For hardware plastic mold accessories with complex shapes, selecting suitable locating rings, sprue sleeves and other accessories is a process that requires comprehensive consideration of many factors.
The main function of the locating ring is to determine the relative position of the injection machine nozzle and the sprue sleeve. Generally, the locating ring is matched with the center locating hole of the injection machine fixed mold fixing plate, and the matching accuracy is usually H11/h11. For hardware plastic mold accessories with complex shapes, the size selection of the locating ring is particularly critical. Due to the complex shape of hardware plastic mold accessories, more precise positioning may be required during installation, so a locating ring with a high matching degree with the center locating hole of the injection machine fixed mold fixing plate should be selected. If the size of the locating ring is not appropriate, the hardware plastic mold accessories may be installed unstably on the injection machine, affecting the injection molding accuracy. In addition, there are also requirements for the matching length of the locating ring and the locating hole. Small hardware plastic mold accessories take 8-10mm, large hardware plastic mold accessories take 10-15mm, and complex hardware plastic mold accessories can be appropriately adjusted within this range according to actual conditions to ensure the stability of positioning.
The sprue bushing is an important part of the hardware plastic mold accessories pouring system, which is used to set the main channel. When selecting the sprue bushing, it is necessary to consider its matching method with the positioning ring. There are two common sprue bushings, A and B. The B-type sprue bushing is set to prevent the sprue bushing from exiting the fixed mold under the action of the melt back pressure. When using it, just use the positioning ring fixed on the fixed mold to press the large end step of the sprue bushing. For hardware plastic mold accessories with complex shapes, if the melt back pressure is large during the injection molding process, it is more appropriate to choose the B-type sprue bushing. In addition, the length of the sprue bushing should be consistent with the thickness of the matching part of the fixed mold, and the end face at the outlet of the main channel should not protrude on the parting surface, otherwise it will affect the mold closing and injection molding quality of the hardware plastic mold accessories.
In terms of material, both the positioning ring and the sprue bushing need to have good wear resistance and high temperature resistance. During the injection molding process, hardware plastic mold accessories will be subjected to high temperature and high pressure. If the material of the accessories is not wear-resistant, it is easy to wear, resulting in inaccurate positioning or poor sealing of the sprue bushing. Generally, specially treated steel can be selected. This kind of steel has high hardness and wear resistance and can maintain stable performance in high temperature environment.
Processing accuracy is also an important factor to consider when selecting accessories. Complex shape hardware plastic mold accessories require higher processing accuracy of accessories. The inner hole of the positioning ring and the outer diameter of the sprue bushing need to be precisely processed to ensure the matching accuracy between them. If the processing accuracy is not enough, it may cause gaps in the hardware plastic mold accessories during installation, affecting the injection molding accuracy and product quality. When selecting accessory suppliers, manufacturers with advanced processing equipment and exquisite processing technology should be selected to ensure the processing quality of accessories.
In addition, the versatility and interchangeability of accessories should also be considered. During the use of hardware plastic mold accessories, accessories may be damaged or need to be replaced. If the accessories have good versatility and interchangeability, it is easy to find substitutes, reducing maintenance time and cost. Therefore, when selecting positioning rings and sprue bushings, try to choose accessories that meet industry standards.
For complex shape hardware plastic mold accessories, customized positioning rings and sprue bushings can also be considered. Due to the special shape of hardware plastic mold accessories, standard accessories may not fully meet the needs. By cooperating with professional hardware plastic mold accessories manufacturers, we can customize suitable positioning rings and sprue bushings according to the specific shapes and injection molding requirements of hardware plastic mold accessories, so as to better ensure the performance and injection molding quality of hardware plastic mold accessories.
When selecting suitable positioning rings, sprue bushings and other accessories, it is necessary to comprehensively consider factors such as positioning accuracy, material, processing accuracy, versatility and interchangeability. For hardware plastic mold accessories with complex shapes, customized accessories can also be considered to ensure that hardware plastic mold accessories can operate normally and produce high-quality products.
