When closing a gate valve, excessive force should not be applied, mainly due to its structural characteristics, sealing principle, and long-term safety. This can be understood from the following aspects:

Prevent component damage

The sealing of gate valves mainly relies on the tight fit between the gate and the valve seat. If too much force is applied, it can cause excessive compression of the sealing surface between the gate and valve seat, which may result in deformation, scratches, or wear of the sealing surface, ultimately damaging the sealing performance and shortening the service life of the gate valve. In addition, transmission components such as valve stems and nuts may also experience bending, breakage, or thread slippage due to excessive torque, directly causing the gate valve to malfunction.

Prevent valve body deformation

The valve body, as the load-bearing component of the gate valve, may undergo slight deformation due to the sudden impact force generated when closing (especially for brittle materials such as cast iron gate valves). Although this deformation is difficult to detect with the naked eye, it can damage the precision of the internal structure, leading to difficulties in opening or sealing failure in the future.

Affects operational accuracy

The closing process of the gate valve needs to be accurately controlled, and excessive force may lead to "clearance" - that is, the gate exceeds the normal sealing position, which in turn affects the sealing effect. At the same time, excessive force can make it difficult for operators to determine whether the gate valve is truly in place, and long-term reliance on violent operation may also form a habit of misjudgment, increasing the risk of failure.

Protect the driving device

For automatically driven gate valves such as electric and pneumatic ones, excessive force (such as manually intervening with the electric device) can directly damage the drive motor, gearbox, and other components, leading to equipment failure and even causing safety hazards.

Therefore, when operating the gate valve, the principle of "smooth operation and moderate force" should be followed. Close it until there is a slight resistance, without excessive force, in order to effectively protect the various components of the gate valve and ensure its long-term stable operation.