Plastic injection molding is a molding method of injection and molding, and its equipment is called plastic injection molding machine, or injection molding machine for short. Plastic injection molding machines are the main molding equipment for making thermoplastics and thermosets into various plastic products. Ordinary plastic injection molding machine refers to the most widely used single-screw or plunger horizontal, vertical or angle single-station injection molding machine for processing thermoplastics.
In the plastic extrusion molding equipment, the plastic extrusion machine is usually called the main machine, and the subsequent equipment plastic extrusion molding machine is called the auxiliary machine. After more than 100 years of development, plastic extrusion machine have been derived from the original single-screw, twin-screw, multi-screw, and even no-screw models. The plastic extrusion machine can be matched with various plastic forming auxiliary machines such as pipe, film, bar, monofilament, flat wire, packing tape, extruded mesh, plate (sheet), profiled material, granulation, cable coating, etc. to form various plastic extrusion molding production lines and produce various plastic products. Therefore, plastic extrusion molding machinery is one of the widely used models in the plastic processing industry.
Blow molding consists of two basic steps: first forming a preform, and then using compressed air (and a stretching rod) to radially inflate (and axially stretch) the parison to make it close to (stretch) the blow mold Cavity, giving the shape and size of the cavity to the product, and cooling it.
There are two types of molding: co-extrusion blow molding and co-injection blow molding; stretch blow molding includes injection stretch blow molding and extrusion stretch blow molding. Stretch blow molding can be divided into one-step method and two-step method.
Compression molding and transfer molding are the main molding methods for thermosets. The press for compression molding and the transfer molding machine for transfer molding are the main molding equipment for thermosetting plastics to make various plastic products. The function of the press is to apply pressure to the plastic through the plastic mold. If a fixed mold is used, it also has the function of opening and closing the mold and ejecting the product. The presses used for compression molding are divided into two categories: mechanical presses and hydraulic presses. Because the manufacture, operation and repair of the motor press are more complicated than the hydraulic press, and it is not suitable for the compression molding of large plastic parts, it is gradually eliminated. The presses used are basically hydraulic presses. The pressure medium of hydraulic press usually has two types: oil and water. The former is widely used in small and medium-sized equipment. Transfer molding equipment can use the same hydraulic press as compression molding, or a dedicated transfer molding machine. The transfer machine in a plastic moulding machine is actually a double-press hydraulic machine with two hydraulic cylinders. According to its structure, it can be divided into upper and lower double pressure type and right angle type.
There are only three types of plastic thermoforming methods for thermoforming machines, namely female mold forming, male mold forming and paired mold forming. The thermoforming machinery in a moulding plastic machine should be able to repeat the thermoforming production cycle according to a certain program to make exactly the same product. There are many types of thermoforming machines, there are manual, semi-automatic and automatic thermoforming machines. Thermoforming products are large in volume and small in quantity, so semi-automatic or manual thermoforming machines are suitable. On the contrary, if the volume of the product is small and the quantity is large, it is more appropriate to use an automatic thermoforming machine.