Transparent plastics, because of their high transmittance, are bound to require strict surface quality of plastic products, and can not have any defects such as markings, pores, whitening, fog halo, black spots, discoloration, poor gloss, etc. Therefore, in the entire injection molding process, the design of raw materials, equipment, molds, and even products should be paid great attention to and put forward strict. To special requirements. Secondly, transparent plastics are mostly of high melting point and poor fluidity, so […]
First inspection and self inspection in injection molding production
1) Before production, the operator must submit the first mold product to the inspector for self-inspection and then to the inspector for first inspection. Only after the inspector notifies that it is qualified, can the mass production be carried out. The first mold sample should be left on the injection molding machine for self-inspection in production.
2) If the products in production do not meet the quality requirements, the monitor should be […]
Injection system is one of the main components of injection molding machine, generally there are three main methods: plunger, screw, screw pre-plastic plunger injection. Now widely used is screw type. The effect is that in a cycle of the injection machine, a certain amount of plastic can be heated and plasticized within a specified time, and the molten plastic can be injected into the mold cavity through a screw under a certain pressure and speed. After the injection, […]
The injection molding process includes preparation before molding, injection process and post-processing of plastic parts.
Preparations before molding include the inspection of raw material appearance and the determination of technological properties, preheating and drying, cleaning of injection machine barrel, preheating of inserts and selection of release agent when demoulding is difficult. Sometimes it is necessary to preheat the mold.
During molding, powdered or granular materials are fed from the hopper into the high-temperature barrel for melting and plasticizing to become viscous […]
The complexity of the properties of plastic materials determines the complexity of the injection molding process. And the performance of plastic materials varies greatly because of different varieties, brands, manufacturers, and even batches. Different performance parameters may lead to completely different molding results.
The melt flows into the cooling cavity, dissipating heat due to heat conduction. At the same time, the heat generated by shearing may lose more or less heat than heat conduction, depending mainly on the […]
The possible reasons for the deformation of injection molded parts are:
bending is due to excessive internal stress in injection molded parts.
mold filling speed is slow.
plastic material in cavity is not enough.
plastic temperature is too low or inconsistent.
injection molded parts are too hot at the time of ejection.
the temperature of cooling is insufficient or the temperature of the moving and fixed die is inconsistent.
the structure of injection molded parts is unreasonable (such as stiffeners are concentrated on one side, but […]
“Plastic properties are the basis of injection molding technology”. Mastering the technological properties and characteristics of various plastics is a basic professional knowledge that every injection molding worker must know. The performance of plastics is the basis for setting “injection molding process conditions”. It is also the reason that must be considered when analyzing the quality problems and abnormal phenomena in the process of injection molding. One of the elements.
PP, commonly known as polypropylene, is also known as “100 […]
Injection molding is a kind of production behavior that plastic particles are molded into predetermined shapes by heating and melting. In this process, many factors of production have an important impact on the quality and production efficiency of the final plastic products.
Although different materials and different products have a variety of injection molding techniques, but we can summarize the process of injection molding parameters in the final product of the impact of various factors, so as to adjust the […]
PC: PC is the abbreviation of polycarbonate, with excellent electrical insulation, elongation, dimensional stability and chemical corrosion resistance, high strength, heat resistance and cold resistance, but also has self-extinguishing, flame retardant, non-toxic, coloring and other advantages.
Applications: Broad-wave transparent optical instruments; flame-retardant and environmentally friendly telecommunications appliances; surface metallized automotive parts; food containers with low residual harmful substances; anti-cracking and embrittlement medical devices
ABS: (ABS resin) (acrylonitrile-styrene-butadiene copolymer), good rigidity, high impact strength, heat resistance, low temperature resistance, chemical resistance, mechanical […]
The price of the export mold will be more expensive, but it is expensive because the standard is different. The American Plastics Industry Association (SPIAN-102-78) divides the molds into five categories. Each of these five types of molds has its own requirements, and this classification of molds can only be applied to molds with 400 tons or less of injection molding machines.
The cycle can be up to 1 million times for high production. The best mold material is […]