STAINLESS STEEL PIPING AND METHOD FOR JOINING STAINLESS STEEL PIPING

摘要

PROBLEM TO BE SOLVED: To provide stainless steel piping which prevents the occurrence of a dead space to the inner surface of the joint part of stainless steel piping, and is extremely less in contamination by metal fine particle based on fume, and prevents feed gas from being contaminated by impurities, and is extremely excellent in corrosion resistance of a joint.;SOLUTION: When the end parts of stainless steel pipes to be joined together are abutted against each other and joining is effected by welding after the inside of the pipes is brought into a state under back shield gas atmosphere or vacuum environment, joining is carried out in a way that only the outside part of the wall of the pipe is molten to form a melting joint part W. It is preferable that a content of oxidizing gas under back shield gas atmosphere and vacuum environment is set to 10 ppm or less, and surface roughness is set to 30μ or less. In case thickness t of a steel pipe exceeds 1 mm and penetration depth tw of the melting joint part is set to t-0.7≤twt(mm). In case the thickness t is 1mm or less, it is preferable that the penetration depth tw of the melting joint part is set to ttw≥0.3t(mm).;COPYRIGHT: (C)2006,JPO&NCIPI