F & Z bearings are wearing parts, bearing damage caused by many reasons. From the use, maintenance and repair of the three aspects to analyze here.
I. reason to use
1.Increase the load immediately after a cold start or high speed. Because the diesel engine cold start, not yet fully into the lubrication oil surface, with regard to high speed or high load operation, resulting in poor lubrication effect, oil temperature, the viscosity decreased, undermining the friction
Forming a surface film, and make it a semi-dry friction or dry friction, causing bearing damage.
2 oil shortage to drive. Shortage in oil supply (oil too) run under the circumstances, F & Z can not be achieved properly lubricate the bearing surface, the surface thus creating friction, leading to bearing damage.
3 In the oil pressure is too low running. Oil pressure is too low, the lubrication system can not achieve normal oil circulation and pressure lubrication. Thus, a sufficient amount of oil can not be reliably supplied to between the bearing and journal, so that between the bearing and the journal without adequate lubrication, so that
Cause bearing damage.
4 Cooling water shortage to drive. Insufficient cooling water cooling effect of variation, causing diesel engine operating temperature is too high, so that oil viscosity decreased, F & Z lubricating film between the bearing and the journal's difficult to form and maintain a bearing lubrication conditions deteriorate, resulting in bearing damage.
5 speeding overloaded. Speeding often overloaded, the diesel engine load is too large for a long time in running condition, leading to brutal burning diesel, diesel cause overheating, oil film between the bearing and the journal easily damaged, so that the bearing occurs
Damage phenomenon. Especially the new machine and overhaul aircraft is prohibited speeding overloaded.
II. Maintenance reasons maintenance aspects
1. Poor quality oil. Failing to use oil, or even inferior counterfeit filling oil, the friction surface can not establish a complete and there is a certain thickness of the film, so that the lubricating effect is reduced, could easily lead to bearing damage.
2 Add or replace the oil is not timely. Canadian oil is not timely, it will produce less than the amount of oil above problems. Diesel oil is constantly in the process of work, the person will be sucked in air dust and diesel engines and their combustion products contaminated with the product wear and dirty,
If not promptly replaced, not just the oil impurities will be randomly entered the oil circulation between F & Z bearing and journal, adhering to the bearing surface grit, increased bearing wear, and may even cause the oil channel, pipe blockage, leading to bearing seizure.
3 Clean or replace the oil filter is not timely. This causes the oil filter resistance is too large or even blocked, so that the oil does not pass through the filter from the bypass valve while using unfiltered oil to lubricate the bearing surface, could easily lead to serious bearing and journal surface
Heavy wear and strain.
III. Maintenance
1F & Z mismatch with the journal bearing clearance. The gap is too large, so that the oil is not easy to maintain; if the gap is too small, the oil is difficult to enter. Causing oil film between the bearing and the journal is difficult to form, causing bearing damage.
2 choice of F & Z bearing non-compliance, poor manufacturing quality.
3 assembly, bearing, bearings, crankshafts and connecting rods and other parts of the surface dirty, will cause bearing damage.
Four strategies to extend bearing life
Visible only in the course of the proper use and reasonable maintenance, repair quality assurance in the maintenance, in order to reduce mechanical accidents, reduce consumption and extend the life of the above F & Z bearing damage cause analysis.