The installation of Hitachi excavator hydraulic cylinder in construction machinery shall consider that it is a device that directly drives the load, that is, it is related to the size, nature and direction of the load. It must be considered during installation, such as:
① The connected base must be rigid enough. If the base is not firm, when pressurized, the rigid cylinder will be arched upward, resulting in bending or bending of the piston rod.
② For the large stroke hydraulic cylinder with large diameter and stroke of more than 2 ~ 2.5m, the guide support ring of the piston rod and the middle support of the cylinder barrel must be installed to prevent the deflection of the piston rod and cylinder barrel. If it is flexed, the gap between the cylinder block and the piston rod, the piston rod and the guide sleeve will be uneven, resulting in uneven wear and strain of the sliding surface; Make the hydraulic cylinder leak internally and externally, and even make the hydraulic cylinder unavailable.
③ The earring hydraulic cylinder takes the earring as the fulcrum. It can swing in the plane perpendicular to the earring and do linear reciprocating motion at the same time. Therefore, the axial direction of the connecting shaft hole at the top of the piston rod must be consistent with the direction of the trunnion hole. Otherwise, the hydraulic cylinder will be subjected to the bending load with the trunnion hole as the fulcrum, and sometimes the head thread at the rod end will be broken due to the bending of the piston rod; Moreover, due to the reciprocating motion of the piston rod in the bending state, it is easy to strain the cylinder surface, resulting in uneven wear of the guide sleeve and oil leakage.
④ When the trunnion hydraulic cylinder is required to rotate freely around the trunnion hole, universal joint or universal coupling can be used. After the universal joint is adopted, the hydraulic cylinder can swing freely as a whole, which can minimize the twisting phenomenon.
⑤ The installation method of hairpin shaft hydraulic cylinder shall be the same as that of trunnion hydraulic cylinder, because the hydraulic cylinder takes the hairpin shaft as the fulcrum and makes linear reciprocating motion while swinging in a plane perpendicular to the hairpin shaft. Therefore, the connecting pin at the top of the piston rod should be in the same direction as the hairpin shaft. If the connecting pin is perpendicular to the hairpin shaft, the hydraulic red will be deformed and bent, and the threaded part at the top of the piston rod will be broken. In addition, due to the action of transverse force, the piston rod guide sleeve and piston surface are prone to uneven wear and strain, which is the cause of damage and oil leakage.
