CPC F16K 1/38 (2013.01) [F16K 1/48 (2013.01); F16K 25/005 (2013.01)] | 12 Claims |
1. A cryogenic globe valve comprising:
a body portion;
an axial cylindrical portion having a long-neck structure extended into the body portion;
an elongated stem having an insertion portion provided in a lower of end of the elongated stem; and
a resin-made valve disk attached to a lower end of the elongated stem, the resin-made valve disk having a conical surface defining a reduced-diameter tapered shape,
wherein an attachment portion is provided in an upper part of the resin-made valve disk, and the attachment portion is inserted into the insertion portion of the elongated stem,
a through hole is formed in a direction intersecting a length direction of the stem in the insertion portion and the attachment portion,
a fixing member is inserted into the through hole to attach the attachment portion and the insertion portion to each other,
a gap is provided between the fixing member and the through hole to maintain a clearance in which the resin-made valve disk is movable when the resin-made valve disk thermally contracts, and
a vertical width of the clearance between facing surfaces of the through hole and the fixing member under an extremely low temperature condition is set to 0.5% or more of a seal diameter of the resin-made valve disk such that the resin-made valve disk is three-dimensionally operable with respect to the stem even under an extremely low-temperature condition.
|