Register Forgot password?
Brief introduction of the principle of the globe valve
Source: | Author:Xinsy WZ | Publish time: 386 days ago | 395 Views | Share:
How the globe valve works?Globe valve is only works for full open and full close by pressure forced.

In short words, the principle of the globe valve is to use the stem torque to give the sealing surface a downward pressure. By relying on the pressure of the valve bar, the sealing surface of the valve flap and the sealing surface of the valve seat are closely fitted to prevent the flow of the medium or to adjust the flow rate of the medium. . The opening and closing member of the globe valve is a cylindrical valve flap having a flat or tapered surface, and the valve disc moves linearly along the center line of the fluid. The movement mode of the valve stem has a lifting rod type (the valve stem is lifted and lowered, the hand wheel does not move up and down), and there is also a lifting and rotating rod type (the hand wheel and the valve stem rotate together, and the nut is set on the valve body). The globe valve is a forced-sealed valve, so when the valve is closed, pressure must be applied to the valve flap to force the sealing surface to no leak.

Globe valve working principle diagramGlobe valve working principle


We assume that there is a pipe with a lid. Water flows in from the bottom of the pipe and flows out in the direction of the pipe. The cover of the outlet pipe is equivalent to the closing part of the globe valve. If the pipe cover is lifted up by hand, the water flows out. Cover the cap and the water stops flowing, which is equivalent to the working principle of the globe valve.


Globe valve closing principle

Globe valve schematic (closed state)Closed state of globe valve


The globe valve rotates the hand wheel to raise and lower the valve stem and drives the valve flap to be linearly displaced parallel to the flow direction of the medium to achieve the purpose of opening and closing. The hand wheel rotates clockwise, and the working medium enters through the channel below the valve flap. At this time, the applied sealing force must be equal to or greater than the sum of the force generated by the sealing surface and the pressure of the medium and the medium.


Globe valve opening principle

Globe valve schematic (open state)Open state of globe valve


When the globe valve is opened, the opening height of the valve flap is 25% to 30% of the nominal diameter, and the flow rate has reached the maximum, indicating that the valve has reached the fully open position. Therefore, the fully open position of the globe valve should be determined by the stroke of the valve flap.


Note: 1. The globe valve only allows the medium to flow in one direction and has directionality during installation.


2. The function of the globe valve is 0 or 1, that is, through or no through. That is to say, the globe valve is only suitable for full opening and full closing, and adjustment and throttling are not recommended.