Repair method of 75 pump used by the hottest truck

Repair method of 75 pump used by truck crane

repair method of 75 pump used by truck crane:

75 pump used by truck crane (ZB type, the same below) is through 7 plungers, and the EU will make a big move in March nbsp; Are Chinese packaging material export enterprises ready? Constantly changing the position (linear movement) in the cylinder block hole to absorb and compress the oil. When the plunger is seriously worn, the fitting clearance between the plunger and the cylinder block hole will increase, and the hole diameter will become very irregular, which will reduce the pressure of the pump, reduce the efficiency, and even make it unusable. During the maintenance, it was found that many old 75 pumps can still be repaired. The repaired 75 pump can generally be reused for 2-3 years. The method of repair can avoid complexity and simplify. Under normal circumstances, the allocation of hydraulic components cannot be replaced by other materials, and the silver coupling parts cannot be interchanged, but in practice, some 1 Let's see. It is feasible to redeploy the plunger of the pump for repair. As for 75 pump, it is not easy to repair the inside of the cylinder block, while the plunger is easier to repair, so the function of the pump can be restored by repairing the plunger

there are three repair methods:

(1) look for plungers with relatively small wear (7 in a group) in a number of used 75 pumps, then re pair and combine them according to the size of the plunger and the cylinder block, and finally grind them

in this process, it is an important reference index for quality control and utilization design to accurately measure the outer diameter dimension and ellipse of the plunger with an outer micrometer and an inner micrometer for many times, as well as the bore diameter and taper of the cylinder block hole, so that the matching clearance between the selected plunger and the cylinder block hole can reach 0.02_ 0 4mm. The pump so selected and repaired can generally be used for more than 2 years

(2) when there is no redundant old pump, measure the outer diameter of the plunger and the hole diameter of the cylinder block, and then reassemble and pair the ones with small fitting clearance and serious wear respectively. The plunger with serious wear can be electroplated to reach the required size (if the coating is thick, it can be finely ground to the required size); After the plunger is matched with the cylinder block hole, mark it and grind it one by one. Note: during electroplating, do not coat the surface of the ball in the slipper at one end of the plunger. The plunger and cylinder block hole with small matching clearance and meeting the requirements can continue to be used

(3) when the plunger is seriously worn, especially for the plunger with hard scars on the surface, its part size can be measured and re machined. When turning, we should pay attention to setting aside grinding allowance and quenching and tempering treatment. According to our experience, we should spend less money and repair expensive hydraulic components such as 75 pump without affecting the safety performance of the whole machine