How to produce shell products with no melting marks, no flow marks, no streamlines, no sink marks, and high surface gloss is particularly important for flat panel TVs, computer LCD monitors, air conditioners, and automotive interior parts. Using high gloss injection molding technology can solve this problem well. The principle of high-light injection molding is: The mold is heated before the mold is closed and the mold is closed. After the mold is closed, the temperature reaches the set condition and injection is performed. During the injection process, the mold continues to maintain a high temperature, so that the glue can maintain good fluidity in the mold during injection. After the injection is completed, the temperature of the mold is cooled when the pressure is maintained, and the cooling time of the product can be greatly shortened, thereby improving the production efficiency. Steam-free high-gloss injection molding technology currently belongs to an advanced production process in China. As this technology greatly improves the surface quality and surface strength of the products, it can eliminate the subsequent spraying or painting processes, protects the environment and the human health of the operators, and reduces the cost of the process due to the reduction of the process flow. Processing costs save energy and materials while significantly reducing production costs. The traditional method is to use a mold temperature machine to warm the mold, but the shortcomings of this method are as follows: 1) Unable to meet the need for rapid temperature increase and rapid temperature reduction in high-gloss injection molding; 2) The heating rate is small, and the weld marks on the surface of the product can only be reduced and cannot be eliminated; 3) The higher the hardness of the plastic, the worse the flowability. Therefore, the hardness of the surface of such products can only reach the HB level and can not meet the actual needs; 4) When the mold is heated up, it will expand by heat, and when it cools down, it will shrink, making the clamping force very unstable. It is likely to cause various defects such as dissatisfaction with the product, scorching, and high internal stress. The steam high-light injection molding technology developed on the basis of this process has been improved for the above defects: 1) This technology uses water in the mold to open the water pipe. It needs to pass steam when it is warmed up, it needs cold water when the temperature is reduced, and it uses compressed air to blow out the residual water after cooling to ensure that it can achieve rapid temperature increase and temperature reduction. 2) to eliminate the failure of various products, such as weld clips and water-lacking glues, to the greatest extent; 3) Due to the large increase in temperature, the use of H or even 2H hardness of the plastic, so that the surface of the product greatly increased the hardness; 4) As the pipeline is opened inside the mold, only the inner surface of the mold is heated or cooled, and the overall expansion of the mold is small, thereby reducing various product defects caused by the instability of the clamping force. To produce high-quality high-gloss products, injection molding machines, molds, special-purpose plastics for high-temperature products for temperature control equipment, and boilers and cooling devices are required. 1. The configuration of the press 1) The rigidity of the clamping mechanism is better; due to the constant heating and cooling during the entire production process. Therefore, the clamping mechanism of the injection molding machine must be rigid and strong enough to ensure the accuracy and stability of the clamping force. To ensure the surface quality of products. 2) The use of a large mold-clamping injection molding machine: Due to the inability to use gas-assisted injection when using this process, the clamping force required to produce the product will be relatively large. 3) Select a smaller amount of glue according to the situation: For example, when producing flat-panel TVs, LCD frames, and other products, do not need a large amount of plastic injection. When choosing an injection molding machine, try to select a small injection molding machine. The actual weight of the product is between 30% and 80% of the theoretical injection volume of the injection molding machine. If the amount of glue injected by the machine is too large, the plastic material can easily decompose in the cylinder for a long time, and the surface of the product will have defects such as silver wire. 4) The hardness of the plastic used for producing high-gloss products with special screws is relatively high, and its melt index is relatively low. Therefore, it is required that the plasticization of the screw is better. At the same time, the shear of the screw can not be too large, otherwise the rubber can easily decompose. 2. Mold configuration 1) The inner surface of the mold requires a very high finish to ensure the surface quality of the product; 2) The pipeline inside the mould must be reasonable to ensure rapid temperature rise and cooling; 3) The internal piping of the mold should have good thermal conductivity; 4) Due to the need for continuous heating and cooling in the production process, the steel used in the mold is better; 5) Pay special attention to the maintenance of the mold in the process of use to ensure that it is dry and dust-free. 3. Configuration of temperature control equipment 1) The temperature control must be very accurate. This is an important guarantee for the quality of the product; 2) The temperature control equipment reacts very quickly to ensure high production efficiency. Special plastic When producing products with higher surface quality, commonly used plastics are ABS, PC+ABS, or PMMA+ABS. Among them, ABS has the lowest hardness, and PMMA+ABS has the highest hardness, up to H and even 2H. However, the higher the hardness, the lower the melt index. The fluidity will be degraded, so suitable plastics can be selected according to production needs. With the increasing use of plastic parts and people's increasing awareness of environmental protection and safety, steam-free high-gloss injection molding has gradually become a frontier and popular technology in the field of future injection molding.
hydraulic block valve 100L/min
Max. Flow: 100L/min
Pressure: 310Bar
GKV100 series
GKV100 proportional valve is a stackable valve with interchangeable control styles.
Electro-Hydraulic pilot valves can be either 12 VDC or 24 VDC,corresponding current is 0-1.5 or 0-0.75Amp.
This series can provide following functions:
- Inlet module with pilot supply.
- Inlet module without pilot supply.
- A/B Port with overload valve on main section
- A Port with overload valve on main section
- B Port with overload valve on main section
- A/B Port with P.O. check
- A Port with P.O. check
- B Port with P.O. check
- End Cap with oil return function
- End Cap without oil return function
We can also choose other cartridges according to your requirement.
Valve Block,Standard Valve Block,Alloy Valve Block,Hydraulic Valve Block Hangzhou Hanray Industry Co., Ltd , https://www.aircompressor.pl
