Reasons for damage to diesel engine bearings



There are 7 major reasons for diesel engine bearing damage.

First, there is a lack of lubricant. The reasons include: no new oil is added after the oil is discharged; the crankcase screw plug leaks the oil due to the vibration loss; the filter block is blocked, the return valve spring is invalid, the blisters on the cylinder oil passage or the process hole are clogged off, the bearing bush is seriously worn, and the bearing bush is on the bearing. The oil hole is not aligned with the oil supply hole on the tile seat or the upper and lower tiles are incorrectly installed, the fuel pump plunger is worn and leaking, the injector is poorly atomized, and the diesel oil leaks into the crankcase, etc., so that the lubricating oil is thinned until Lack of oil and "burn" injuries.

Second, the lubricating oil is not clean. Reasons include: oil contains a lot of metal abrasives, dust or mechanical impurities.

Third, the lubricant grade does not meet the requirements of the specification.

The fourth is improper use of maintenance. The reasons include: the overload causes the bearing alloy to break and fall off, indentation on the bearing raceway, and even the inner and outer rings are broken; the axial clearance of the tapered bearing is too large, and the wheel collides when rolling on the rough road, so that the rolling element is pressed outside the bearing. The circle is broken; the calcium-based grease is not added once every 10~12h.

The fifth is the manufacturing defects of the bearing. Reasons include: deformation of the retainer, relative deflection of the inner and outer rings, skew of the rolling elements, and the like.

Sixth is poor preservation. Reasons include: poor rust prevention or exceeding the oil seal period without re-grinding; or rubbing with rust to reduce the accuracy, bumping or falling.

Seven is improperly installed. The reasons include: hammering the ring with a hammer and causing cracks; knocking the bearing with a punch causes the bearing to collapse; the seat is damaged by the shock wave and the other race, and the hard knocker causes the retainer to deform; the two bearing centerline The straightness error is too large, which causes the needle roller, the roller and the inner and outer rings to be subjected to a large pressure, resulting in premature fatigue damage of the bearing; the bearing is biased or forced to cause damage to the inner ring; the bearing is mounted to the outer diameter of the bearing outer ring. In a much smaller hole, the outer ring is deformed or broken, and the bearing rotation is stuck; the inner ring hole of the bearing and the journal or the outer ring of the bearing and the hole are loosely fitted, resulting in shaft deflection, poor gear meshing and damage to the bearing; assembly The error of the ruler chain causes the pre-stress of the bearing to be too large; the crankshaft journal taper is out of tolerance, the bearing bush is out of round, the incorrect press fit and the center line of the connecting rod are out of adjustment, etc., the bearing bush is damaged, the tapered journal and the bearing bush are asked. If the gap at one end is too large, the bearing bush is eccentrically worn, resulting in high temperature and increased wear.
For more information and purchase please visit: https://www.supplyforever.com

Minimum load of rolling bearings



When the load is too small - if the speed is high during operation, it will cause slippage, and if the lubrication is insufficient, the bearing will be damaged. The following are the recommended values for the bearing minimum load:

Ball bearing with cage P / C =0.11

Roller bearing with cage P / C =0.02

Without cage bearing P / C = 0.04

(P is the equivalent dynamic load and C is the basic dynamic load rating)

The minimum load of the thrust bearing can be found in the overview of the bearing size table.

Excessive size reduces the service life of the bearing: the reason is that the oversized bearing is prone to slippage, and the original design is a lubricant for life, and the internal working stress is increased. Slip will cause a glued and reliable working week, which is better than using the bearing capacity. For this reason, as in the calculation of the corrected bearing life, when calculating the bearing life, in addition to the basic rated load, other factors of the bearing must be affected.
For more information and purchase please visit: https://www.supplyforever.com