Hot Runner Coil Heater Taxonomy
In general, the hot runner system is divided into single-headed hot runner system, hot runner system and valve hot runner system. Single-headed hot runner system consists of a single nozzle, nozzle head, nozzle plate, temperature control system and other components.
Single hot runner system plastic mold structure is simple. Molten plastic is injected into the nozzle plate by the injection molding machine and reaches the nozzle tip through the nozzle before it is injected into the cavity. Need to control the size of d, D, L and by adjusting the size of the nozzle plate thickness, the fixed mold plate pressing the end face of the nozzle plate to control the nozzle axial displacement, or direct use of the nozzle nozzle against the nozzle plate Face, but also can achieve the same purpose. A fixed position in the fixed plate is provided with a guide slot, so that the power cord leads from the mold and installed in the mold on the terminal block connection.
Hot runner system plastic mold structure is more complicated. The molten plastic is injected into the nozzle plate by the injection molding machine, flows through the hot runner plate to the nozzle and reaches the nozzle head, and is then injected into the cavity. Hot runner system nozzle and the template has a radial dimension D1 requirements and axial size limit requirements. Nozzle head and the die with a radial dimension d fit requirements to ensure that the molten state of the plastic does not overflow to the non-cavity parts, and require the hardness of the die-hardened block about 50HRC. The distance L between the parting surface and the axial positioning surface of the hot nozzle must be strictly controlled. The size should be determined according to the actual distance L 'of the nozzle at normal temperature plus the actual extension amount ΔL of the nozzle at the normal working temperature of the mold. In order to ensure that the nozzle and the hot runner plate fit reliably without causing deformation of the hot runner plate, an adjustment pad is arranged above the top of the nozzle, which together with the axial positioning surface of the nozzle limits the movement of the nozzle in the axial direction, And effectively control the possible deformation of the hot runner plate. At room temperature, the adjustment pad and the hot runner plate and the fixed mold control plate 0.025mm gap between the gap so that the mold is heated, the operating temperature of the state when the adjustment mat just pressed. The hot runner system locating seat and locating pin control the position of the hot runner plate in the mold. Locating and fixing plate with a radial dimension D2 requirements, and the depth of h must be controlled accurately, the positioning of the axial play a role in supporting the hot runner plate, the injection machine directly to withstand the injection pressure. Pins and hot runner plate with a fixed plate requirements. There must be enough clearance between the runner plate and the formwork to wrap the insulation material. The hot runner plate and the fixing plate must be provided with sufficient wiring slots for the power cord to be led out of the mold to be connected to the wiring holder mounted on the mold. There is a radial dimension D1 between the nozzle plate and the stationary plate, so that the injection head of the injection molding machine cooperates well with the nozzle plate on the mold. In the vicinity of the hot runner plate, the fixed template, the hot runner plate fixing plate, fixed plate fixing plate screwed together to enhance the rigidity of the hot runner plate.
Valve gate hot runner system The most complex plastic mold structure. It has the same structure with the common plastic mold of hot runner system, and more than one set of valve needle control valve needle opening and closing movement. The transmission device is equivalent to a hydraulic cylinder. The hydraulic device of the injection machine is connected with the mold to form a hydraulic circuit to realize the opening and closing movement of the valve needle and control the injection of molten plastic into the cavity.
