stainless steel ball valve application
To say the king of vacuum valve, it is ball valve. Stainless steel ball valve has been used for a long time and is widely used. So far, it is still used in various countries, especially small caliber valve, which is still dominant in all kinds of valves. The utility model is characterized in that the pressure difference between the front and rear of the valve plate makes the valve plate forced to press on the valve seat on the right side of the outlet, which has good sealing performance and is used to cut off the medium in the pipeline when it is fully opened.
Stainless steel ball valve has been scoured by materials for a long time, resulting in serious impact wear, which can not meet the normal production and shorten the service life of the equipment. At present, wear-resistant materials, such as stainless steel valves, polymer composite materials and other methods are widely used for ball valve wear.
Polymer materials have superior adhesion performance, super wear resistance, pneumatic diaphragm pump to solve the problem of metal wear, to ensure the normal production of enterprise equipment. And the unique ceramic materials and special surface strengthening agents in the materials.
The disadvantage of ball valve is that the operating torque is large, and the valve body and valve stem are easy to be damaged during operation, especially the large diameter gate valve. The overall dimension and weight are also large. The diameter of the gate valve is about 3200 mm high, which requires four people to operate. Therefore, the gate valve is generally used in small diameter, i.e. below DN500. The flow resistance of stainless steel valve is small from full opening to middle opening, and increases rapidly when it is close to full closing. In a larger range, the flow resistance changes little. When the valve is close to full closing, the flow rate changes greatly. It must not be used when the valve is close to closing, so it is difficult to fine tune the flow. If the valve opening is very small and the flow velocity at the opening is extremely fast, cavitation will occur at the lower side of the gate, accompanied by intense vibration and noise. If the valve is operated for a long time, cavitation will occur on the metal of the valve body and the gate.