The material, called thermal expanded graphite, is used in production of flange seals. It is an analogue of generally known material graphlex. However the technology of making products of the thermal expanded graphite makes it possible to reduce production costs and improve the quality of final product.
Thermal expanded graphite is the material of new generation.
It possesses all the qualities of graphite, such as heat and chemical resistance, and low coefficient of friction. Besides, the thermal expanded graphite has an absolutely new quality–flexibility. This property is intrinsic during the whole service life despite high temperature, heat cycling and time.
The seals made of the thermal expanded graphite are high-reliable; they do not require special maintenance. In the course of time asbestos loses its flexibility, mass and volume, it is needed to be tightened unlike the graphite. Fluoroplastic does not endure high temperature and pressure, but the graphite goes on working at the temperature 560ВєC and pressure 400 atmospheres. Carbon packing also endures high temperature, but it is permeable for gases and fluids. However the graphite is absolutely impermeable at density 1 g/cm3. It is meant for operating in acids, alkalis, oil and potable water, that is why it is unnecessary to keep different packings and seals in store. Sliding work resource of the asbestos is 600 m, work resource of the graphite is 10.000 m. Graphite is very soft, that is why it has minimal influence on the gate-valve stem and pump shaft. Graphite and metal-graphite flange seals are used for sealing armature, pipelines, heat exchangers, compressors, pressure vessels, pumps and other technological equipment. The seals have a higher working resource, absolute ecological compatibility and ageing-resistance. The operating is possible in aggressive mediums at higher temperature.
Gland graphite seals are applied in gland end connections, mainly with rotary motion of a shaft, as well as out-worn flanges. The gland graphite seals have a higher working resource, absolute ecological compatibility and ageing-resistance. The operating is possible in aggressive mediums at higher temperature.
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