The piston sliding or crawling of the hydraulic cylinder of the brick making machine will make the hydraulic cylinder work unstable. The main reasons are as follows:
(1) Poor lubrication or poor machining of hydraulic cylinder bore. Because the piston and cylinder barrel, guide rail and piston rod have relative movement, if the lubrication is poor or the bore diameter of hydraulic cylinder is out of tolerance, the wear will be aggravated and the straightness of cylinder center line will be reduced. In this way, when the piston works in the hydraulic cylinder, the friction resistance will be large or small, resulting in sliding or crawling. The elimination method is to repair and grind the hydraulic cylinder first, then prepare the piston according to the matching requirements, repair the piston rod, and install the guide sleeve. This is related to the brick making machine in the production process of technical problems. Therefore, it is very important to choose a brick machine manufacturer with excellent technical team.
(2) The inside of hydraulic cylinder is astringent. This will be very disadvantageous to the work of the brick making machine. The internal parts of the hydraulic cylinder are improperly assembled, deformed, worn or out of tolerance of form and position, and the action resistance is too large, so that the piston speed of the hydraulic cylinder changes with the stroke position, resulting in sliding or crawling. For a block making machine, most of the reasons are due to the poor assembly quality of parts, the surface has scars or iron chips produced by sintering, which increases the resistance and reduces the speed. For example: the piston is not concentric with the piston rod or the piston rod is bent, the hydraulic cylinder or piston rod is offset from the installation position of the guide rail, and the sealing ring is installed too tight or too loose. The solution is to repair or adjust, replace damaged parts and remove iron filings.
(3) The quality of seal is directly related to slip or creep. When the O-ring is used under low pressure, compared with the U-ring, due to the higher surface pressure and the larger difference between the static and dynamic friction resistance, the O-ring is easy to slip or crawl The surface pressure of U-shaped sealing ring increases with the increase of pressure. Although the sealing effect is also improved, the difference between dynamic and static friction resistance becomes larger, and the increase of internal pressure will affect the rubber elasticity. Due to the increase of contact resistance of lip edge, the sealing ring will tip over and the lip edge will be extended, which is easy to lead to sliding or crawling. In order to prevent it from tipping, support environment protection can be used to maintain its stability.
(4) Air enters the hydraulic pump or cylinder. Compression or expansion of air can cause the piston to slip or creep. The elimination measures are to check the hydraulic pump, set up a special exhaust device, and quickly operate the whole stroke for several times.