Highlight: Flange-Connected Straight-through Globe Valve
Product introduction:
Globe valves, also known as stop valves, belong to the category of forced-sealing valves. The axis of the valve stem is
perpendicular to the sealing surface of the valve seat, and the valve opens or closes by driving the valve core to move up
and down. Its opening and closing component is a plug-shaped disc with a flat or conical sealing surface. The disc moves
linearly along the centerline of the valve seat. Therefore, when the valve is closed, pressure must be applied to the disc to
force the sealing surface to prevent leakage. When the globe valve is opened, the opening height of the disc indicates 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 disc.
Product technical parameters:
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Nominal Pressure PN(MPa)
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1.0 - 4.0
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Nominal Diameter DN(mm)
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15~600
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Test pressure (MPa)
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Strength (water)
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1.5 times of pressure nominal
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Sealing (water)
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1.1 times of pressure nominal
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Sealing (Air)
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0.6 times of pressure nominal
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Sealing for bellows (water)
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1.5 times of pressure nominal
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Raw material
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WCB, CF8, CF8M
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Medium suitable:
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Water, steam, oil mediums
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Working temperature
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-196℃~600℃
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Connection type
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Flange
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Operational method
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Hand-wheel, bevel gear, pneumatic and electric actuators
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Product features:
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Structurally, globe valves are simpler than gate valves. The valve body and disc have only one sealing surface, making them better in manufacturing processability, easy to fabricate and maintain. They apply to a wide range of pressures, suitable not only for medium and low pressures but also for high pressures. During full closure, the disc stroke of a globe valve is short, so its height is relatively smaller than that of a gate valve.
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The opening height of a globe valve is small during opening and closing, generally only 1/4 of the valve seat passage diameter. It features a highly reliable shut-off action and is easy to regulate flow.
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In terms of service life, once in the open state, there is no longer contact between the valve seat and disc sealing surfaces, which are less prone to wear and abrasion, thus extending the service life of seals.
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Globe valves only allow unidirectional medium flow and have directionality during installation. The structural length of a globe valve is longer than that of a gate valve.
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Globe valves have larger opening and closing torques, making rapid operation difficult. The internal flow path is tortuous, resulting in high fluid flow resistance and significant hydrodynamic loss in pipelines.
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When the medium enters the valve from below the disc, the resistance that the operating force needs to overcome is the friction between the stem and packing, plus the thrust generated by the medium pressure.
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The force required to close a globe valve is greater than that to open it, so the stem diameter must be large; otherwise, stem bending failure may occur.