1.Damage and damage caused by long idle running time
- The alloy layer on the surface of the bearing bush is extruded, displaced, flanged and flake off.
- Damage reason is: the HOWO engine idle quick turn time is too long, the HOWO engine is below the normal operating temperature, under the condition of spray into the combustion chamber fuel cannot complete combustion, part of the failed to combustion of fuel along the cylinder wall into the crankcase, destroyed the lubricating oil film reduces the lubricating effect, at the same time delayed quick turn speed is low, small oil pump oil, So it causes the bearing surface and shaft slight dry friction, so that the alloy layer of the bearing surface
- The surface is damaged, causing wear and damage to the shaft and bearing bush at the same time. To prevent the occurrence of such problems, it is necessary to idle for no more than 5 minutes after starting the HOWO engine according to the operating rules, and no load operation of the HOWO engine can be less than 850 RPM.
2.Damage and damage caused by shutdown (shutdown) after long working time
- The surface of bearing bush alloy is worn, and the uneven surface alloy is shifted from the middle to the two sides.
- Damage reason is: the HOWO engine work in a larger load for a long time, the internal parts are at the highest working temperature condition, especially the combustion chamber at a high temperature, HOWO engine stops running, cooling system and lubricating system stopped working, scattered not to go out and make the relevant parts heat temperature, make each lubricating oil on the surface of the membrane damage, when start again, The abnormal wear of bearing bush occurred before the oil desert was formed on each lubricating surface. In particular, the sliding bearing damage of the supercharger is more serious. At the same time, too high temperature will cause the deformation of the shaft and destroy the operation accuracy
- Damage to the acceleration HOWO engine. This phenomenon can cause serious damage to the piston, cylinder liner and cylinder liner seal ring. So the HOWO engine is growing
- After a large load of time, the HOWO engine should run at low speed and no load for more than 10 minutes, and then stop after the internal temperature is reduced.
3.After the HOWO engine starts, it directly enters high speed operation and full load operation to damage bearing bush
- The seventh and sixth spindle tiles of the HOWO engine are severely worn, and the other bearing tiles are damaged.
- The reason for the damage is that the HOWO engine is put into high-speed operation and full load operation without no-load heating operation after starting. Because the HOWO engine does not meet the working temperature requirements, the force contact surface and operation gap of each part did not enter the best state, and the lubricating oil with low eye temperature is poor fluidity, each transport
- The heat of the moving surface can not be quickly taken away by lubricating oil and other reasons, will cause damage or damage to the bearing bush. The lower the external temperature is, the more serious the damage is to the bearing bush. To prevent such problems, heating operation must be carried out in accordance with the provisions. After the HOWO engine is started, medium and low speed air operation can be carried out when the HOWO engine water temperature rises to more than 70℃.
4.Bearing bush damage or damage caused by adjustment and operation error
Crankshaft thrust bearing (thrust ring) severely worn or damaged, seventh spindle tile damaged.
The reason for the damage is that the axial clearance of the crankshaft is too large or too small, which will cause the damage of the crankshaft thrust bearing. In the process of use, large axial clearance impact, small axial clearance temperature rise will produce abnormal wear and tear, resulting in the damage of the seventh main shaft tile. To prevent this kind of problem from happening
When the HOWO engine is installed, the axial clearance of the crankshaft must be in the standard range of 0.18~0.35mm.
5. Bearing bush is damaged or damaged due to incorrect installation Some bearing bush unilateral wear serious, tile alloy surface wear.
The damage reason is: the deformation of the connecting rod exceeds the standard allowable range: the solid moment of the bolt of the bearing bush cover is not uniform; One side back of bearing bush was touched during installation
Injury; Bearing bush installation position is not accurate and up and down is not in alignment.
6. One-side wear of seven bearing bush is serious, and the middle bearing is more serious than the two ends
The reason is: bearing hole deformation taper: crankshaft bending (crankshaft bending is caused by uneven operating clearance, vibration caused by serious wear or damage of relevant parts, balance shock absorber failure. Failure of balance shock absorber can also cause crankshaft fracture); When the bearing bush is installed, the positioning part of the position is not aligned or reversed: the upper and lower tile dislocation oil hole is not smooth.
7. Bearing back corrosion or trace mobile wear mark: bearing positioning table damage bearing irregular outside member.
The reason is that: in order to correct the operation clearance, the two sides of the bearing plane is filed, and the elastic contact force between the bearing and the bearing hole is destroyed; The bearing cover is installed in reverse, which changes the contact area and motion clearance between bearing and shaft; The bolts on the bushing cover are not tightened in accordance with the prescribed method and torque. Too large or too small torque and uneven tightening torque of bolts on the same tile cover will cause bearing bush damage.