What is a globe valve?
The opening and closing parts of the globe valve are plug shaped disc, the sealing surface is flat or conical, and the disc moves in a straight line along the center line of the fluid. Stem movement form, there are lifting rod type (stem lifting, handwheel not lifting), there are lifting rotary rod type (handwheel and stem rotating lifting together, nut in the valve body). Globe valve is only suitable for full open and full closed, not allowed for adjustment and throttling.
Globe valves are forced sealed valves, so when the valve is closed, pressure must be applied to the disc to force sealing surface does not leak. When the medium from below the disc into the valve six, the resistance to overcome the operation force is the friction force of the stem and packing and the thrust produced by the pressure of the medium, the force of closing the valve is larger than the force of opening the valve, so the diameter of the stem should be large, otherwise the failure of the stem top bending will occur. In recent years, since the emergence of the sealing valve, the flow of the medium of the globe valve is changed from the top of the valve into the valve chamber, then under the action of the medium pressure, the force of closing the valve is small, and the force of opening the valve is large, and the diameter of the stem can be reduced accordingly. At the same time, under the action of the medium, this form of valve is also more rigorous. China’s valve “three to” has stipulated that the flow direction of the globe valve is top-down.
When the globe valve is opened, the opening height of the valve disc is 25% to 30% of the nominal diameter, and the flow has reached the maximum, indicating that the valve has reached the full open position. Therefore, the full open position of the globe valve should be determined by the stroke of the valve disc.
Globe valve can be divided into: globe valve, threaded stem globe valve, threaded stem globe valve, straight-through globe valve, Angle globe valve, three-way globe valve, straight-flow globe valve, plunger globe valve, needle globe valve.
Nortech is one of the leading industrial valve manufacturers in China with quality certification ISO9001.
Major products: Butterfly Valve, Ball Valve,Gate Valve, Check Valve, Globe Vavlve,Y-Strainers, Electric Acurator , Pneumatic Acurators .
Post time: Sep-17-2021