NSK bearings burned and influence factors of fatigue life

NSK bearing state of burn injury refers to: the bearing raceway wheel, roller and cage in the rotation sharply fever until discoloration, softening, deposition and damaged. The main cause of NSK bearings burned is due to the bad lubrication bearing, may use the informal lubricant, or lubricant too much, too little, is not correct. The second is probably too big load ( Preloading is too big) 。 Speed is too large. Clearance is too small. With water or other foreign matter invasion. If the above two cases are not the shaft, the accuracy of bearing box, shaft deflection. See here, I think everyone wants to know the solution, first of all, to study lubricants and lubrication method, choose the right bearing lubricant, and its dosage, and the selection of the bearing must be corrected. Study to cooperate, bearing clearance, and preloading, and improve the sealing device. Check the shaft and the precision of the bearing housing. NSK bearings is recommended to use, must pay attention to the installation, lubrication, to achieve accurate as far as possible clearance and so on each link, in place. NSK bearings fatigue life general refers to a certain technical condition ( State of structure, process, cooperate, installation, clearance and lubrication condition, etc. ) Rolling bearing, the host running the actual service condition, until the rolling surface when the fatigue and cannot meet the requirements of the host of bearing inner and outer ring ( Shaft, seat) The gross - the number of relative rotation — The total number of turn. When bearing turn a roughly constant or is known, the fatigue life is available and total number of turns the corresponding operation to the total number of hours to represent, in addition, still should be paid attention to: ( 1) And the influencing factors of NSK bearing fatigue life very much, can't all be estimated or through standard test conditions and to eliminate, this causes NSK bearing fatigue life has a great deal of actual discreteness, therefore, the fatigue life of bearing express parameters for rated L10 life, the meaning of the L10 in ISO standard of R281 clearly stipulated as follows: 'a batch of bearing enough on the same amount, the rated life L10 revolution ( Or the number of hours in at constant speed, 90% of this batch of bearing in the fatigue spalling occurring before can reach or exceed the number of revolutions ( Or hours) ”。 So far, all countries in the world to follow the rules. In some countries such as America, still use the concept of value in life. Median life LM refers to a group of NSK bearing the same values in life, namely 50% of NSK bearings before fatigue spalling can reach or exceed the total number of turns, or under a certain speed from time to time, the median life LM not the arithmetic mean of a batch of bearing life. Generally the median life LM is 5 times of the rated life. ( 2) , rated life concept is only applicable to enough of a batch of NSK bearings, NSK bearings and does not apply to the individual. For example article 40 sets of 6204 bearing according to their use is its rated life is 1000 h without fatigue damage occurs, the rest 4 sets may be less than 1000 h would appear fatigue failure of bearing, rated fatigue life is the meaning of this batch of bearings in normal life play its material potential can be expected. So in most cases, the user in selecting the bearing still first as the fatigue life calculation, according to the actual failure categories, such as wear life, take the results in a smaller value for the calculation of bearing life.