Special-shape parts

Plastic preforms, duroplastic components Brick and specially shaped parts Varied application as research tool Tablets and suppositories... 

The company has developed several series of products, such as super-thermal insulation flexible felts, thermal insulation panels, thermal insulation cylinders and special-shaped parts, translucent thermal insulation panels, siUca aerogel powders and particles. These products can be widely applied in aerospace and aeronautics, metallurgy, chemical plant installations, oil pipes, refrigerators, cars, ships, buildings, etc. 

Cylinders and Special-Shaped Parts for Thermal Insulation (CS)... 

Figure 40.8. Thermal insulation special-shaped parts.

CS Thermal insulation cylinders and special-shaped parts... 

The crystals obtained at 800°C have a square pillar form and almost all of them are hollowed in the central part of the cross section. At 1100°C the formation of specially shaped deposits is observed along with the growth of dendritic crystals of CoB (about 5 mm in length). 

In parts which are exposed to great heat, spans of more than 15 inches should he covered by arches. These are built up in the form of a segment of a circle, which should have sufficient spring to be stable. Although in former times it was usual for the bricksetter to cut his ordinary bricks into suitable shape for the arch, it is better to order specially shaped bricks for that kind of work. It may be laid down as a general rule, that in designing a furnace or other brick apparatus every detail should be worked out in such a manner that no cutting of bricks by the bricksetter is required. Bricks may be obtained from the makers of almost any size and shape, and in such intermediate sizes as will represent a brick cut into half... 

If the hemispherical dished head is not feasible, the ellipsoidal dished should be preferred over the torispherical dished head for tall vertical vessels, since the cost of the top closure is only a small part of the total cost of the vessel. For a battery of horizontal storage tanks or small vertical vessels, the torispherical dished head may be the more economical choice. Closures with conical, tori-conical, flanged and dished (not ASME) or flat shapes have no place in the design of tall vertical towers unless the process requires such special shapes for some particular reason. 

One of the recommended test methods for the determination of friction sensitivity was also developed by the German BAM [38]. If the substance to be tested is a solid, drying and sieving is recommended. This increases the sample s sensitivity to an extent, diich most probably exceeds the same under process condition. For the test the sieve fiaction is used which has passed the 0,0005 m mesh. Approximately 10 mm are spread over 0,1 m on a specific part of a porcelain plate. A specially shaped porcelain peg, which is fixed to a loading arm, is once moved forward and back over the sample, thus exerting a mechanical stimulus. 

Corona discharge is performed in a high-frequency alternating field (14-40 kHz) at 10 20 kV between two electrodes. The plastic surface is oxidized in a very short period (milliseconds). Plasma treatment is carried out under a moderate vacuum down to ca. 10 Pa. The advantage of this technique is the better penetration depth and the fact that it is also possible to treat shaped parts more easily. The plasma can also burn in gases (e.g., argon), whereby special effects (e.g., plasma polymerization) can be achieved. 

Rapid prototyping through stereolithography (STL) or other processes needs special shape information in the form of layers. The boundary of the shape of the part is processed by special methods, such as approximation by triangles. Control equipment for rapid prototyping receives geometry in standard STL format. The part model is translated into STL. All geometric... 

Aluminum is the metal of choice for metal reactors. It has excellent thermal and electrical conductivity and it is not readily attacked by any plasma except the heavy halogens (Cl, Br, I). It has been fabricated into cylindrical reactors (known as barrel reactors) and into rectangular reactors with shelf or cage electrodes. It is also possible to make special shaped electrodes for special applications. The only size limitations on metal reactors is the practicality of fabricating large vacuum vessels. The largest reactor that we have made is about one meter diameter by two meters deep. This is used to process automobile parts. 

With molded products, the stakes are usually molded into the part and then formed either by a hot tool or by ultrasonic staking with equipment similar to that used in ultrasonic welding. Often the tool has a specially shaped head that distributes the molten plastic in a uniform circle. 

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