Prevention extend the service life of the method of rolling bearing burning diesel engine

Sliding bearing early damage is more common than the rolling bearings burned, so to prevent sliding bearing early damage is very important. The correct maintenance of the sliding bearing is an effective way to reduce early TIMKEN bearing damage, extend the service life of rolling bearing is the reliable guarantee. In motivation, therefore, daily maintenance and repair, must pay attention to the bearing surface of the alloy, the back end and the appearance of edge angles in shape, if there is any abnormal or half signs of wear and tear, to seriously investigate the cause, and take appropriate measures to improve the bearing of the working conditions, pay much attention to the prevention of early damage of the sliding bearing. (1) strictly diesel engine body main bearing hole alignment and roundness measurement. For the body main bearing hole alignment measurements, must be measured by the engine block size more precise alignment, measuring the crankshaft beat at the same time, by selecting the thickness of the bearing shell, make the oil clearance in the shaft to achieve consistently. All that happened in watts, diesel engine speed, and so on and so forth, before the assembly must be tested to the body main bearing hole alignment, ductile iron crankshaft length is not greater than zero. 14 mm, steel crankshaft length is not greater than zero. 12 mm, at the same time for the body bearing hole of the roundness, cylindricity also have requirements. (2) improve the quality of bearing maintenance and assembly, strict control of connecting rod on the percent of pass. Improve the quality of bearing hinge distribution, to ensure smooth and no spots on the back of shaft bearing, positioning bumps intact; Bounce off amount of 0. 5 ~ 1. 5 mm, it can ensure the rear axle assembly tile with its elasticity and bearing hole joint close; All requirements of the new and old connecting rod measuring the parallelism and the degree of distortion, ban on of unqualified connecting rod; In bearing in the upper and lower two pieces of each end bearing shall be higher than that of bearing seat plane 30 ~ 50 mm, higher quantity can ensure torque tighten bearing cap bolts by the regulation after the bearing and the bearing seat close coordination, have enough force of friction self-locking, bearing is not loose, good heat dissipation effect, and prevent bearing ablation and wear; TIMKEN bearing working face can not scrape match method reached 75% ~ 85% contact pattern as a measure, should be not scraping makes fitting clearance of bearing and shaft neck reach requirement improve the performance of cleaning equipment, strict quality management to cleaning, to improve cleanness of the various parts of the diesel engine parts. At the same time, environment purification assembly site, make cylinder liner dust cover, make the diesel engine assembly cleanliness has increased significantly. (3) selection and filling lubricating oil reasonably. In use process want to choose the lubricating oil, the oil film surface tension small, make the formation of the gas bubble breaking when corresponding impact of oil flow is reduced, the bearing can effectively prevent cavitation; Lubricating oil viscosity grades may not arbitrarily add, lest increase bearing coking tendency; Engine oil level of lubricating oil must be within the scope of the standard, lubricating oil and gas recruitment must be clean, prevent the entry of any dirt and water, at the same time ensure that the sealing effect of the various parts of the engine. (4) the correct use and maintenance of the engine. When installing bearings, should be in the movement of shaft and bearing surface coated with grades clean engine oil. After refitted engine bearing, before starting the first should be shut off fuel switch, use the starter machine engine idling several times, when the engine oil pressure gauge, open the fuel to switch, after I have a show and put gas in low speed, start the engine running. Idle running time is not more than 5 min. Be new and overhaul engine break-in period, after the ban surge vastly decrease in load for a long time period and high speeds; End of the engine full load for a long time after work, can't stop immediately, must let the engine to idle after 15 min in a low speed to stop, or internal heat is not to go out. Strictly control the locomotive starting temperature, increase the machine delivery time. Oil iron spectrum analysis on a regular basis, reduce the accident, combined with the oil iron spectrum analysis, early detection abnormal wear, according to the oil pattern of iron spectral analysis, accurate determination of abrasive components and parts may occur, nip in the bud, to avoid grinding burn axis accident. In order to make the rolling bearing parts quenching tempering after large surface residual compressive stress, could pass infiltration during quenching heating carbon or nitriding atmosphere, make the surface carburizing or nitriding for a short period of time. Because the steel quenching when heated austenitic actual carbon content is not high, far lower than on the phase diagram shows the equilibrium concentration, so it can absorb carbon ( Or nitrogen) 。 When austenite contains higher carbon or nitrogen, the Ms is reduced, quenching surface when the martensitic transformation in the aftermath of the inner layer and center, produce the large residual compression stress. GCrl5 steel by carburizing atmosphere and the atmosphere carburizing quenching ( Both low temperature tempering) After treatment, the contact fatigue test, you can see that the surface carburizing of life than carburized increased 1. 5 times. The reason for carburizing of the surface of the parts has a larger residual compressive stress. Affect the service life of high carbon chromium steel rolling rolling bearing parts degree of factors and control of main material is: ( 1) In the original organization in front of the quenching steel requirements small, dispersion carbide. Can use high temperature austenitizing 630 ℃ or 420 ℃ high temperature, also can use forged heat to achieve rapid annealing process. ( 2) For GCr15 steel after quenching, demanding the average carbon content is 0. About 55% of cryptocrystalline martensite, 9% Ar, and about 7% is uniform, round state did not dissolve carbide microstructure. Can use quenching heating temperature and time to control the microstructure. ( 3) Parts after quenching temperature tempering requirements surface has a larger residual compressive stress, which will help to improve the fatigue resistance. Can be used in quenching heating surface carburized or short time nitriding process, make the surface has a larger residual compressive stress. ( 4) Manufacturing steel rolling bearing components, the requirement with high purity, mainly is to reduce the O2, N2, the content of P, oxides and phosphide. Can use esr, vacuum smelting technology measures such as the material 15 PPM or less oxygen is advisable.