Cast extrusion processes

The OPS extrusion process is distinguished from conventional cast extrusion (unoriented) processes by the additional energy requirements of the MDO and TDO units. Cast extrusion processes generally require 0.2-0.7kWh per kilogram of extruded product. The OPS process requires 0.7-0.9 kW h per kilogram of extruded product, which increases conversion cost. 

Cast extrusion Processed meat, cheese, snacks, bakery PP/nylon/EVOH/nylon/LDPE... 

Melt Extrusion. By far the most important method for producing film and sheeting materials reties on one or another of the various melt extmsion techniques (5). The main variations of melt extmsion are the slot (or flat) die-cast film process, the blown films process, and the flat die sheeting-stack process. These may be combined with one or more steps such as coextmsion wherein multilayer film or sheet is formed, biaxial orientation, and in-line coating (6). 

As forming processes, slip casting, extrusion, isostatic pressing and electrophoretic forming have been applied. There are some advantages to isostatic pressing ... 

In the extrusion process, high pressures are applied to a cast billet of aluminum, forcing the metal to flow through a die orifice. The resulting product is an elongated shape or tube of uniform cross-sectional area. 

Polypropylene film is found in a variety of applications. Films are thin plastic sheets with thicknesses less than 250 pm. Applications for these films include candy mappers, plastic label material, electrical capacitors (which requires very pure polymer), and fiber glass insulation backing. There are two general categories of polypropylene films unoriented and oriented. Films are manufactured through either a cast or a blown film extrusion process. Oriented films exhibit improved strength relative to unoriented films. This means that they can be... 

History. The cast double-base process was developed under U.S. Government auspices during World War II, the initial work being done by Kincaid and Shuey (7). The process filled a need for rocket charges significantly larger than those conveniently made by the then existing extrusion processes. 

Cast film extrusion. In a cast film extrusion process, a thin film is extruded through a slit onto a chilled, highly polished, turning roll where it is quenched from one side. The speed of the roller controls the draw ratio and final film thickness. The film is then sent to a second roller for cooling of the other side. Finally, the film passes through a system of rollers and is wound onto a roll. A typical film casting process is depicted in Figs. 3.53... 

Figure 8-6. Schematic of cast film extrusion process (reprinted with permission from Tess and Poehlein, copyright 1985, American Chemical Society).

At its plant in Mont-de-Marsan, France, Autobar begins the production process by creating 330 micron film sheets from the NatureWorks PLA resin using a standard cast extrusion line. The extruded sheet is then thermoformed. 

The first step in the manufacture of a CMC component is the production of a net-shape or near-net-shape preform from either ceramic particles or ceramic fibers. Particulate preforms can be produced by any of the conventional ceramic processing routes, such as uniaxial or isostatic pressing, injection molding, sediment casting, extrusion, or slip casting. A... 

The cast film extrusion process is schematically shown in Figure... 

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