Production methods of plastic products

The production of plastic products generally includes plastic ingredients, molding, machining, joining, modification and assembly. The last four processes are carried out after the plastic has been formed into finished products or semi-finished products, also known as plastic secondary processing.
The forming of plastic products is the key link of plastic processing. Various forms of plastics (powder, pellets, solutions or dispersions) are made into products or blanks of the desired shape. There are more than 30 methods of molding. Its choice is mainly determined by the type of plastic (thermoplastic or thermosetting), the starting form, and the shape and size of the product. Commonly used methods for plastic processing thermoplastics include extrusion, injection molding, calendering, blow molding and thermoforming, etc. Plastic processing thermosetting plastics generally use molding, transfer molding, and injection molding. Lamination, molding and thermoforming are the shaping of plastics on flat surfaces. The above-mentioned plastic processing method can be used for rubber processing. In addition, there are castings using liquid monomers or polymers as raw materials. Among these methods, extrusion and injection molding are the most widely used and the most basic molding methods.
Mechanical processing of plastic product production Borrow plastic processing methods such as metal and wood to manufacture plastic products with very precise dimensions or small quantities. It can also be used as an auxiliary process for forming, such as sawing of extruded profiles. Because the performance of plastic is different from that of metal and wood, plastic has poor thermal conductivity, low thermal expansion coefficient and elastic modulus. When the clamp or tool is pressurized too much, it is easy to cause deformation, and it is easy to melt when heated during cutting, and it is easy to adhere to the tool. superior. Therefore, when plastics are machined, the tools used and the corresponding cutting speeds must be adapted to the characteristics of the plastics. Commonly used machining methods include sawing, shearing, punching, turning, planing, drilling, grinding, polishing, and threading. In addition, plastics can also be cut, perforated and welded with lasers.
Jointing in the production of plastic products Plastic processing methods for joining plastic parts include welding and bonding. Welding methods include hot air welding using electrodes, hot melt welding using hot electrodes, high-frequency welding, friction welding, induction welding, ultrasonic welding, and the like. The bonding method can be divided into flux, resin solution and hot melt adhesive bonding according to the adhesive used.