Description

Configuration of slewing bearings Slewing bearings is a kind of large-size bearing with special configuration which can bear axial load, radial load and tilting moment. Generally, a slewing bearing has mounting holes, lubricating holes and sealing system which can meet different needs of different machines under different working conditions. Our slewing bearings include the following types: 4 point contact ball slewing bearing; Double-row angular contact ball slewing bearing; Crossed cylindrical roller slewing bearing; Three-row cylindrical roller slewing bearing; Ball and cylindrical roller combined slewing bearing. These bearings can be divided with no-gear, external gear and internal gear. Slewing bearings can meet different needs of different machines under different loads as per their types. 4 point contact ball slewing bearing can carry higher dynamic loads; Crossed cylindrical roller slewing bearing can carry higher static loads; The preload of crossed tapered roller slewing bearing can make it better support rigidity and higher rotation accuracy; three-row cylindrical roller slewing bearing can carry large load. Packaging and storage Packaging Before delivery, every slewing beairng is filled in rust-preventive lubricant on the inside surface, outerside surface and races, and then packed with plastic film, kraft paper and blue belt; For those slewing bearings with outerside diameter more than **0mm Storage All LDB slewing bearings are made with rust-preventive and oil-seal treatment before delivering form our factory. Under normal storage conditions, we can promise that the bearings will not rust within *2 months from the date when the it is delivered from our factory. For those slewing bearings in stock which are not beyond the above period, if the original packaging is undamaged, they can be stocked for long time. But for those which are beyond the period but still need storage, washing and oil-seal treatment should be done. Slewing bearings should be placed horizontally on the dry, ventilated and flat ground. It should be stored separating from chemicals and corrosives. When many slewing bearings are stacked, at least three equispaced, equal-altitude wooden block should be put in the circumference direction between slewing bearings. The wooden block should be put identically. Maintenance At **0 hours of rotation of LDB slewing beraings after installation, please examine whether the pretightening force of mounting bolts is conforming. Later, re-examine at continuous rotation of **0 hours. After installation of slewing bearings, please fill the lubricating grease. Please rotate the slewing bearing when filling the grease so that the grease can be uniformly distributed. After working for a period, the slewing bearing will inevitably lose part of grease. Please replenish the grease one time every *****0 hours for those working slewing bearings; For those slewing bearing working in formidable with high temperature or much mill dust, the period should be shortenedï&frac*4;› When the machine stops for storing up, please fill in enough lubricating grease. Material It is important to design exactly and choose correctly the materials to assure LDB slewing bearings have the high performance and high reliability. Materials of rings and rolling parts Generally, LDB uses carbon-chromium bearing steel GCr*5SiMn or GCr*5 for rolling parts and surface-haredned steel *0Mn, *2CrMo, 5CrMnMo for the rings. Material of cages The cages for LDB slewing bearings include integral cage, segment cage and spacer-type cage. We use *0# steel or ZL**2 birmasil for integral and segment cages, PA ***0 resin or ZL**2 birmasil or QA********5 albronze for spacer-type cages. In recent years with continuous development of material industry , nylon GRPA*5.*5 started to be applied for segment cages. Material of seals Generally, LDB uses NBR or VITON for seals. But there still very few slewing bearings LDB manufactured in early period sealing with felted wool.