The valve is a control component in the fluid conveying system, which has the functions of cut-off, regulation, diversion, prevention of reverse flow, stabilization, diversion or overflow and pressure relief. Valves used in fluid control systems, ranging from the simplest shut-off valves to the various valves used in extremely complex automatic control systems, have a wide range of varieties and specifications.
Different piping systems use mechanical valves with different materials, structures, functions, and connection methods. Therefore, there are active branches and trickles inside the mechanical valves, which have their own advantages, disadvantages and application fields. The technicians need to choose mechanical valves according to the actual needs of the piping system. , To ensure the stable operation of the pipeline system.
The shut-off valve has a simple structure. It is very convenient and simple whether it is assembly, use, operation and maintenance, disassemble in the pipeline system, or production and quality inspection in the factory; the sealing effect is good, and the service life in the pipeline system is long This is because the disc and sealing surface of the shut-off valve are relatively static, and there is no wear caused by sliding; time-consuming and labor-intensive, this is because the disc stroke is short and the torque is large, and it takes more force and time to open the shut-off valve ; The fluid resistance is large, because the internal passage of the shut-off valve is more tortuous when facing the fluid, and the fluid needs to consume more power in the process of passing the valve; the fluid flow direction is single, and the current shut-off valve discs on the market can only support a single direction Move, do not support two-way and above direction changes.
The opening and closing of the gate valve is completed by the top nut and the gate. When closing, it relies on the internal medium pressure to realize the pressing of the gate and the valve seat. When opening, it relies on the nut to realize the lifting of the gate. Gate valves have good sealing and shut-off performance, and are usually used in piping systems with a diameter greater than 50 mm. The pressure is used to realize the pressing of the gate and the valve seat, and the nut is used to realize the lifting of the gate when it is opened. Gate valves have good sealing and cutting performance, and are usually used in pipeline systems with a diameter greater than 50 ㎜
Among. The throttling function is widely used in oil, natural gas, and water supply pipelines
The ball valve has the performance of adjusting the fluid flow direction and flow rate, and has high sealing performance. The sealing ring is mostly made of PTFE as the main material, which is corrosion resistant to a certain extent, but the resistance to high temperature is not high, exceeding the appropriate temperature range The aging is very rapid, and it will affect the sealing effect of the ball valve. Therefore, the ball valve is more suitable for two-position adjustment, less fluid resistance, higher requirements for tightness, and high temperature limits within a certain degree of piping system. The universality is low, and it is suitable for more system branches and more detailed operation requirements. Application in high pipelines is not necessary in straight pipelines, there is no need for fluid flow direction, flow volume, and fluid temperature is too high in a pipeline system, which will increase cost pressure.
The butterfly valve adopts a streamlined design as a whole, so the resistance from the fluid is relatively small when used in the pipeline system. The butterfly valve uses a through rod structure to operate the valve. The valve is closed and opened not by lifting, but by rotating, so the degree of wear is low and the service life is long. Butterfly valves are usually used in pipe systems for heating, gas, water, oil, acid and alkali liquid transportation. They are mechanical valves with higher sealing, longer service life, and less leakage.
Post time: Dec-24-2021