How to choose Rising Stem Gate Valve and Non-rising Stem Gate Valve?

Common non-rising stem gate valves and rising stem gate valves have some common points, namely: (1) the gate valve is sealed by the valve seat and contact; (2) the gate valve of the gate valve Yes, the direction of motion is related to the direction of the fluid. Vertical (3) gate valves can only be fully opened and fully closed, and cannot be adjusted or throttled. So, what is between them? Gate valve manufacturers answer the gate valve and rising stem gate valve. The open stem gate valve rotates the handwheel, and through the advance and retreat of the handwheel, the valve plate connected to it is lifted and lowered to achieve the function. 

Gate valve is also called rotary stem gate valve (also called wedge gate valve). The nut is put on it, and the rotation of the handwheel drives the rotation to raise it. Usually, the bottom end has a trapezoid. Through the guide grooves on the bottom of the valve and the valve disc, the rotary motion becomes linear motion, that is, the operating torque becomes the operating thrust. 

Gate valve and rising stem gate valve: 

1.The exposure of the rising stem gate valve can be seen, while the gate valve is in the valve body and cannot be seen; 

2. The open gate valve is driven by the steering wheel, thereby driving the lift; the gate valve passes through the fixed point The rotation drives the lift. When switching, the steering wheel and valve stem are connected together and remain relatively stationary. 

3. The transmission of the gate valve is located in the valve body. During the valve process, it only rotates in situ, and the state of the valve cannot be judged by the naked eye; it is exposed to the outside of the valve body, and the opening and closing and position can be judged intuitively; 

4. The height of the gate valve is small, and the installation space is relatively small; the open gate valve is fully open 

5. The rising stem gate valve is outside the valve body, which is conducive to maintenance and lubrication; the gate valve is inside the valve body, which is difficult to maintain and lubricate, and is easily eroded by the medium and easily damaged. In terms of use, the rising stem gate valve is more extensive. 

The structure of gate valve and rising stem gate valve can be divided into: 

1.Lifting stem gate valve: the nut is on the bonnet or bracket. When the gate is opened, turn the nut to realize the lifting and lowering. This structure is beneficial to the lubrication, the degree is obvious, so it is widely used. 

2.Gate valve: The nut is in the valve body and is in direct contact with the medium. The gate is achieved by turning. The advantage of this structure is that the height of the gate valve remains unchanged, so the installation space is small, and it is suitable for gate valves with large diameter or limited installation space. This structure shall be fitted with indicators to indicate the extent. The disadvantage of this structure is that not only can it not be lubricated, but it is also directly eroded by the medium and is easily damaged. 

The above is the main difference between the two. When we choose to use it, we can choose it according to our immediate needs, rather than simply using it directly. Because the functions of the two are not completely the same, there are differences in many places, and we need to make a careful distinction.