5 necessary conditions for excessive displacement of electric ball valve. The electric ball valve is mainly composed of expansion pipe, body, pressure plate, pressure plate bolt, limit bolt and packing. It is mainly used in thermal pipeline, and the size change of compensation pipeline caused by thermal expansion and cold contraction.
The sealing material of electric ball valve is generally packing, which is made of asbestos packing and graphite packing. This sealing material has a certain temperature resistance and lubricity, and can withstand the temperature of the medium. At the same time, the electric ball valve lubricates the expansion pipe under the working state, so that the expansion pipe can expand freely; Asbestos packing is used in pipes with hot water as the medium, and the temperature is below 100 ℃; Graphite packing is used in pipes with steam as the medium, and the temperature is below 200 ℃; When the temperature is higher, the sealing material is high temperature and high pressure resistant graphite ring, and the temperature is below 300 ℃. At the same time, the expansion tube is also chrome plated; Other materials: Q235 carbon steel.
Description of electric ball valve: 1. The electric ball valve provides great convenience for the installation and replacement of various water supply and drainage pipelines, water towers, pumps, water meters and valves, and plays a good role in regulating the expansion and contraction of long-distance pipelines due to temperature differences. 2. The inner pipe of electric ball valve is made of cast iron (HT), galvanized (DX) and steel (SF). The working pressure is divided into PN6, PN10 and PN16. 3. Before installing the electric ball valve, loosen the pressure plate bolt, pull the product to the installation length, and then tighten it with the diagonal method. Do not press it off. If it is used overhead, install corresponding fixing brackets at both ends. 4. GB4216.3-4126.5 standard shall be adopted for flange connection. 5. Electric ball valves of other specifications can be produced separately. When the electric ball valve is used, the expansion pipe flange and body flange are connected with the connecting pieces at both ends, and the pressure plate presses the sealing material, so that the sealing material is forced to play a sealing role; The expansion pipe can be freely expanded within the allowable expansion amount. Once the electric ball valve exceeds the displacement limit, the double nuts on the bolts lock the expansion amount to limit the position.