Views: 0 Author: J-VALVES Publish Time: 2026-09-02 Origin: Site
Liquefied Natural Gas (LNG) operates at cryogenic temperature down to‑196℃. Rapid vaporization, cold brittleness, frost and icing on stem and packing are common risks for valves in LNG circuits. Ordinary general‑purpose ball valves cannot withstand such extreme cold. Low temperature transfers directly to packing boxes, hardening packing material and causing external leakage. Without proper isolation performance, whole LNG facilities may face shutdown and safety hazards.
Within LNG storage tanks, loading arms, regasification stations and liquefaction plants, isolation valves are critical hardware for process safety. Standard room‑temperature ball valves are not fit‑for‑purpose. Specially engineered long‑stem cryogenic ball valves are needed for safe shut‑off under‑196℃ conditions.
The long stem design is not a simple mechanical extension. It follows design specifications from ASME B16.34 and API 6D for cryogenic valves. By lifting the packing box away from cryogenic zones, packing components stay within a suitable temperature range, minimizing cold transfer and reducing risk of packing leakage.
‑196℃ long stem cryogenic ball valves serve as isolation and shut‑off units for LNG circuits. They provide positive isolation during equipment maintenance and pipeline switching operations.
Body materials commonly include WCB, LCB, LF2 forged steel. Internal trim adopts low‑temperature stainless steel with cryogenic impact test certification to prevent cold‑brittle fracture at‑196℃. Special low‑temperature seat sealing combinations balance sealing performance and operating torque.
Long stems are subjected to cryogenic stress‑relief treatment to minimize thermal deformation. Anti‑blow‑out stem structure complies with API 6D safety requirements.
1. Elevate packing box to limit cold conduction and prevent packing freezing failure.
2. Compatible with pipeline cold‑insulation layers. Valve body can be fully wrapped by insulation while stem extends outside insulation for handwheel or actuator mounting.
3. Simplify on‑site operation and maintenance without damaging pipeline thermal insulation.
1. Inlet & outlet isolation for LNG storage tanks
2. LNG tanker loading‑unloading arm pipelines
3. LNG regasification and peak‑shaving station process lines
4. Cryogenic process loops in liquefaction plants
5. Transfer pipelines for cryogenic liquid media
Note:‑196℃ long‑stem cryogenic ball valves are intended for shut‑off and isolation service. When specifying, confirm pressure class, medium, actuation type and test requirements. Valves shall pass cryogenic shell and seat leakage tests in accordance with industry standards to match project conditions.
Many projects only focus on nominal pressure while overlooking cryogenic‑specific requirements.
1. Verify rated working temperature down to‑196℃ together with cryogenic impact test documents for materials.
2. Long stem dimension is not universal; dimension shall match thickness of on‑site thermal insulation.
3. Prefer valves designed per API 6D, ASME B16.34 and request cryogenic sealing test reports.
4. Clarify service condition: this ball valve is optimized for on‑off isolation, not intended for continuous throttling service.
Designed with extended stem structure and cryogenic‑qualified material sets,‑196℃ long stem cryogenic ball valves follow well‑recognized international valve standards. They resolve typical pain points including cold conduction, frost formation and seal failure, acting as proven reliable isolation solution for LNG tanks, loading‑unloading and regasification processes. Clearly define temperature rating, stem length, material specification and cryogenic test requirements in technical datasheets to reduce operational risks in field service.
