The hydraulic system of a hot press has two basic working requirements: applying pressure to the workpiece and driving the hot press plate to achieve a specific movement. The stability of quick closure and pressure holding is an important index to evaluate the performance of hydraulic system.
Since the heating and curing of the adhesive should be completed in the pressure holding stage, the fast closing speed is beneficial to the process and efficiency. On the one hand, it can reduce the heating of the slab under non-pressure, prevent excessive water loss on the surface of the slab, causing warping, and prevent the pre-curing of the adhesive, reducing the quality of the veneer. On the other hand, it can shorten the auxiliary time and improve the productivity of the press. In order to make the press open and close smoothly, it is generally set up with a mechanical synchronization device or a hydraulic system to maintain synchronization.
Hydraulic cylinder is the core part of hydraulic system, most of the wood processing press are using plunger hydraulic cylinder. The large diameter cylinder plunger is cast by alloy, which is characterized by high hardness, thick hardness layer, scratch resistance, and better performance than carbon steel heat treatment plunger; The small diameter cylinder plunger is mainly plated with hard chromium on the surface of carbon steel heat treatment, and the surface hardness layer is thin.
Because the hot press usually requires a fast opening and closing speed to withstand impact pressure, the cylinder must choose a higher strength material. For ordinary small diameter, long stroke hydraulic cylinder, seamless thick wall steel pipe can be used to manufacture. For some demanding cylinder block can choose casting or forging cylinder.
Usually wood processing and furniture manufacturing with the hot press work surface are larger, in order to make the pressure distribution uniform, but also taking into account the rationality of the structural arrangement, most of the use of multi-cylinder structure.
There are not many problems in the production of the hot press itself, but a large part of them are in the hydraulic system, such as oil leakage and failure to maintain pressure. A lot of knowledge and requirements about the hydraulic system can not be described here, but it must be paid great attention to when choosing.
