Cryogenic stop valve refers to a valve in which the closing member (valve disc) moves along the center line of the valve seat. According to this movement form of the valve disc, the change of the valve seat opening is proportional to the valve disc stroke. Since the opening or closing stroke of the valve stem of this type of valve is relatively short, and it has a very reliable shut-off function, and because the change of the valve seat opening is proportional to the stroke of the valve disc, it is very suitable for regulating flow. Therefore, this type of valve is very suitable for use as a cut-off or regulating as well as throttling.
1. Simple structure, convenient to manufacture and maintain.
2. The working stroke is small and the opening and closing time is short.
3. Good sealing performance, small friction between sealing surfaces and long service life.
(1) The structure is simpler than that of gate valves, and it is more convenient to manufacture and maintain.
(2) The sealing surface is not easy to wear and scratch, and has good sealing performance. There is no relative sliding between the valve disc and the valve body sealing surface when opening and closing, so the wear and scratches are not serious, the sealing performance is good, and the service life is long.
(3) When opening and closing, the valve disc stroke is small, so the height of the stop valve is smaller than that of the gate valve, but the structural length is longer than that of the gate valve.
(4) The opening and closing torque is large, the opening and closing is laborious, and the opening and closing time is long.
(5) The fluid resistance is large. Because the medium channel in the valve body is tortuous, the fluid resistance is large and the power consumption is large.
(6) Medium flow direction: When the nominal pressure PN ≤ 16MPa, downstream flow is generally used, and the medium flows upward from the bottom of the valve disc; when the nominal pressure PN ≥ 20MPa, countercurrent flow is generally used, and the medium flows downward from the top of the valve disc. To increase the sealing performance. When in use, the stop valve medium can only flow in one direction and cannot change the flow direction.
(7) The valve disc is often eroded when fully open.
Commonly used stop valves include national standard stop valves, American standard stop valves, German standard stop valves, Japanese standard stop valves, bellows stop valves, and low-temperature stop valves.
The valve stem axis of the cryogenic stop valve is perpendicular to the valve seat sealing surface. The valve stem has a relatively short opening or closing stroke and a very reliable cutting action, making this type of valve very suitable for cutting off or regulating and throttling media. Once the low-temperature stop valve is in the open state, there is no contact between its valve seat and the valve disc sealing surface, so the mechanical wear of its sealing surface is small, because the valve seat and valve disc of most stop valves are relatively easy to repair or There is no need to remove the entire valve from the pipeline when replacing the sealing element, which is very suitable for situations where the valve and pipeline are welded together. The flow direction of the medium changes when passing through this type of valve, so the flow resistance of the stop valve is higher than that of other valves.
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| Specification |
Details |
| Design Standard |
API 602 / ASME B16.34 |
| Pressure/Temperature Chart |
ASME B16.34 |
| Face to face Dimension |
CAMTECH Standard |
| Testing Standard |
API 598 |
| Flange Details |
ASME B16.5 |
| Socket-Weld End Details |
ASME B16.11 |
| Butt-Weld End Details |
ASME B16.25 |
| Screw End Details |
ASME B1.20.1 |
| Size Range |
1/2″ - 2″ (DN15 - DN50) |
| ASME Class |
150 - 1500 |
| Materials |
A105 / LF2 / F5 / F9 / F11 / F22 /
F316 / F304 / F316L / F321 / F51 /
F55 |
| Trims |
F6a / F316 / F304 / F316L / F321 /
F51 / F55 / Inconel / Stellied or
Hardfaced |
| Ends |
Flange ends, Socket Weld End,
Screwed End, Butt-weld End |
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