ASTM A671/A672 CL42 STEEL PIPE

HFW Welded steel pipe

Standard:ASTM A671/A672 CL42

Sizes:406.4MM--1420MM

Brand: BRISK STEEL

The HFW welded pipe covered by the ASTM A671/A672 standard is an electric fusion welded steel pipe specially used for low temperature and high pressure working conditions. The standard is divided into multiple grades such as CC60/CC65 according to the use temperature. Among them, the CC65 grade requires the steel pipe to maintain good toughness at a low temperature of -45℃. This type of steel pipe is made of hot-rolled coil by high-frequency resistance welding process. The typical specifications are 114-1422mm in diameter and 3-40mm in wall thickness. It has the characteristics of stable weld quality and high dimensional accuracy. ASTM A671 is suitable for normal temperature and low temperature environments, while A672 is designed for higher pressure conditions. Both require the weld area to undergo complete heat treatment to eliminate stress. The standard places special emphasis on the low-temperature impact performance of the material and requires the Charpy V-notch impact test to reach a specific energy value at a specified temperature (such as CC65 grade requires ≥27J at -45℃). Unlike the API 5L standard, A671/A672 has higher requirements for the hydrostatic test pressure of steel pipes, usually reaching 1.5 times the working pressure. This type of steel pipe is widely used in key facilities such as liquefied natural gas (LNG) receiving stations and cryogenic storage tanks. For example, the cryogenic pipeline systems of many LNG receiving stations along the coast of my country all use this standard product. The standard also allows the customization of special chemical composition and mechanical properties according to engineering needs, providing reliable protection for pipeline safety in extreme environments.