Design molds: blow, 203 compression

Part Design Blow Molding Casting Compression Extrusion Filament Winding Injection Matched Die Molding Rotational Thermo- forming Transfer Compression Wet lay-up (Contact Molding)... 

The final product may take any one of a vast multitude of final forms. These include, but are not limited to, construction materials, toys, automotive parts, kitchen aids, industrial parts, sports and recreational equipment, containers of all sizes and description, and an unlimited variety of packaging products for foods, drugs, cosmetics, and other consumer products. The processes that are used to produce or mold or fabricate the final products are also varied and depend on the design and purpose of the product. Some of these processes include extrusion, compression molding, roto-molding, blow molding, sheeting, and films. 

Part design Blow molding Casting Compression Extrusion Filament winding Injection Matched die molding Rotational Thermo- forming Transfer compression Wet lay-up (contact molding)... 

Design rules Blow Molding Casting Compression Molding Extrusion Injection Molding... 

In the continuous extrusion design process, the parison is continuously extruded between the open mold halves from an accumulator head. When the required length of parison has been produced, the mold is closed, trapping the parison that is severed usually by a hot knife from the die. Figure 6.7 provides a simplified schematic of a continuous BM process. Land or pinch-off areas on the mold compress and seal the upper and lower ends of the parison to make an elastic airtight part. Compressed air is introduced through the blow pin into the interior of the sealed parison that expands to take up the shape of the mold cavities. The cooled mold chills the blown object that can then be ejected when the mold opens. 

TPUs can be blow molded, and the requirements for the screw design are the same as for extrusion. Both injection molded and blow molded parts should be heated at 100 °C for 24 hours to reach the equihbrium structure and minimize creep and compression set. The main field of application of thermoplastic urethanes is for various casters, rollers, wheels, flexible clutches, seals and gaskets for hydraulic machines, shoe soles, printing rolls and machine parts. 

Boots are typically blow molded from thermoplastic elastomers, CVJ boots from TEEE (COPE) and TPV, and shock absorber boots from TPU(E) such as Desmopan. Thermoplastic etherester elastomers and thermoplastic esterester elastomers TEEE (COPE), Arnitel, and Hytrel are blow molded into transmission and wheel CVJ boots for front-wheel drive (FWD) and rack-and-pinion boots. CVJ boots keep grease inside the joints and keep out dirt, grease, salt, and water. The TEEE CVJ drive axle boots have a balance of flexibility and stiffness, fatigue resistance to compression and expansion strains, chemical resistance, and meet accordion design requirements between -40 to 212°F (-40 to 100°C). 3- ... 

The most commonly used of these techniques is extrusion blow molding, where the parison is a hollow, thick-wallcd tube of melt that is extruded vertically from a crosshead die. (A schematic diagram is shown in Fig. 19.39.) The parison then is surrounded by a split, cooled mold of the desired shape. One end of the parison is damped around a blow pin, which incorporates an inlet for compressed air that expands the parison to make it contact the mold wall. The molded object is ejected when solidified, and excess material is trimmed from the ends and recycled. Containers in the range of 0.25 to 5000 liters are made this way, and integral handles as well as special shapes can easily be designed in. 

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