Cast pressing

As it flows through a narrow channel, the material is intensively intermixed, is additionally heated up due to friction by 20-30 C on average. In this case the hardening of the material takes place to a greater depth and is more uniform than in the case of direct pressing. The articles obtained are notable for a greater homogeneity of their properties. 

A review is given in Ref. [37] on the principles of the pressing and transfer molding technology of profile articles from compositions based on amino-, pheno- and epoxy resins. The designs of the press-molds in use and the technological equipment of commercial processes are described. 

A significant increase in labour productivity as against pressing can be attained in the processing of aminoplasts in the casting machines. 

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For direct comparison of explosives, it is frequently convenient to select pj-=1.0g/cc. While the actual vel of a given chge may be measured with present methods with an accuracy of ca 0.1%, the D(pj) curve is seldom known this accurately, owing to fluctuations in density of the chge and exptl error in the evaluation of p. In cast, pressed and liquid expls, it is possible to determine density very accurately, but in loose, granular chges an accuracy better than 2.0% is seldom attained. For this reason the literature frequently shows discrepancies of this magnitude in D pj° and M factor of eq 3.1. Table 3.1... 

Expl charges made of more than one expl, in which the contour of the boundary is an important design parameter, often are fabricated from cast, pressed, or machined components that are cemented together... 

From the solutions of polyimides in tetrahydrofuran (THF) strong, flexible and colourless films can be cast. Pressing of the polyimides carried out at temperatures 100 °C higher than Tg and 10 MPa leads to the formation of yellowish transparent moulded articles. 

Most military explosives are solid compounds which are manufactured in granular form, with bulk densities of less than 1 g cm-3. These granular compounds are then mixed with other explosive or inert additives to give explosive compositions with densities between 1.5 and 1.7 g cm 3. The explosive compositions are then cast, pressed or extruded into their final form. 

AN is also an ingredient in slurry type explosives, which are mixtures of AN, dynamite (TNT), water and aluminum. They are available as gels or with the consistency of thick soup. They can be used in open pit and underground mines as well as water-filled bore holes. Amatol explosives - mixtures of AN and TNT - have low sensitivity, and can be cast, pressed or granulated -depending on the ratios of the ingredients240. 

Approximately 0.5 pound of explosive is loaded in the same manner as it is loaded for actual use that is, cast, pressed, or liquid in a 3-inch pipe nipple (2-inch inside diameter, 1/16-inch wall) closed on each end by a cap. The loaded item, in the standard test, contains a small air space which can, if desired, be filled by inserting a way plug. The loaded item is subjected to the impact of caliber 30 bullet fired perpendicularly to the long axis of the pipe nipple from a distance of 90 feet. 

The grain size or the distinction cast/pressed have only been respected in individual cases, although they may often be very important. 

For the manufacture of large articles proposed a variant of gateless molding has been proposed. A new method of casting-pressing (casting into a semiclosed mold with the subsequent molding) is discussed in Ref. [44]. 

Reitsma examined different factors influencing the test, for example higlier humidity favours the exudation. Tlie test is not only influenced by impurities of TNT but also by the crystal size of the cast. Pressed cylinders of TNT do not show the exudation. 

Refractory oxides are an important class of materials that enable processes to exploit extreme environments. A wide variety of unary, binary, and ternary oxides can be considered refractory, based on their melting temperatures. Refractory oxides are generally prepared from powdered precursors using standard ceramic forming techniques such as casting, pressing, or extrusion, and subsequently sintered to achieve final density. In addition to chemical compatibility, the physical properties of refractory oxides such as thermal expansion coefficient, thermal conductivity, modulus of elasticity, and heat capacity must be considered when selecting an oxide for a specific application. 

Rolling, casting, pressing, spin casting, press-and-blow method, drawing are possible... 

PMMA films containing various amounts of the graft oopolynr r were prepared by heat pressing or solvent casting. Pressed films were prepared by heating at 150 C between Mylar films. Cast films were prepared from benzene solution onto clean glass slides. 

Some 80 percent of the electricity used by industry is apphed for electric drives which are elements of electromechanical systems. These systems are used to form (extrude, roll, cast, press, and spin), shape (mill, ream, drill, hone, and tap), and transport (conveyors, elevators, brakes, fans, pumps, and compressors). The remaining 20 percent of industry s electrical use is applied for electrolytic processes, process heating, lighting, and comfort conditioning. 

The device consists of the following main components two casting/pressing stations, automatic continuous lowering of the mould during Ailing, automatic strand cutting fixture, and instrumentation and control. 

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