Irradiation lamp holder injection mould
The product of the irradiation lamp holder is shown in Figure 1. The maximum dimension of the product is 98.30 mm x 70.00 mm x 68.40 mm, the average thickness of the plastic part is 2.00 mm, and the material of the plastic part is liquid crystal polymer LCP, T130 or T150, UL94-V0, shrinking The rate is 1.0035, the density is 1.7, and the mass of the plastic part is 42.17 grams. The technical requirements for 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.
It can be seen from Figure 1 that the plastic part is shaped as a complex shell formed by a regular planar rectangular structure. One side and one end surface respectively have a place to form the undercut of the mold. It is necessary to design the core pulling of the slider. The core pulling direction of the two sliders is shown in Figure 3. There is a circular arc surface at the bottom of the end slider, and the design needs to be reset here. The device enables the ejection system to reset first and then close the mold to avoid interference between the thimble at the bottom of the slider and the slider.
When the irradiation lamp holder is in use, the plastic parts need to withstand high temperatures. According to the performance requirements of the plastic parts, the plastic parts need to use LCP, and the fire rating is UL94-V0.
There are 12 fire protection classes in UL94: HB, V-0, V-1, V-2, 5VA, 5VB, VTM-0, VTM-1, VTM-2, HBF, HF1, HF2. Among them, HB, V-0, V-1, V-2, 5VA, 5VB are suitable for general hard plastics. The flame retardant grades of plastics increase gradually from HB, V-2, V-1 to V-0. V-0 is the highest requirement. The criterion is that the flame is extinguished within 30 seconds after two 10-second combustion tests are performed on the sample. No burning objects should fall. Judging whether there is a burning material falling, is based on whether it can ignite the medical absorbent cotton as the standard.
Liquid crystal polymer LCP has hot melt LCP and thermotropic LCP. Hot-melt LCP is mostly used for spinning. As an engineering plastic, thermally induced LCP is used. The appearance of the liquid crystal polymer is generally beige, and there are also white opaque solid powders with a density of 1.4 to 1.7 g/cm3. Liquid crystal polymer has the characteristics of high strength and high modulus. Because of its self-reinforcement, liquid crystal plastics that are not reinforced can reach or exceed the level of mechanical strength and modulus of ordinary engineering plastics reinforced with glass fibers; if Reinforced with glass fiber, carbon fiber, etc. far exceeds other engineering plastics. Liquid crystal polymers also have excellent thermal stability, heat resistance and chemical resistance. For most plastics, the creep defects of liquid crystal materials are negligible, and they have excellent wear resistance and anti-friction properties. The heat distortion temperature of LCP is 275～350℃, which is one of the highest heat distortion temperatures among thermoplastics. Liquid crystal plastics have high thermal stability, and LCP decomposes at 560°C in the air. It is solder-resistant and can be immersed in solder at 320°C for 5 minutes without change. The liquid crystal plastic has good weather resistance and radiation resistance, and has excellent flame retardancy. After the flame is extinguished, it will not continue to burn. Its flame retardant rating reaches UL94V-0 level. LCP is one of the special engineering plastics with the best fire safety. LCP also has excellent electrical insulation properties and outstanding corrosion resistance. The molding temperature of LCP is high. Because of its different varieties, the melting temperature is in the range of 300～425℃. LCP has low melt viscosity and good fluidity, similar to olefin plastics. LCP has a very small linear expansion coefficient and good dimensional stability.
LCP can be used in the electronic and electrical industry, and can be used to make office machinery, precision instruments, auto parts, etc. In addition, LCP has been used in microwave oven containers, this kind of stove must be resistant to high and low temperatures, LCP can fully meet the requirements. It can also be used for printed circuit boards, satellite electronic components, jet engine parts, plastic containers, sporting goods, films, fibers and medical supplies. New applications include: high-filled liquid crystal plastics can be used as integrated circuit packaging materials to replace epoxy resins as packaging materials for coil skeletons; as fiber optic cable joint sheaths and high-strength components; instead of ceramics for chemical separation towers Filling materials, etc. At present, the price of TLCP is still high, and it is mainly used in the electronics industry. The demand is small and the market is small. When it is used as an intensifier of polymer structural materials, the demand, the market and the output are large, and its cost and price will follow. The benefits brought by decline will be immeasurable, which is the potential of TLCP and its alloy applications. Although there are almost no TLCP products in our country, and some are only in the research and test stage, the above-mentioned potential and international trends urge us to keep up with the pace of international TLCP alloy research and development. It is expected that in the near future, with the development of my country's economic construction, it is believed that the country will also break through the difficulties and realize localization.
LCP has good processing performance, and the commonly used molding processing conditions are shown in Table 1.
