Mold injection molding is a processing method used in mass production of some complicated parts. Specific principle refers to: plastic raw material melted by heat is pushed by screw of injection molding machine into cavity of plastic mold under high pressure, after cooling and solidification, plastic molded product is obtained. Plastic mold is composed of a movable mold and a fixed mold. Movable mold is installed on movable mold plate of injection molding machine, and fixed mold is installed on fixed mold plate of injection molding machine. During injection molding, movable mold and fixed mold are closed to form a pouring system and cavity. When mold is opened, movable mold and fixed mold are separated to take out plastic product.
Essence of pressure casting (referred to as die casting) is to fill cavity of die casting mode with liquid or semi-liquid metal at a higher speed under action of high pressure, obtain castings after forming and solidifying under pressure. It is mainly high-pressure and high-speed filling of die-casting cavity, formed castings have advantages of good quality, high production efficiency, and excellent economic effects. In the end, die-casting parts are no longer in automobile industry and instrument industry, but gradually expanded to machine tool industry, electronics industry, daily hardware and other industries. Special door is fitted on rotating support frame through folding hinge ring. In order to reduce mass production cost, die-casting method is used for molding during production.
In refrigeration link of air conditioner, two parts play a key role, one is axial fan on outdoor unit, and the other is centrifugal fan on indoor unit. High-speed axial fan blades continuously discharge heat generated in the room to outside, while centrifugal fan blades continuously transport air cooled by air conditioner indoors. Noise level of air conditioner depends on dynamic balance coefficient of these two parts under high-speed operation. In order to ensure a low wind blade dynamic balance coefficient, in addition to requiring parts to have good structural properties, there are also strict requirements on casting system of mold, and each gate must be balanced with feed. Because wind blade contains glass fiber and material has high hardness, use of traditional hot runner system is easy to wear beryllium copper nozzle core and gate, resulting in inconsistent feed of each gate and unstable dynamic balance of formed parts. Therefore, it is of great significance to develop a suitable hot runner system for wind blades containing glass fibers.
In order to make metal workpiece have required mechanical properties, physical properties and chemical properties, in addition to reasonable selection of materials and various forming processes, heat treatment processes are often indispensable. Steel is the most widely used material in machinery industry. Microstructure of steel is complex and can be controlled by heat treatment. Therefore, heat treatment of steel is main content of metal heat treatment.
DMC 2020 China International Mold Technology and Equipment Exhibition and 2020 Shanghai International Automobile Mold and Forming Process Equipment Exhibition have been held at National Convention and Exhibition Center (Shanghai Hongqiao) from October 10-13, 2020. For more than 30 years, DMC has developed and grown along with progress of China's mold industry, has achieved an international status as an authoritative professional integrated platform for integrated precision machining, mold manufacturing and forming equipment recognized by global exhibition and industry circles. In post-epidemic era, DMC2020 will build stage of entire industry chain with harder work and greater passion, realize new responsibilities and move on to a new journey.
1. This product is a transparent plastic part, with high quality requirements for wire clamping and appearance. 2. Average wall thickness is only 2.3mm, and customer requires a cycle of 70S. 3. Customer accepts that front mold undercut adopts elastic front mold structure, large side undercut of drawer rear mold adopts a large inclined top to drive a small inclined top structure.
Car rearview mirrors are divided into exterior rearview mirrors and inner rearview mirrors. Exterior rearview mirrors of different models have different shapes and structures, and outer shell is an important appearance part of rearview mirror. In order to meet functional, appearance and economic requirements of automotive products, structure of rear-view mirrors tends to be beautiful, refined and integrated. One-piece shell reduces number of rear-view mirror assembly parts, number of molds required, and production costs, making it the first choice for rear-view mirror structure design. At present, there are more domestic researches on split housings, but less research on design of integrated housings. Now we introduce design of an injection mold for an integrated housing of an automobile rearview mirror.
PCB guide plate product is shown in Figure 1. Maximum size of product is 254.84 mm * 217.70 mm * 57.00 mm, average thickness of plastic part is 2.50 mm, material of plastic part is ABS, shrinkage rate is 1.005, and weight of plastic part is 219.60 grams. Technical requirements of plastic parts are that there must be no defects such as peaks, dissatisfaction with injection molding, flow lines, pores, warpage deformation, silver streaks, cold materials, jet lines, etc.
Maintenance work must understand operation method of equipment, have some basic knowledge of injection molding, and will use injection molding machine correctly. If you do not know how to operate injection molding machine, maintenance work is very difficult, and fault may be unreliable. Circuit board and electrical components in injection molding machine are affected by factors such as high temperature, environment, and time for a long time, working point of device is shifted, aging degree of components is within normal range. Therefore, debugging injection molding machine is also one of essential basic skills in maintenance work. Understanding working procedures of injection molding machine, debugging electronic circuit and hydraulic circuit of injection molding machine are very important links.
Green single-door refrigerator drawer product diagram is shown in Figure 1. Maximum dimensions of product are 492.40 mm * 284.95 mm * 194.42 mm, average thickness of plastic part is 2.50 mm, plastic part material is PP+%25K, shrinkage rate is 1.009, weight of plastic part is 885 grams. Technical requirements for plastic parts are that there must be no defects such as peaks, insufficient injection molding, flow lines, pores, warpage deformation, silver streaks, cold materials, jet lines, etc.