How to control the oil special pipe? Let's briefly understand:Valves are used to open and close mechanical devices that may regulate the flow of media in a pipe. There are many types of valves and there are many ways to classify them. If it is distinguished by use, it can be divided into cut-off valve, check valve, dispatch valve, etc.; if it is divided by pressure, it can be divided into vacuum valve (working pressure is less than standard atmospheric pressure), low pressure valve (PN≤1.6MPa), medium pressure valve (PN) =2.5-6.4MPa) and high pressure valve (PN=10-80MPa). If the driving method can be divided into manual valve, power driven valve and automatic valve, there are still classification methods according to the difference of temperature or raw materials. The gate valve is equal to the valve base and the valve plate. The valve plate moves vertically up and down with the valve stem through the hand wheel, thereby cutting or dredging the pipeline, and at the same time adjusting the dredging ratio of the pipeline. Due to the characteristics of the ram, when used normally, the gate valve is mostly fully open or fully closed, which is less used for flow adjustment, but the gate valve has the advantages of good sealing function and easy maintenance. The valve core of the stop valve falls vertically on the base, the valve seat is parallel to the center line of the pipeline, the fluid flows in the "S" shape in the valve body, and the fluid resistance is large. The stop valve is usually used for flow adjustment, and has simple manufacturing and maintenance. A little bit, but it is easy to leak when closed, and the sealing is not as good as the gate valve.