Structure and principle of plywood hot press machine
The plywood hot press machine is the core equipment for plywood production, and its structure and principle directly affect the quality and production efficiency of the plywood. The main body of the equipment consists of upper/lower hot pressing plates, sprocket drive devices, guide rail systems, and hydraulic control components. The upper and lower hot pressing plates are made of high-strength alloy steel and covered with a high-temperature resistant coating to ensure uniform heat transfer; The sprocket drive device drives the chain through a motor to achieve precise movement of the lower hot press plate along the guide rail, with a horizontal displacement accuracy of ± 0.5mm. The guide rail system adopts a dual guide rail structure to support the smooth lifting and lowering of the hot press plate, avoiding plate displacement.
The hydraulic system is the power core of the hot press, which injects hydraulic oil into the oil cylinder through a high-pressure pump to drive the upper hot press plate to press down. The pressure range covers 400-800 tons, meeting the needs of multi-layer veneer pressing. Modern models generally integrate elastic compression systems, using a combination design of compression rollers and compression springs, combined with guide rods to achieve precise pressure control, ensuring uniform force distribution on each layer of the board.
The heating system is the key to the hot pressing process, and the equipment uses electric heating oil furnaces or coal-fired boilers as heat sources, with a stable working temperature of 120-180 ℃. The hot press plate is embedded with a serpentine heat transfer oil pipe inside, which achieves efficient heat transfer through a circulating pump. Some models also integrate a jet drying device to pre treat the slab and shorten the heating time.
The hot pressing process is divided into three stages: preheating, pressurization, and forming. In the preheating stage, the L-shaped positioning plate is fixed by an electromagnet to ensure the alignment of the slab; During the pressurization stage, the hydraulic system drives the upper hot pressing plate to press down, and the elastic mechanism buffers the pressure impact; During the molding stage, the sprocket drives the hot pressing plate to move, and with the help of a glue cooling and solidification mechanism, the single cycle time is shortened to within 25 minutes, which is 40% more efficient than traditional models.
