Cast steel globe valve
Text description:
A globe valve is a valve in which the closing element moves in a straight line along the centerline of the valve seat. Due to the relatively short opening or closing stroke of the valve stem, the variation of the valve seat opening is directly proportional to the stroke of the valve disc, and it has a very reliable cut-off function, which is very suitable for regulating flow. Globe valves are generally connected to pipelines through flange or welding connections. Cast steel globe valves can be reliably and stably applied in high and low pressure applications such as steam, air, gas, oil, and oil and gas.
Structure and characteristics:
1. A globe valve relies on the pressure of the valve stem to tightly fit the sealing surface of the valve disc and the sealing surface of the valve seat, preventing the flow of medium. Belongs to a forced sealing valve.
2. There are two types of flow directions for the medium in the shut-off valve: "low inlet and high outlet" and "high inlet and low outlet". Only one-way flow is allowed for the medium, and there is directionality during installation.
3. The structural forms of the globe valve body include through type, direct flow type, and right angle type.
4. When the shut-off valve is opened, when the opening height of the valve disc reaches 25% to 30% of the nominal diameter of the shut-off valve, the flow rate has reached its maximum, indicating that the shut-off valve has reached the fully open position.
5. The structure of a globe valve is simpler than that of a gate valve, making it easier to manufacture and maintain.
6. The sealing surface is not easy to wear and scratch, with good sealing performance. There is no relative sliding between the valve disc and the valve body sealing surface during opening and closing, so the wear and scratch are not severe. The sealing performance is good, and the service life is long.
7. When opening and closing, the valve disc stroke is small, so the height of the globe valve is smaller than that of the gate valve, but the structural length is longer than that of the gate valve.
8. The opening and closing torque is large and laborious.
9. The fluid resistance is high due to the tortuous medium channels in the valve body, resulting in high fluid resistance and high power consumption.
10. When fully open, the valve disc is often eroded.
Design specifications:
Design standards: API 623, BS 1873, ASME B16.34, GB/T12235
Structural length: ASME B16.10, GB/T 12221
Connection standards: ASME B16.5, GB/T 9124, JB/T 79, HG/T 20592, ASME B16.25
Pressure test: API 598, GB/T 13927, GB/T 26480, JB/T 9092
Pressure and temperature rating: ASME B16.34, GB/T12224
Performance parameters:
Main materials: carbon steel, stainless steel, alloy steel
Nominal diameter: NPS 2 "to NPS 24", DN50 to DN600
Pressure range: CL150~CL2500 PN10~PN420
Working temperature: -196 ℃~+600 ℃
Application scope: It can be applied to cut off or regulate fluid pipelines such as tap water, sewage, construction, food, electricity, medicine, metallurgy, light textile, energy, etc., as well as for throttling purposes.