Quality Inspection and judgment of hydraulic cylinder parts

Here below is the details of how to insepct the hydraulic cylinder parts

(1) The inner surface of the hydraulic cylinder barrel

The inner surface of the hydraulic cylinder tube has very shallow linear friction scratches or spot marks, which are allowed and are not harmful to use. If it is a longitudinal strain, the inner hole must be ground, or it can be corrected with very fine sandpaper or whetstone. When the longitudinal strain cannot be corrected, the cylinder must be replaced with a new one.

(2) Hydraulic Piston rod

Strain or scar on the sliding surface of the piston rod that moves relative to the sealing ring, the judgment and treatment method is the same as the inner surface of the cylinder. However, the sliding surface of the hydraulic piston rod is generally plated with hard chrome, it is chrome plated bar. If a part of the coating falls off due to wear to form deep longitudinal marks, the external oil leakage will have a great impact. At this point the old coating must be removed, re-chromed and polished. Chrome plating thickness of the hard chrome plated shafting is 20microns to 50 microns upon request.

(3) Seals

To check the piston rod and piston seal, firstly observe whether the lip of the seal is damaged and the wear of the sealing friction surface. When it is found that there are slight scars on the lip and wear on the friction surface, it is best to replace the seal with a new one.

(4) Guide sleeve

There are some scars on the inner surface of the guide sleeve, which has little effect on the use. However, if the scar is more than 0.2mm, it should be replaced with a new guide sleeve.

(5) Piston

When there are slight scars on the surface of the piston, it will not affect the use; if the scar is more than 0.2mm, it should be replaced with a new piston. Also, check the piston for cracks caused by collision with the cylinder head. If so, the piston must be replaced.

(6) Others

The inspection of other parts varies with the structure and use of the hydraulic cylinder. However, the inspection should pay attention to whether there are cracks in the end cover, earrings, hinge shaft, and whether there is any abnormality in the thread of the top of the piston rod and the thread of the oil port.