Forklift gear pump maintenance methods and troubleshooting

Today we talk about the repair method of the parts on the forklift and the means to eliminate some faults.

Forklift gear pump parts repair methods are:

1. Forklift gears: The outer gears of the gears are worn and glued so that their radial clearances become larger. The lighter ones have no noticeable effect on use. In severe cases, the gears should protect the safety of other parts of the forklift.

2. The wear on both sides of the gear, if it is not serious, it will only play a line. Grinding will be used to grind the burr marks; when the wear is serious, it can be polished off. However, as long as one gear end wears, the other gear must also be ground at the same time to ensure that the difference between the two gears is about 0.005mm. Grinding should also pay attention to the accuracy of the end face and hole, end face and end face. After grinding, apply oil stone to sharpen sharp burrs but not chamfer.

3, oil pump gears are all working in one direction, so the tooth surfaces are single-sided wear. Gears with worn tooth surfaces can be removed from the burrs with Whetstone, and the meshing orientation of the gears can be reversed to restore the working performance of the oil pump.

4. Forklift gear bearing frame: When the end face wears or picks up the line, four bearings can be placed on the surface grinding machine. When the non-gear contact surface is used as the reference, the end surface will be ground once.

5, the inner hole is generally less wear, if serious wear, grinding or grinding the aperture to repair the size, optional needle roller.

6. When worn, scratched and grooved with sleeves or axially floating sleeves, the damaged surface can be polished. The method is to put no 400-600 on the smooth surface of the paste, plus wash oil or wax gently on the side plate surface rotation for polishing.

7, forklift gear pump body: pump body wear generally occurs in the suction chamber, some oil pumps can be used on the structure of the transposition method to repair, that is, the pump body around its axis 180 °, so that the suction chamber into the pressure chamber to restore its work ability.

8, can not be used to transpose the repair of the oil pump body can be repaired with copper insert method.

9. When the gear is ground due to wear on the end face, the rear end of the pump body must be ground to an appropriate thickness in order to maintain the axial clearance.

Forklift truck unloading fault troubleshooting method:

When the cpcd5aiiz type forklift has a gear in use, there is a strong impact of abnormal sound. Because the car is equipped with a hydraulic shift fixed shaft variable speed reducer or differential loose.

The drive shaft of the main reducer rotates its input shaft by hand and finds a free rotation gap of nearly 30 degrees, so it is determined that the gear clearance of the main reducer is too large. Remove the main reducer and measure the clearance as 0.65mm (standard value 0.30-0.50mm). Adjust the position of the bevel gear so that the gear clearance with the bevel driving gear is 0.35mm. After refitting the test machine, there is still a shock phenomenon and an abnormal sound is caused when the gear is engaged. The degree is only slightly reduced compared with the original, but the failure remains.

To do this, remove the drive shaft again and leave the transmission at no load. Start the engine and repeat the gear-hanging, blocking, and lifting gear tests. It is found that the abnormal sound generated by the gear is still present and the transmission has obvious vibration. Check the transmission mounting bolts, no looseness. Judging from this phenomenon, the fault should be inside the transmission. The decommissioning, cleaning and inspection of the transmission were dismantled, and the taper roller bearings of the main and driven shafts of the reverse gear and the forward gear clutch were found to be loose. By adjusting the bearing to an appropriate gap by increasing or decreasing the shims, and reassembling the test machine, the phenomenon of shock and abnormal noise of the shock absorber is weakened, but the failure phenomenon still exists.

After such a detailed inspection has failed to find the root cause of the failure, is there any defect in the design or manufacture of this type of forklift? Therefore, the forklifts produced by the same model of the plant were found to carry out road tests for gearing, pushing, and lifting gears. As a result, it was found that there were slight impacts on the gears, but the severity was different. Therefore, the search for the cause of the fault should be on the hydraulic control part of the transmission. Refer to the transmission control principle diagram and the parts map of the transmission. Know that the piston return of the clutch is achieved by the spring preload. Therefore, at the moment when the gear is engaged, the main clutch may have a situation in which the pressure controls the flow of the oil, so that the preload of the spring is quickly overcome so that the drive piece and the follower pad are engaged too fast and generate a gear impact. In order to verify this idea, it is necessary to make certain modifications to its hydraulic control line. An adjustable flow valve is connected in series between the reversing valve and each clutch piston to control the flow rate so that it can achieve the purpose of stable engagement.

The above is some tips on how to repair some parts of a forklift truck and quickly troubleshoot.