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CRYOGENIC VALVE

Cryogenic Service Valves

Cryogenic Gate Valves are specially engineered and designed for piping systems used in the storage and transport of liquefied gasses such as LNG and liquid nitrogen and oxygen. The main structural feature of these valves is an extended bonnet with an enclosed vapor chamber to isolate packing from the cryogenic fluid and thereby allow packing to function properly. PK Vlave Cryogenic designs and liquid nitrogen testing facilities go much further to assure proven performance in this most demanding application.

Material

Materials suitable for working condition must be adopted for low temperature valves. Especially in petrochemical industry, the types of fluids to be processed are different according to each section even in the same plants. At the same time, the temperatures used are also different. A full consideration must be paid to the selection of material.

Body And Bonnet

As for the materials constituting the low temperature valves, special consideration must be paid to the materials used at pressure parts as in the case of body and bonnet.

Trim

Following the body and bonnet, selection of materials for main parts such as stem, seat ring, and gland is very important. We adopt austenite stainless steel.

Packing

Teflon or other plastic packing protecting from shinkage by large cloumn of insulating gas.

Seating Surface

Stellite 6 for all medium and high pressure application prevents seizing and galling

Bolt and Nut

Material for bolts at low temperatures requires especially strength. Therefore, rigidity at low temperature is demanded and brittleness at low temperature of steel material can be improved generally by heat treatment. We use it according to ASTM standard.

Table of Liquefied Gasses

Production Materials

ASTM : A351-CF8, CF8M, CF3, CF3M or Equivalent