What are the combinations of vacuum-forming machines?
The clamping device of the vacuum forming machine: The clamping device is preferably automatically controlled to move quickly, which helps to improve the quality and efficiency of the product. When the plastic sheet is formed, the sheet is fixed on the clamping device. Clamping devices that facilitate the fixing of sheets of various sizes are generally used in general-purpose and composite thermoforming machines for thermoforming. Some of them equipped the entire forming apparatus with a clamping frame.
The vacuum forming machine's clamping device can be divided into two types: one is the frame type, and the other is the split type. The frame-type clamping device is composed of an upper frame and a lower frame. The sheets are sandwiched between the two structures. When the frame is opened, the lower edge usually remains fixed. The lower part of the upper boundary of various types of single-station molding machines is directly fixed on the molding chamber. When the frame size is large, the manual and semi-automatic forming machines that load the parison by hand and take out the finished product are equipped with safety operation devices within the frame opening range. For this purpose, two rubber-covered rollers are used, which are pressed against each other by springs, and are equipped with pressure regulating devices. The clamping of the continuous pull forming machine is the joint action of the zippers on both sides and the front and rear brakes.
Heating vacuum forming machine equipment:?In the vacuum forming process of thermoplastic sheet and film, one of the main functions is sheet heating. The duration and quality of electric heating depend on the structure of the heater, the thermal inertia of the temperature heat transfer behind the radiant surface, the distance between the plate and the heater, the radiant energy absorption coefficient, the characteristics of the heater surface, and the thermophysical properties of the material. Standard heaters include electric heaters, crystal radiators, and infrared heaters.
Vacuum forming machine equipment: The vacuum system is composed of a vacuum pump, gas tank, valve, pipeline, and vacuum gauge. In vacuum forming, a separate vacuum pump is usually used. The vacuum degree of the pump should reach above 0.07 ~ 0.09 Mpa (520 MHG). The gas storage tank is usually a cylindrical storage tank welded by thin steel plates with an oval bottom. The gas storage tank's capacity should be at least half of the ability of the largest compartment. Appropriate valves must be installed on the vacuum line to control the narrow vacuum capacity. Larger or faster molding equipment is usually as large as 2-4KW. The size of the central vacuum system depends on the specific production and development requirements of the factory.
The compressed air equipment of the vacuum forming machine: the pneumatic system can be composed of the forming machine itself with a compressor, the gas storage tank, the main pipeline gas is collecting pipe of the workshop, and the valve. The molding machine requires compressed air with a pressure of 0.4-0.5 MPa, and piston air compressors are widely used in various vacuum suction molding machines. A large screw air compressor can also provide it. In addition to the large amount of compressed air that should operate for molding, there is also power when part of the compressed air is used for demolding, external cooling of primary products, and the operation of machine parts such as mold frames and running plates.
Cooling vacuum forming machine equipment: vacuum forming products often need to be cooled before demolding. Ideally, both the inner surface and the workpiece's outer surface contact the mold are cooled, and a mold with an internal cooling coil is preferably used. If natural cooling is used in production, it can obtain annealed details conducive to improving the parts' impact resistance. Although water cooling has higher production efficiency, the internal stress of the components is relatively large.
Demoulding equipment of vacuum blister forming machine: Demoulding is to remove the product from the mold. Generally, whether it is a female mold or a male mold, due to cooling shrinkage, the product is tightly attached to the mold most of the time, so it is demolded by vacuum suction or blowing in the opposite direction. Especially for molds or concave molds with a slight draft angle.