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What factors affect running condition

已有 188 次阅读 2012-08-17 10:51 标签: running factors affect

In practical mining production, we often have the problems of quick-wear parts（cone crusher）. It affects equipment performance and production efficiency. It is a regularly work for mining machines maintenance. Should we really want to keep machines good condition, we have to learn daily repair at least.
At first, as we all know, we should protect machine from hitting or damage. Ensure clean of them and cannot make machine contact with chemical things.
Besides, bearing is responsible for the whole operation load. It is important to prolong bearing service life. Good lubrication does much with operation efficiency, as well as bearing use life. Above of all, the pouring lubricating oil must be clean, and sealing is good.
Lubrication is the process, or technique employed to reduce wear of one or both surfaces in close proximity, and moving relative to each another, by interposing a substance called lubricant between the surfaces to carry or to help carry the load (pressure generated) between the opposing surfaces. The interposed lubricant film can be a solid, solid/liquid dispersion, a liquid, a liquid-liquid dispersion gasses exceptionally a gas.
In the most common case the applied load is carried by pressure generated within the fluid due to the frictional viscous resistance to motion of the lubricating fluid between the surfaces.
Fluid film lubrication is the lubrication regime in which through viscous forces the load is fully supported by the lubricant within the space or gap between the parts in motion relative to one another (the lubricated conjunction) and solid–solid contact is avoided.
Hydrostatic lubrication is when an external pressure is applied to the lubricant in the bearing, to maintain the fluid lubricant film where it would otherwise be squeezed out.
Hydrodynamic lubrication is where the motion of the contacting surfaces and the exact design of the bearing are used to pump lubricant around the bearing to maintain the lubricating film. This design of bearing may wear when started, stopped or reversed, as the lubricant film breaks down.
Elastohydrodynamic lubrication: The opposing surfaces are separated, but there occurs some interaction between the raised solid features called asperities, and there is an elastic deformation on the contacting surface enlarging the load-bearing area whereby the viscous resistance of the lubricant becomes capable of supporting the load.
Boundary lubrication (also called boundary film lubrication): The bodies come into closer contact at their asperities; the heat developed by the local pressures causes a condition which is called stick-slip and some asperities break off. At the elevated temperature and pressure conditions chemically reactive constituents of the lubricant react with the contact surface forming a highly resistant tenacious layer, or film on the moving solid surfaces (boundary film) which is capable of supporting the load and major wear or breakdown is avoided. Boundary lubrication is also defined as that regime in which the load is carried by the surface asperities rather than by the lubricant.
Besides, we should reduce the temperature effect to machine. During operation, all the parts are running in their own normal temperature ranges. That is, general cooling water is between 80-90。C, while the temperature range of hydraulic system is 30-60。C. Both the lower and higher temperature can cause components wear and damage, lubricating oil becoming bad, and material performance weak and so on. Therefore, during in use, we should guarantee low speed normal operation at preheated stage, so as to reach the standard temperature for normal operation. In no case should the machine operate overloaded in lower temperature. Similarly, higher temperature operation should also be avoided. Operators should check values on the thermograph. If fault occurs, operator should stop the machine at once, check and solve the problems. As for the uncertain problems, we should not let it go and make impact crusher work with trouble. In daily work, the work condition of cooling system should be checked at times. As for water cooling machines, workers pay attention to adding cooling water. As for wind cooling machines, you had better to clean dust as regular intervals to ensure cooling air duct smooth.
Finally, it is equipment minor repair, medium repair and overhaul. The checking results should be kept records in detail, while not only includes repair and replacement records, but also includes use and daily production records, so that we can analysis and judge jaw crusher machine fault quickly and accurately.