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Of course this is not our home use ordinary switch tube to use, as the industry is called a gate valve. Opening and closing a gate valve is ram, the movement direction of the ram, perpendicular to the direction of flow of gate valve gate, as a straight line with the stem. In the lifting lever on the trapezoidal thread, through the valve at the top of the nut and guide groove on the valve body, turning the rotation movement into linear motion.

Full of flowing liquid pipeline, the gate valve pressure is very big. And the more turns will be the province of his strength, therefore when the design in order to save energy, usually with worm gear and worm transmission of the movement.

So if the valve has 100 scale, may need to turn 80 laps can we promote a scale. Usually gate valve is generally controlled by the electric, usually done normally it only takes a few minutes.

However, in some special cases, only by artificial to close the valve. Therefore seem to be much more demanding, so this is not original movie exaggerated, but has scientific basis.