When using an injection molding machine, possible failures of hydraulic system of injection molding machine are diverse. It is result of a combination of many factors, dispersion is relatively large. Therefore, when performing fault diagnosis, it is necessary to analyze factors that cause fault one by one, pay attention to their internal connections, find out main contradictions, so that they can be resolved relatively easily.
Product diagram of double-threaded nut is shown in Figure 1. Maximum size of product is 29.00 mm * 29.00 mm * 32.00 mm, average thickness of plastic part is 5.15 mm, material of plastic part is PP, shrinkage rate is 1.018, and weight of plastic part is 11.20 grams. Technical requirements for plastic parts are that there must be no defects such as peaks, underfilling of injection molding, flow lines, pores, warpage deformation, silver streaks, cold materials, jet lines, etc. In addition to dimensional tolerances, plastic parts also need to ensure dimensional accuracy of their triangular threads to meet assembly requirements.
One of the biggest challenges in molding process of thick-walled plastic products is problem of dimensional accuracy. In this project, plastic hook (Figure 1) warped during the first mold trial; even if process parameters were adjusted, warpage still existed.
【Abstract】Latent glue feeding is a commonly used method of glue feeding in injection moulds. Design method and precautions of latent glue feeding are discussed, as well as problem and solutions of dragging powder that may occur after latent glue feeding.
As we all know, engine operating conditions are complex and harsh, need to adapt to various external environments, so there are generally higher requirements for engine parts. Especially in terms of resin materials related to engines, because of their high requirements for working temperature and pressure, it is necessary to use resin materials with superior performance.
【Abstract】Analyzed injection model and structure of injection mold of plastic bowl, designed cooling system by using Tian-shaped and s-shaped cooling water channels; compared two cooling schemes, analyzed temperature field distribution of plastic bowl, surface and internal temperature field of steel mold block after cooling for 10 minutes, S-shaped cooling scheme is better than Tian-shaped cooling scheme. In order to achieve a better cooling effect, an optimization model is proposed. Analyze pipe flow and heat transfer equations to obtain cooling influence factors, use optimization model to analyze temperature field distribution and verify that hydraulic flow rate, pipe material, and surface roughness play a decisive role in cooling.
Degradation: In process of processing, polymers are subject to high temperature, strong shearing force, etc. Under these strong effects, polymer chain will be broken and molecular weight will decrease, which is degradation.
With people's pursuit of high-quality life, thin-walled plastic parts are increasingly used in people's daily life. Thin-wall injection molding is not much different from traditional injection molding of plastic parts, except that there are some unique features in design of plastic parts and mold design, which require special attention from practitioners.
Abstract Combining structural characteristics of an automobile interior trim gusset, a simplified three-plate injection mold is designed. Mold adopts a point gate + side gate compound gating system to improve filling performance of melt, a delay slider mechanism is designed to prevent side surface from being damaged when plastic part is demolded. Mold has been verified by production: molded plastic part meets design requirements, which has a certain reference effect on molding of similar plastic parts.
【Abstract】Process requirements of threaded plastic parts of medicine bottle cap were analyzed, design scheme of thread withdrawal structure of medicine bottle cap injection mold was determined. Mold opening sequence, thread withdrawal structure, forming thread, alignment, and brace gear rack thread withdrawal structure design are discussed, thread brace positioning method and precautions are explained.