Introduction To Globe Valve

Globe valve is one of the most widely used block valves in chemical production. Compared with the above three block valves, it is not opened by rotating its closing member

To close the valve, the valve rod lifts and drives the connected round valve disc (valve head) to change the distance between the valve disc and the valve seat to control the opening and closing of the valve.

Streamline stop valve American standard stop valve

Features: the upper part of the globe valve is provided with handwheel and valve stem, the middle part is provided with thread and packing culvert sealing section, the thread on the small valve stem is in the valve body, and the structure is compact,

However, there are many contact parts between the valve rod and the medium, especially the thread part, which is easy to be corroded. The opening degree of the valve can be judged from the height of the valve rod exposed from the bonnet. In order to prevent the medium from leaking out along the valve rod,

Packing can be used at the position where the valve rod passes through the bonnet.

The globe valve has a complex structure, but it is easy to adjust the flow and cut off the channel, and it can be opened and closed slowly without water hammer. Therefore, it is widely used.

When installing the stop valve, pay attention to the direction of fluid. The pipeline fluid shall flow through the valve seat port from bottom to top. The so-called "low inlet and high outlet" is to reduce the fluid resistance,

The valve stem and the packing culvert shall not contact with the medium during opening and closing, so as to avoid damage and leakage of the valve stem and the packing culvert.

Globe valves are mainly used for pipelines of water, steam, compressed air and various materials. They can accurately regulate the flow and tightly cut off the channel, but they cannot be used for pipelines with high viscosity

Material easy to crystallize.

Precautions for use:

1. Check the valves for defects prior to opening, especially leakage from the stuffing box

2. When the valve rod cannot be directly rotated by hands, special F wrench can be used for opening and closing. When the valve rod still cannot be opened and closed, do not lengthen the wrench arm to forcibly open and close,

So as to cause damage to valves or safety accidents;

3. When the valve is used for MP steam pipeline, the condensate water in the pipeline shall be drained before opening, and then the valve shall be opened slowly to preheat the pipeline with 0.2-0.3Mpa steam,

Avoid damage to the sealing surface caused by sudden pressure rise, and adjust the pressure to the required state when it is normal;