Flange connection Valve

Flange connected valve, its installation and disassembly are relatively convenient, but the flange connection than the threaded valve bulky, the corresponding price is high, so it is suitable for various sizes and pressure of the pipeline connection. When the temperature exceeds 350 degrees, due to the bolt, gasket and flange A change of slack, also significantly reduce the load of bolts, the force of a large flange connection may produce leakage.

Threaded Connection Valves

Threaded valve is mainly the nominal diameter of the valve below 50mm. If the size of the diameter is too large, the installation and sealing of the connecting part is very difficult. Threaded connections are usually made by turning the valve in and out of the end into a cone or straight pipe thread, which can be connected to a tapered pipe threaded joint or pipe path. Because the connection may have a larger leakage channel, sealing agents, sealing tapes or fillers can be used to plug these channels. If the material of the valve body can be welded, but the coefficient of expansion is very different, or the variation range of operating temperature is larger, the thread connection department must carry on the Honey seal welding. In order to facilitate the installation and removal of threaded connected valves, a fitting is available in the appropriate position of the piping system. Valves with nominal diameter below 50mm can be used as a fitting, and the thread of the pipe sleeve section will connect the two parts together.

Welded connection Valve

In the larger nominal diameter, the use of conditions, high temperature occasions, the valve body is often used for welding groove, at the same time, the welding seam has the original requirements, must choose a skilled welder to complete this work. Welded valves with nominal diameter below 50mm usually have welded sockets to undertake Hopping-side piping. As the socket welding between the socket and the pipeline to form a gap, it is possible to make the gap by some media corrosion, while the vibration of the pipeline will make the connection site fatigue, so the use of socket welding is limited. The welding connection is suitable for all kinds of pressure and temperature, and is more reliable than the flange connection when used under the condition of load-engraved. However, the welding connection of the valve disassembly and reinstallation are difficult, so its use is limited to the usual long-term reliable operation, or the use of conditional loading, high temperature occasions. such as thermal power plants, nuclear power engineering, Ethylene Engineering pipeline.