Wuxi Xinming Automatic Control Valve Industry Co., Ltd. specializes in the production of various pneumatic valve accessories: pneumatic butterfly valves, pneumatic ball valves, pneumatic control valves, etc., and has been deeply involved in the industry for 13 years. For the selection of valves, Xinming Automation gives the following professional suggestions: When selecting valves, running, emitting, dripping and leaking are often related to pipe fittings and valves: 1. It is necessary to add bypass for pressure reducing valves, balance valves, etc.; 2. Ball valves and gate valves are suitable for full-open and full-close; 3. Use stop valves as little as possible; 4. Be careful when calculating the resistance of the valve; electric valves must be selected. Select the valve according to the on-off nature of the medium. The butterfly plate of the butterfly valve is installed in the diameter direction of the pipeline. In the cylindrical passage of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is between 0° and 90°. When the rotation reaches 90°, the valve is fully opened. The butterfly valve has a simple structure, small size, light weight, and only consists of a few parts. Moreover, it can be opened and closed quickly by rotating 90°, and the operation is simple. At the same time, the valve has outstanding fluid control characteristics. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is the resistance when the medium flows through the valve body, so the pressure drop that occurs through the valve is small, so it has better flow control characteristics. The butterfly valve has two sealing types: elastic seal and metal seal. Elastic sealing valve, the sealing ring can be embedded in the valve body or attached to the periphery of the butterfly plate. Valves with metal seals generally have a longer life than valves with elastic seals, but it is difficult to achieve a complete seal. The triple migraine butterfly valve developed now can achieve bubble-level sealing. The triple migraine butterfly valve is divided into composite layer sealing and all-metal sealing. The latter has high technical content and high processing cost, but the reliability and service life of the seal are much longer. In the fit layer, the butterfly valve is three-sided. Metal seals can get used to higher operating temperatures, while elastic seals have the disadvantage of being restricted by temperature. If the butterfly valve is required to be used as a flow control, the first thing is to correctly select the size and type of the valve. The structure principle of butterfly valve is especially suitable for making large-diameter valves. Butterfly valves are not only widely used in general industries such as petroleum, gas, chemical, and water treatment, but also used in cooling water systems in thermal power stations. Commonly used butterfly valves include wafer butterfly valves and flange butterfly valves. Wafer butterfly valves are connected between two pipeline flanges with stud bolts. Flanged butterfly valves are equipped with flanges on the valve. The flanges on both ends of the valve are connected to the pipeline flanges with bolts. The strength function of the valve refers to the ability of the valve to withstand the pressure of the medium. The valve is a mechanical product that bears internal pressure, so it is necessary to have satisfactory strength and rigidity to ensure long-term use without cracking or deformation. The ball valve evolved from the plug valve. It has the same lifting action by rotating 90 degrees, but the difference is that the cock body is a sphere with a circular through hole or channel passing through its axis. The share of the spherical surface and the channel opening should be such that when the ball rotates 90 degrees, it should show the spherical surface at the entrance and exit, and then block the activity. The ball valve can be closed tightly with only a 90-degree rotation and a small rolling torque. The completely equal internal cavity of the valve provides a straight flow channel with little resistance for the medium. It is generally considered that the ball valve is most suitable for direct opening and closing applications, but recent developments have designed the ball valve to save and control flow. The primary feature of the ball valve is its compact structure, easy to operate and repair, suitable for general operating media such as water, solvents, acids and natural gas, and also suitable for media with harsh operating conditions, such as oxygen, hydrogen peroxide, methane and ethylene. Ball valve The valve body can be integrated or combined. The stem axis of the globe valve is straight with the sealing surface of the valve seat. The valve stem has a relatively short opening or closing stroke, and has a very reliable blocking action, making this valve very suitable for media blocking or scheduling and economical use. Once the valve disc of the shut-off valve is in an open condition, there is no contact between its seat and the sealing surface of the valve disc, and it has a very reliable blocking action. This kind of valve is very suitable for media blocking or scheduling and saving use. Once the shut-off valve is in an open state, there is no contact between its seat and the sealing surface of the disc, so its sealing surface is less mechanically worn. Because most of the valve seats and discs are relatively simple to repair or replace It is not necessary to remove the entire valve from the pipeline when sealing the components, which is very suitable for the occasion where the valve and the pipeline are welded together. The movement direction of the medium passing through this type of valve has changed, so the movement resistance of the stop valve is higher than that of other valves. Commonly used shut-off valves are as follows: 1) Angle type shut-off valve; in the angle type shut-off valve, the fluid only needs to change the direction once, so that the pressure drop through this valve is smaller than that of the conventional structure. 2) Direct-flow stop valve; In direct-flow or Y-shaped stop valve, the flow passage of the valve body is in a diagonal line with the main flow passage, so that the damage degree of the activity condition is less than that of the conventional stop valve, so the pressure loss through the valve is corresponding Is too small. 3) Plunger type globe valve: The globe valve of this method is a variation of the conventional globe valve. In this valve, the disc and valve seat are usually designed based on the plunger principle. The valve clack is polished so that the plunger and the valve stem are connected, and the sealing is completed by two elastic sealing rings sleeved on the plunger. The two elastic sealing rings are separated by a collar, and the sealing ring around the plunger is pressed firmly by the load exerted on the bonnet by the bonnet nut. The elastic sealing ring can be replaced and can be made from a wide variety of materials. The valve is mainly used for "open" or "close", but a plunger or special collar with a special method can also be used to schedule flow.