Non-rising Stem Gate Valve

Non-rising stem gate valve is a type of valve, which is characterized by the gate as the opening and closing part, and the movement direction of the gate is perpendicular to the direction of the fluid. Unlike rising stem gate valve, the valve stem nut of non-rising stem gate valve is set on the gate, and the handwheel rotates to drive the valve stem to rotate, thereby lifting the gate. Usually there is a trapezoidal thread at the bottom of the valve stem. Through the thread at the bottom of the valve and the guide groove on the valve disc, the rotary motion is converted into linear motion, that is, the operating torque is converted into operating thrust. When opening the valve, when the gate lift height is equal to 1:1 times the valve diameter, the fluid passage is completely unobstructed, but this position cannot be monitored during operation. In actual use, the top of the valve stem is used as a mark, that is, the position that cannot be opened, as its fully open position. In order to consider the locking phenomenon caused by temperature changes, it is usually opened to the top position and then retracted 1/2~1 turn as the position of the fully open valve. Therefore, the fully open position of the valve is determined by the position of the gate (i.e. the stroke). Advantages of non-rising stem gate valves

Non-rising stem gate valves have the following significant advantages:

• Compact structure: Since the valve stem thread is located inside, the appearance of non-rising stem gate valves is more compact and suitable for occasions with limited space.
• Good protection: The valve stem thread is inside, which reduces the impact of the external environment on the valve and improves the protection level of the valve.
• Convenient maintenance: The maintenance of non-rising stem gate valves usually only requires the removal of the valve cover, and there is no need to remove the entire valve stem like the rising stem gate valve.
• Wide range of applications: Non-rising stem gate valves are suitable for a variety of media, including liquids, gases and steam.

Application of non-rising stem gate valves

Non-rising stem gate valves are widely used in various industrial fields, including water supply, drainage, petrochemical, electric power, metallurgy and other industries due to their compact structure, good protection and convenient maintenance