Cryogenic top-entry ball valves are manufactured for extremely low temperature and cryogenic applications where in-line disassembly is required for trim inspection and maintenance.Valves are designed with an integral bonnet extension which prevents cryogenic liquids from reaching the stem packing by enabling the liquids to boil and convert to gas. This minimizes the energy loss along the extension and protects the valve from malfunctioning. The structural integrity of the valve reduces any thermal deformation of internal components caused by temperature variance to a minimum, ensuring the highest level of performance for tight shut-off in critical LNG fields.Features and benefits

DESIGN FEATURES:
● Meets ASME B16.5, ASME B16.34, API 608, API 598.
● Face-to-face dimensions meet ASME B16.10 long pattern.
● Gear actuator standard on NPS 8–24 (DN 200–600) SB-150/300 and NPS 6 –12 (DN 150–300) SB-600 valves..
● Long cycle life.
● Low torques.
● Blowout-proof stem.
● Stem bearing reduces side thrust.
● Multiple solid PTFE or chevron type stem seal (adjustable).
● Live-loaded thrust washer prevents galling and provides secondary stem seal.
● Fully enclosed spiral wound graphite filled stainless body gasket.
● Locking devices optional on NPS 1⁄2– 6 (DN 15–150) valves (SB-600 up to NPS 4 (DN 100)).
● Air vent on all balls.
● Fire safe to API 607, BS 6755: 1) Body gasket SS 316 and graphite (standard); 2) Ball seats on body edge; 3) Stem shoulder seats on body.