How to repair the driving shaft and bushing of the oil pump of Weichai generator set after wear?

Due to the weight of the driving gear of the oil pump itself and the radial thrust generated when the driven gear is meshed, it is easy to cause eccentric wear and increase the gap between the shaft and bushing hole. Therefore, during operation, the oil leakage will occur due to the increase of the gap, and the oil supply will be reduced. After the drive shaft and bushing are worn, the matching clearance can be restored by repairing the journal or bushing.

When the journal wear is slight, only the old bushing needs to be pressed out and replaced with a new bushing, and the shaft can generally not be repaired, so that the mating clearance can be restored to the allowable range. When the wear of the shaft and bushing is serious and the mating clearance increases greatly, not only the bushing should be replaced, but the shaft should also be chrome-plated or vibratory surfacing to increase the diameter, and then ground to the standard size to restore the matching requirements of the journal and the bushing.

2. Repair the inner cavity of the pump casing and gear teeth after wear.

After the inner cavity of the pump casing and the gear teeth are worn, it has a great impact on the pump oil volume, which will cause the pressure difference between the oil pump inlet and outlet chamber to decrease, so that the oil scraping and oil pressure of the gear teeth will be reduced, resulting in a decrease in the oil supply pressure and a decrease in the pump oil volume. At this time, the wear of the inner cavity of the pump casing is generally repaired by the inner cavity setting method.

Secondly, due to the wear of the gear teeth in the direction of tooth thickness, the meshing gap of the main and passive gears increases, and its wear is characterized by heavy one-sided wear, so the gear can be turned over 180 degrees for use.

3. Repair the gear end face and pump cover after wear.

There is a certain gap between the end face of the gear and the inner plane of the pump cover, which is called the end face clearance. The wear caused by the contact surface between the gear end face and the inner plane of the pump cover during the work will increase the gap between the end face, and when the limit is exceeded, it will have a significant impact on the pump oil volume.

When the end face of the gear is worn, the end face can be smoothed, and the decomposition surface of the oil pump casing can be re-ground at the same time to ensure that the end face clearance of the pump is within the required range.

In the daily use of diesel generator sets, Ito Power reminds everyone that it is necessary to pay attention to correcting non-standard operation phenomena to avoid the occurrence of the above wear and tear, and the company should also start to formulate a systematic operation and maintenance specification, so that employees can repair Ito generators in a timely manner, so as to ensure the normal operation of the work.

LT215 wear-resistant repair agent can be used for cold-adhesive repair.

Several solutions to the wear and tear of the gear oil pump of the diesel generator set:

1. Repair the drive shaft and bushing of the gear oil pump after wear.

After the wear of the driving shaft and bushing of the gear pump, the matching gap increases, which will inevitably affect the oil volume of the pump. In this case, the method of repairing the shaft or bushing can be used to restore its normal mating clearance. If the wear of the drive shaft is slight, the old bushing can be pressed out and replaced with a standard size bushing, and the mating clearance can be restored to the allowable range.

If the drive shaft and bushing are seriously worn and the fit clearance is seriously exceeded, not only the bushing should be replaced, but also the drive shaft should be increased in diameter by chrome plating or vibration surfacing welding, and then ground to the standard size to restore the fit requirements with the bushing.

2. Repair of lubricating oil pump casing and repair of shell cracks.

The cracks in the oil pump casing can be repaired by casting 508 nickel copper electrode. The weld must be tight, and the flatness error of the joint surface between the air hole and the oil pump cover is not more than 0 05 mm.

3. Repair the wear of the bushing hole of the driving shaft and the driven shaft hole of the gear oil pump.

After the bushing hole of the driving shaft of the gear oil pump of the tanker truck is worn, the wear marks can be eliminated by reaming, and then the bushing can be enlarged to the corresponding size. The driven shaft bore wear is also reamed to eliminate the wear marks, and then the driven shaft is prepared according to the actual size of the reamed hole. Electric lubrication pump.

4. Repair the inner cavity of the pump casing of the gear oil pump.

After the inner cavity of the gear oil pump casing is worn, it is generally repaired by the inner cavity inlay method, that is, the inner cavity is enlarged and then inlaid with cast iron or steel bushing. After the sleeve, the inner cavity is enameled and the valve seat is repaired: there are two types of pressure limiting valves: ball valves and plunger valves.

After the ball seat is worn, a steel ball can be placed on the valve seat, and then the steel ball can be gently tapped with a metal rod until the ball valve is tightly closed to the seat. If the valve seat is seriously worn, it can be reamed to remove the wear marks, and then use the upper method to make it tight. After the piston seat is worn, a little valve sand can be placed and ground until it is tightly sealed.

5. Repair of gear oil pump cover.

Repair of the working surface of the oil pump: If the wear of the working plane of the KCB gear oil pump cover is small, the wear marks can be eliminated by manual grinding, that is, a little valve sand is placed on the platform or thick glass plate and then the pump cover is placed on it for grinding until the wear marks are eliminated and the working surface is flat. When the wear depth of the working plane of the pump cover exceeds 0 1 mm, it should be repaired by turning first and then grinding.

Oil pumps are generally not recommended to be repaired, only replaced. Improper remediation has serious consequences.