason 2: foreign invasion, countermeasure: the replacement of bearings, cleaning related parts, to improve the sealing device, the use of clean lubricant. Reason 3: spherical injury, stripping, countermeasures: change the bearing. Abnormal temperature rise reason 1: too much lubricant, countermeasures: reduce the lubricant, right amount used, select a hard grease. Reason 2: lack of lubricant or doesn't fit, countermeasures: added lubricant, select the appropriate lubricant. Reason 3: abnormal load, countermeasures: change to cooperate, the bearing clearance, adjust the preload, modify the shell over the shoulder position. Reason 4: bad installation, countermeasures: improve the machining precision and installation accuracy of shaft and the shell, installation method. Reason 5: cooperate with the creep, seal friction is too large, countermeasures: change the needle roller bearing, research cooperation, modify the shaft and the shell, change the sealing form. Vibration ( Axis of jitter, Reason 1: After carburizing steel) The surface deformation, countermeasures: pay attention to the bearing replacement operation. Reason 2: stripping, countermeasures: change the bearing. Reason 3: bad installation, countermeasures: modify the axis, a hood over the shoulder Angle, pad side of the straight Angle. Reason 4: foreign invasion, countermeasures: change the bearing, cleaning all parts, to improve the sealing device, etc. Lubricant leakage is overmuch, discoloration reason: too much lubricant, foreign invasion, wear powder to produce foreign body, such as countermeasures: use appropriate lubricant, study change select lubricant, the replacement of the needle roller bearing, clean the shell.