Three common defects in polyphenylene sulfide injection molding, how to prescribe right medicine

group on main chain of molecule. Polyphenylene sulfide has excellent heat resistance, long-term use temperature is 200 ℃; good chemical resistance, with excellent chemical properties similar to polytetrafluoroethylene; also has special rigidity, good compatibility with various fillers and other polymer materials. At present, it is the lowest price among high temperature resistant engineering plastics and can be molded by general thermoplastic processing methods.

Design of Injection Mold for Irradiation Lamp Frame

Product of irradiation lamp holder is shown in Figure 1. Maximum size of product is 98.30 mm * 70.00 mm * 68.40 mm, average thickness of plastic part is 2.00 mm. Material of plastic part is liquid crystal polymer LCP, T130 or T150, UL94-V0, shrinkage rate is 1.0035, density is 1.7, and weight of plastic part is 42.17 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.

Design points of injection mold positioning system

Problem of guiding and positioning is repeated staggered actions when injection mold is closed and opened. When closing mold, guide pin and guide sleeve are the first to guide, to ensure that mold parts have correct initial movement trajectory. After orientation is over, positioning comes into play. Due to different structure of plastic parts, each plastic part will have lateral force more or less during injection molding. Deep cavity plastic parts and asymmetric plastic parts have the largest lateral force. There is a gap between guide posts and guide sleeves, and its working state is actually line contact. Therefore, in injection mold, huge lateral force during injection cannot be withstood only by guide post and guide sleeve. Positioning system must be designed to withstand lateral force. Structure of injection mold to ensure that moving parts move according to established trajectory is called guiding system; structure to ensure relative position accuracy between front and rear molds, between movable parts is called positioning system. As an important part in mold production process, guide post is used for guiding, supporting and positioning. Support means that guide post needs to bear weight of mold plate.

Design of Injection Mould for 135° Elbow Pipe of Injection Molding Machine

Abstract A 2-cavity two-plate mold was designed for injection molding of plastic parts of 135° elbow pipe of injection molding machine. Mold uses 4 types of demolding mechanisms for demolding of molded plastic parts, including bend pipe, straight pipe, retractable, push rod ejection and other demoulding mechanisms. Elbow core pulling mechanism uses a rack to drive sector gear, then arc slider is driven to perform rotary core pulling; straight tube core pulling mechanism uses a hydraulic cylinder to drive inner and outer wall cores to perform 2 core pulling; inner core pulling mechanism uses T-slots locking block to drive inner retractable core pulling; plastic part is finally pushed out by push rod.

Heat treatment process of plastic mold parts

Different types of steel are used as plastic molds, their chemical composition and mechanical properties are different, so manufacturing process routes are different; similarly, different types of plastic mold steels use different heat treatment processes. This section mainly introduces manufacturing process route and characteristics of heat treatment process of plastic mold.

Hot runner injection mold design for paper holder

Paper holder is an important part of shell of a certain Japanese brand printer. Product picture is shown in Figure 1. Maximum size of product is 495.45 mm * 348.69 mm * 71.84 mm, average thickness of plastic part is 2.85 mm, material of plastic part is HI-PS, shrinkage rate is 1.005, weight of plastic part is 675.20 grams. Technical requirements of 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.

The only way to start injection molding machine!

Irregular start-up process of injection molding machine will cause quality degradation, poor mass production, short machine life, screw damage and many other conditions. Following article will give you a detailed and comprehensive introduction to start-up, teach you to standardize process and avoid boring.

10 classic bolt-proof designs!

Once bolt connection in mechanical equipment is loosened, it will cause bolt to fall off and cause major safety hazards, or bolt slack pre-tightening force will decrease, which will greatly shorten fatigue life of bolt connection. Therefore, appropriate anti-loose measures should be selected in design to ensure that bolts do not loosen in actual use.

Design of Injection Mould for Shell of Juicer

【Abstract】According to structural characteristics of juicer shell and technical requirements that outer surface does not allow contour marks of slider, a simplified three-plate mold base was selected, a gating system of "circular runner + sector gate", a fixed mold slider + an inclined top core pulling mechanism was designed on mold. Choosing a circular runner + … Continue reading Design of Injection Mould for Shell of Juicer

Quality standards for conventional injection molded parts

This standard mainly stipulates inspection and test methods for various plastic products produced by injection molding. It is suitable for inspection of general injection products. This standard is for routine testing only. Particular requirements are subject to PARTSPEC. 1. Explanation of common defects Scorch marks (RURNS): Material decomposition caused by heat.DISCOLORATION: Deviation from original color … Continue reading Quality standards for conventional injection molded parts