Thermoplastic materials flow when they are heated to the proper temperature (which varies with each plastic). This ability can be verified by test, using a melt index unit per ASTM Test #D-1238. This ability to flow also determines how far a plastic can be injected through a specific wall thickness of a product. If the …
Tooling costs are extremely hard to estimate because of the variety of designs and steel types available. Tools can range from a thousand dollars to many hundreds of thousands of dollars depending on these factors, as well as the size of the part being molded and how many cavities are being molded at one time …
A parting line can be defined as any part of the mold that parts, and forms part of the part. There is usually only a single parting line, but there can be two or three or more, depending on the complexity of the mold. Items that determine the number of parting lines include: the geometry …
A mold is constructed using a series of components including various plates, pins, bushings, pillars, ejector systems, and many other items used for many purposes. Figure 1 shows some of the basic items and where they are located in the mold. Figure 1 shows the mold in the closed position. When the mold is open …
“Auxiliary Equipment” is considered any additional equipment required for assisting the primary equipment (molding machine) in producing the final production of the molded parts. It includes items such as granulators, mold temperature controllers, hopper loaders, and the like. These should not be confused with “Secondary Equipment” which is considered …
Plastic Mold Building Tips I’m sure you’ll agree with me when I say: Building a perfect plastic mold is really complicated. Or, is it? Well, it turns out that finish this job may not be as hard as you’d have thought. All you have do is to check the following 22 building tips and follow …
Any successful method of controlling the quality and the cost of a product depends heavily on the consistency of the process used to manufacture that product. Consistency can only be achieved by tightly controlling as many parameters as possible used during the manufacturing process. The environment on injection molding The environment …
Hot-runner molds offer significant processing advantages. Of primary importance is the material savings that results from elimination of the runner system. A hot-runner system represents in essence an extension of the machine nozzle through which the plastics melt flows directly into the cavities. For parts having identical weights, the amount of material to be plasticized …
Sprues，runners and gates fulfill the function of conveying the plastics melt from the nozzle of the injection unit to the individual cavities. While it is true that they may be reused in the form of regrind, their presence nevertheless means a reduction in the performance of the injection molding machine inasmuch as they must be …
Plastic Mould Ejection Injection moulding compounds exhibit a certain amount of shrinkage，i.e., in a cooled condition, the volume is somewhat smaller than in a heated condition. If parts with accurate dimensions are needed, allowances must be made for this shrinkage when establishing the dimensions of the cavities. Shrinkage also causes the molded parts to sit …