Slide mold

Necessary demolding and ejection aids (for example, slide mold, split mold, etc.)... 

FIGURE 3.14 Slide mold made from ALUMOLD 1-500 for the production of a mudguard Left lower bottom... 

Urethanes are processed as mbber-like elastomers, cast systems, or thermoplastic elastomers. The elastomer form is mixed and processed on conventional mbber mills and internal mixers, and can be compression, transfer, or injection molded. The Hquid prepolymers are cast using automatic metered casting machines, and the thermoplastic peUets are processed like aU thermoplastic materials on traditional plastic equipment. The unique property of the urethanes is ultrahigh abrasion resistance in moderately high Shore A (75—95) durometers. In addition, tear, tensUe, and resistance to many oUs is very high. The main deficiencies of the urethanes are their resistance to heat over 100°C and that shear and sliding abrasion tend to make the polymers soft and gummy. 

Undercut Whether external or internal, undercuts should be avoided if possible to reduce mold cost (by about 25 to 30%) and simplify melt flow during molding. However many molds use external and/or internal undercuts. In cases where it is essential to incorporate them in a design, appropriate mold design is required. The mold will include action such as sliding components on tapered surfaces, split cavity cam actions to produce the needed undercut, etc. (Chapter 8, TOOLING)... 

We can further characterize polymers into thermoplastics and thermosets . Thermoplastics consist of linear or lightly branched chains that can slide past one another under the influence of temperature and pressure. These polymers flow at high temperatures which facilitates their molding into useful products. Thermosets consist of a network of interconnected chains whose positions are fixed relative to their neighbors. Such polymers do not flow when heated. 

The mixer was made by casting, molding and curing [25,93], Then, the channels were covered by glass slides. Two ports were placed at the inlet reservoir feeds. The liquids were pumped by hydrostatic pressure. Platinum electrodes were deposited in the upstream and downstream reservoirs by AC excitation. The EKI then occurs along the entire channel. 

Allow the gel to come to room temperature and then carefully slide the glass plate off of the mold. Wrap the gel tightly with plastic wrap. 

Film Preparation. Polymer films (10 mil thick) were prepared by compression molding for one half hour at 175 °C. between evaporated gold films on glass microscope slides or sheets of 0.7 mil aluminum foil (Reynolds Aluminum Wrap) which had been chemically etched as above. 

Closing the Mold. One half of the mold is attached firmly to the melting/feeding end of the injection molding machine. The other half slides horizontally to open or close the mold. The moving half is driven mechanically or hydraulically. When it closes the mold, it is held firmly by clamping action to withstand the injection pressure. 

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