S-N Fatigue Strength of Small Diameter Branch Welded Pipe with Variation of Welding Shapes and Welding Procedures

Baek, Jong-hyun; Kim, Woo-sik

Journal of KWJS 2004;22(3):50-55.
Published online September 15, 2004.

[연구논문] 용접부의 형상과 공정변화에 따른 소구경 분기배관의 피로강도 특성평가

S-N Fatigue Strength of Small Diameter Branch Welded Pipe with Variation of Welding Shapes and Welding Procedures

Abstract

S-N fatigue tests were conducted to investigate the fatigue strength of small diameter socket and butt welded joints made of carbon steels. Experimental parameters were pipe diameter, throat depth, shape of socket welds and welding procedure. Filler metals used in SMAW and GTAW procedure were E9016-G with diameter of 4.0 mm and ER70S-G with diameter of 2.4 mm. API 5L Gr.B pipes were adopted as a small diameter branch pipes. All socket fittings were machined from ASTM A I 05 carbon steel. Tensile strength was not affected by the welding procedure. Fatigue strength in socket weld joints increased with increasing pipe diameter, area of weld metal and weld leg length of pipe side.