Analysis of common faults of hot press

Hot press is the main machine for producing wood-based panel, and its performance is directly related to the production quality of wood-based panel. Therefore, wood-based panel manufacturers must be careful when choosing hot press, otherwise its loss will be irreparable. The quality of hot press has a lot to do with the pressure of the machine. The hot press used now is usually hydraulic, so the hydraulic cylinder is the main part of the whole machine;

In the process of using the hot press, there are usually some faults, which directly affect the normal production and the quality of wood-based panel. So let's understand how to deal with when the hydraulic cylinder piston slips or crawls, which will make the hydraulic cylinder unstable. First, we should find out the cause of the accident. Let's analyze it;

(1) Poor lubrication or poor machining of hydraulic cylinder bore. Because the piston and cylinder, guide rail and piston rod have relative motion, if the lubrication is poor or the bore diameter of hydraulic cylinder is out of tolerance, it will aggravate the wear and reduce the straightness of cylinder center line. In this way, when the piston is working in the hydraulic cylinder, the friction resistance will be large or small, resulting in sliding or crawling. The elimination method is to grind the hydraulic cylinder first, then prepare the piston according to the matching requirements, grind the piston rod and configure the guide sleeve.

(2) The hydraulic cylinder is astringent inside. The internal parts of the hydraulic cylinder are improperly assembled, the parts are deformed, worn or the tolerance of shape and position is out of limit, and the action resistance is too large, which makes the piston speed of the hydraulic cylinder change with the different stroke position, resulting in sliding or crawling. 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 is not concentric with the piston rod or the piston rod is bent, the installation position of the hydraulic cylinder or piston rod is deviated from the guide rail, and the sealing ring is installed too tight or loose. 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 creep. The elimination measures are to check the hydraulic pump, set up a special exhaust device, and quickly operate the whole stroke to exhaust several times.

To solve the problem, we should first find the cause of the problem, so that it can be targeted. Moreover, the hot press is the most important equipment for the production of wood-based panel. Once there is a fault, it should be repaired in time to avoid delay in production.