The Paton Welding Journal, 2011, №09



2011 №09 (10)

2011 №09 (02)

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The Paton Welding Journal, 2011, #9, 2-9 pages  

HYDROGEN BEHAVIOUR IN REPAIR WELDING OF THE MAIN PIPELINES UNDER PRESSURE

V.I. MAKHNENKO, O.I. OLEJNIK and A.P. PALTSEVICH

E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
 
 
Abstract
Possibility of diffusion hydrogen penetration from hydrocarbon gas transported through the gas pipeline during repair welding performance on an operating pipeline has been analyzed. It is shown that at partial pressure of diffusion hydrogen on the inner surface of steel pipe in the range of 0.10-0.75 MPa at residual wall thickness in the defect zone of more than 5 mm increase of the parameter of hydrogen (cold) cracking risk is not higher than 5-11 %. Values of experimental measurements of diffusion hydrogen flow through the pipe wall in operating pipelines are given.
 
 
Keywords: repair arc welding, operating gas pipelines, diffusion hydrogen, gas pipeline wall, hydrogen cracks, risk of formation
 
 
Received:                ??.??.??
Published:               28.09.11
 
 
References
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