Cryogenic Gate Valve -198 Deg C
Technical Summary
Szie Range: 1/4"~24"(DN6~DN600)
Pressure Range: 150LB ~ 2500LB, PN10~PN64
Application: Air separation plants, LNG storage and distribution,
LNG Transportation, Liquid and Gaseous Oxygen for steel production,
Etc.
Series in Range: Standard bore, reduced bore; Ball valve, Gate
valve, Check Valve, Globe valve, Etc.
Temperature Range: -196 Deg C
Standards: API 6D, API 607 for fire safe design, API600 / API603
for Gate valve, BS 1873, BS1868, Etc.
Material: Austenitic Stainless steel, ASTM A351, ASTM A182, Etc.
Operation: Lever / Handwheel, or gear operated, Pneumatic or
Electric Actuated. Etc.
End Connections: RF, RTJ. FF, Butt Welded, Extended Butt Welded,
Etc.
Cryogenic Definition:
Low-temperature parts into liquid nitrogen tank insulation a
certain length of time, to reduce its due to temperature
differences andmetallographic changes resulting from the
deformation,which increases when the low-temperature valve sealing
performance of a processing method.
Cryogenic method: soak the parts to be processed into liquid
nitrogen tank for cooling, when parts of 196 degrees centigrade
temperature reaches-, start insulation 1 ~ 2 hours, then remove the
carton natural treatment to room temperature, repeat cycle twice.
Austenitic stainless steel in Martensitic transition temperature,
part of austenite into martensite changes causing the resulting
volume parts deformation is an important reason for the valve
sealing surface leakage. Moreover, as the temperature decreases
parts produces shrink and thermal stress caused by the valve
irregular parts of deformation caused by low leakage is also one of
the reasons. To this end, before finishing of parts (e.g. sealing
surface grinding) on main parts such as: the valve body, valve
covers, plate (disc), the valve stem fasteners such as below the
operating temperature of cryogenic treatment.
As a general rule, use of the valve below 101C, before finishing
the main part for cryogenic. But if the user requires, above-101.C
working temperature valve parts for cryogenic.
