The disc of one globe valve is plug-type disc. Its surface is flat-face or cone-face. Disc continues in motion along a straight line of the fluid. The movement is in the form of lift (stem lift, hand wheel does not lift), and lift rotating rod (hand wheel is rotated and lifted along with stem, and nut set on the body). Globe valve is only used at  full-open condition or full-close condition, and flow control measures would not be advised.


Globe valve is part of forced sealing valves, and it is the reason why a worker must press on a disc to avoid leaks when a valve is closed. When entering from the bottom of disc, resistance force caused by the fluid which is required to overcome operating force is a kind of friction force between the stem and the packing and the thrust produced by the pressure of the medium. The force of closing the valve is greater than the force of opening, so the diameter has to be big. Recently, since the appearance of self-sealing valve, the fluid must flow from the top to valve chest. At this time, under the pressure of medium, it is easy to close while hard to open. So diameter is reduced. 


When a globe valve is opened and the altitude of disc reaches 25% to 30% of nominal diameter, this valve is full open. Globe valve has the following advantages:

1. The structure is simple, manufacture and maintenance is more convenient.

2. The working stroke is small, the opening and closing time is short.

3. Good sealing, sealing surface between the friction force is small, long life.

Globe valve defects are as follows:

1. Fluid resistance, open and close when the required force is large.

2. Do not apply with particles, viscosity, easy to medium coke.

3. Poor regulation performance.

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China Gate Valve, China Ball Valve, China Butterfly Valve, Welcome to contact us by Email:info@tjlindustry.com

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