Seals, Bridgeman

Figure 2.1-2 Different seal designs (a) 0-ring (b) soft gasket (c) unsupported-area seal (Bridgeman seal).

Figure 4.1-5 Modified Bridgeman seal autoclave showing the temperature gradient crystal growth onto seed crystals [17]. The nutrient is held at a higher temperature than the seed crystals, thus leading to supersaturation conditions in the seed region. The transport is ill a...

Equipment. A typical commercial quartz-growing autoclave is Hlustrated in Figure 1. The material of constmction for use at 17 MPa (25,000 psi) and 400°C can be a low carbon steel, such as 4140, or various types of low aHoy steel. The closure, a modified Bridgeman closure, is based on the unsupported area principle (12). That is, the pressure in the vessel is transmitted through the plunger to the steel surfaces which initially are nearly line contacts. Thus, the pressure in the seal surface gready exceeds the pressure in the vessel because most of the area of the plunger is unsupported. Hydrothermal equipment has been further discussed (10). 

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