① Scar caused by foreign matter mixed in during assembly. Before the total assembly of the hydraulic cylinder, all parts must be fully deburred and cleaned. When the parts are installed with burrs or dirt, foreign matter is easy to embed into the cylinder due to the "strength" and the weight of the parts. wall surface, causing scars.
② Scars in the installation parts When installing the hydraulic cylinder, the parts such as the piston and the cylinder head are of large mass, large size and large inertia. Even if there is a hoisting device to assist in the installation, because the specified fitting clearance is small, no matter what, it will be hard to invest. Therefore, when the end of the piston or the boss of the cylinder head hits the inner surface of the cylinder wall, it is very easy to cause scars. The solution to this problem: For small products with large quantities and large batches, use special assembly guide tools during installation; for heavy, coarse, and large large and medium-sized hydraulic cylinders, only careful and careful operation can be avoided.
③The scars caused by the contacts of the measuring instrument are usually used to measure the inner diameter of the cylinder with an inner diameter dial indicator. The measuring contacts are inserted into the hole wall of the cylinder while rubbing, and the measuring contacts are mostly made of high-hardness wear-resistant cemented carbide. Generally speaking, the slender scratches that are not deep in the measurement are slight and do not affect the running accuracy, but if the size of the measuring rod head is not adjusted properly, the measuring contacts are hard embedded, which will cause more serious scratches. The countermeasure to solve this problem is to measure the length of the adjusted measuring head first. In addition, use a piece of paper tape with holes only at the measuring position to be attached to the inner surface of the cylinder wall, that is, the above-mentioned shape scratches will not be generated. . Slight scratches caused by measurement can generally be wiped off with the back of an old emery cloth or horse dung paper.
