Hydraulic gear pump failure repair, take you up knowledge

As the use time increases, the gear pump in the hydraulic system may have insufficient pump oil or even oil pump failure, mainly due to excessive wear of the relevant parts. The wear parts of the gear pump mainly include the drive shaft and bushing, the passive gear center hole and the shaft pin, the pump casing inner cavity and gear, the gear end face and the pump cover. When the main technical specifications of the lubricating oil pump fail to meet the requirements, they should be disassembled and decomposed, the wear parts and extent should be ascertained, and corresponding measures should be taken to repair them. Let's take a look at the Dalan hydraulic system manufacturers together!

First, the repair of the drive shaft and bushing after wear

After the gear pump drive shaft and bushing wear, the matching clearance increases, which will affect the pump oil quantity. In this case, the normal fit clearance can be restored by repairing the drive shaft or bushing. If the drive shaft wears slightly, simply press the old bushing and replace it with a standard size bushing to match the clearance to the allowable range. If the drive shaft and bushing are severely worn and the clearance is severely exceeded, the bushing must be replaced, and the drive shaft should be chromed or vibrated to increase its diameter, then ground to standard size, and the bushing is restored. Coordination requirements.

Hydraulic gear pump 2. Repair of the crack of the lubricating oil pump casing Repair of the casing: The crack of the casing can be repaired by casting 508 nickel-copper welding rod. The weld must be tight and the air hole, and the flatness error of the joint surface with the pump cover is not more than 0.05 mm.

Repair of the drive shaft bushing hole and the driven shaft hole wear: After the drive shaft bushing hole is worn, the wear marks can be used to eliminate the wear marks, and then the bushing is enlarged to the corresponding size. The driven shaft hole wear also eliminates the wear marks by the reaming method, and then the driven shaft is prepared according to the actual size of the reamed hole;

Repair of the inner cavity of the pump casing: After the inner cavity of the pump casing is worn, it is generally repaired by the inner cavity inserting method, that is, the inner cavity is enlarged and then cast with cast iron or steel bushing. After the insert is set, the inner cavity is pulled to the required size, and the bushing of the extended end face is ground to make it flush with the pump casing joint surface.

Valve seat repair: The pressure limiting valve has two kinds of ball valve and plunger valve. After the spherical seat is worn, a steel ball can be placed on the valve seat, and then the steel ball is gently tapped with a metal rod until the ball valve is in close contact with the valve seat. If the seat is severely worn, it can be first reamed to remove the wear marks, and then the upper method is used to make it close. After the plunger seat is worn, a small amount of valve sand can be placed for grinding until it is tight.

Third, the repair of the pump cover

Repair of the working plane: If the working plane of the pump cover is less worn, the wear marks can be eliminated by manual grinding, that is, put a little valve sand on the platform or thick glass plate, and then put the pump cover on it for grinding until the wear marks are eliminated. The working surface is flat. When the working surface of the pump cover wears more than 0.1 mm, it should be repaired by turning and grinding first.

Repair of the drive shaft bushing hole: Repair of the drive shaft bushing hole wear on the pump cover is the same as the repair of the housing drive shaft bushing hole wear.

Fourth, the use of gears to flip

The gear pump gear wear is mainly in the tooth thickness, while the gear end face and the tooth top wear are relatively light. The gears are worn on one side in the tooth thickness, so the gear can be turned 180 degrees. When the end face of the gear is worn, the end face can be flattened while the joint surface of the lubricating oil pump casing is ground to ensure that the gap between the gear end face and the pump cover is within the standard range.