1、 What is the principle of a shut-off valve?

A globe valve uses the torque of the valve stem to exert downward pressure on the sealing surface, relying on the pressure of the valve stem to tightly fit the sealing surface of the valve disc and the sealing surface of the valve seat, preventing the flow of medium or regulating the flow rate of medium.

2、 What is the scope of application of globe valves?

1. Suitable as a shut-off valve on thermal oil, toxic, flammable, highly permeable, environmentally polluting, and radioactive fluid medium pipelines, it can also be used for regulation and is a high-quality product for creating leak free factories. All castings of this valve are precision cast.

2. A globe valve refers to a valve whose disc moves along the centerline of the valve seat. According to the movement of the valve disc, the valve seat opening is directly proportional to the valve disc stroke. Due to the short stroke of the valve stem when opening or closing, and the reliable cut-off function, as well as the proportional relationship between the change of the valve seat opening and the stroke of the valve disc, this type of valve is very suitable for regulating flow as a cut-off or regulating and throttling function. Similarly, pneumatic ball valves are also suitable.

3、 What is the function of a shut-off valve?

1. The opening and closing components used in globe valves are plug shaped valve discs, which are divided into flat and conical surfaces on the sealing surface. The valve disc moves in a straight line along the centerline of the fluid. The movement forms of the valve stem include the lifting rod type (valve stem lifting, handwheel not lifting), as well as the lifting rotating rod type (handwheel and valve stem rotating together to lift, nut installed on the valve body).

2. The stem axis of the globe valve is perpendicular to the sealing surface of the valve seat. The medium flow direction of the shut-off valve changes from above the valve disc to enter the valve chamber. At this time, under the pressure of the medium, the force to close the valve is small, while the force to open the valve is large, and the valve stem opening or closing stroke is relatively short. Once the shut-off valve is in the open state, there is no contact between its seat and the sealing surface of the valve disc, so its sealing surface has less mechanical wear and a very reliable cutting action. Due to the fact that the seat and disc of most globe valves are relatively easy to repair or replace sealing components without the need to remove the entire instrument valve from the pipeline, this is very suitable for situations where instrument valves and pipelines are welded together.

3. In general, the function of a globe valve is only to fully open and fully close, that is, to cut off. However, some variations of globe valves can also achieve adjustment and throttling through structural changes.