Analysis of common problems of hot press

Hot press is the main machine to produce wood-based panel, and its performance will directly affect the quality of wood-based panel production. Therefore, wood-based panel manufacturers must be careful when choosing the hot press, otherwise the loss will be irreparable. The quality of the hot press is closely related to the pressure of the machine. The hot press used now is generally hydraulic, so the hydraulic cylinder is the main part of the whole machine;

In the process of using the hot press, we usually encounter some faults, which directly affect the normal production and the quality of wood-based panels. So we will understand how to deal with the unstable working of the hydraulic cylinder when the piston of the hydraulic cylinder slips or crawls. First of all, we should find out the cause of the accident, and we will analyze it;

(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 the hydraulic cylinder is out of tolerance, the wear will be aggravated, and the straightness of the cylinder barrel centerline 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 and grind the piston rod, and configure the guide sleeve.

(2) The hydraulic cylinder is stagnant. Improper assembly of internal parts of hydraulic cylinder, deformation, wear of parts or out of tolerance of shape and position, and excessive action resistance make the piston speed of hydraulic cylinder change with different stroke position, and slip or crawl. Most of the reasons are due to poor assembly quality of parts, surface scars or iron chips produced by sintering, which increase the resistance and decrease the speed. For example: the piston and the piston rod are not concentric or the piston rod is bent, the installation position of the hydraulic cylinder or piston rod to the guide rail is offset, the sealing ring is installed too tightly or too loose, etc. The solution is to repair or adjust again, replace damaged parts and remove scrap iron.

(3) The hydraulic pump or cylinder enters the air. Air compression or expansion can cause the piston to slip or crawl. The elimination measures are to check the hydraulic pump, set up a special exhaust device, quickly operate the whole stroke and exhaust several times.

To solve the problem, we should first find the cause of the problem, so that it can be solved with pertinence. And the hot press is the most important equipment in the production of wood-based panels, once there is a failure, it is necessary to timely repair, so as not to delay production.