영하 196℃ 초저온 배관에 사용되는 밸브로써 Packing의 동결방지를 위하여 Bonnet 길이를 길게 하여야 하며 Sub-Zero처리를 하여 실온에서 변형이 가는 것을 사전에 방지 하여야 한다. 이상승압을 방지하기 위해 Disc에 Vent Hole를 두어야 한다.기본적으로 급속하거나 빈번한 개폐 조작을 중요시 하지 않는 배관에 사용된다.
■ YOKE SLEEVE
The upper portion of the Yoke Sleeve is hexagonally tapered to fix the handwheel. The standard material of the Yoke Sleeve is Nodular Ni-resist D2 with over 1150℃(2100℉) dissolution point in accordance with API Std. specifications.
The body-bonnet bolts are manufactured in accordance with API Std. 600 specifications. The nuts also strictly conform with ANSI B 1.1 Strain-hardened austentic stainless steel.
Austenitic stainless steel used for bodies and bonnets offer excellent impact strength, minimize heat loss and protect against corrosion.
■ SEAT RING
The heat treated stem delivers adequate mechanical properties as well as excellent surface hardness. Further, opening/shutting friction is minimized by accurate machining and lapping.
■ FLEXIBLE WEDGE
The wedge seating surfaces have been accurately machined, grind and lapped to a mirror finish to prevent leakage and eliminate galling. Stellite 6 for all medium and high pressure application prevents selzing and galling.
TAustenitic stainless steel used for bodies and bonnets offer excellent impact strength, minimize heat loss and protect against corrosion.