ABSTRACT This study was planned as a part of a test program to confirm the effect of girth welds on the strain capacity of pipes. In this study, full-scale pipe bending tests are performed by using X80 SAW pipe. This paper covers pipe manufacturing procedure, developed welding procedure to obtain even match weld metal and properties of welded joints. And this work demonstrated that the X80 pipes welded under the developed procedure fractured in base metal remote from girth welded portion by full scale pipe bending test conducted under the internal pressure of 72 % SMYS of X80. INTRODUCTION Oil and gas exploration from extreme region such as remote areas, arctic areas and so on will increase due to extensive needs for oil and gas resources. High strength steel pipe (X80 and over) for gas transmission pipelines has been developed to reduce the gas transportation by high-pressure operation. To maximize economic advantages, the use of high strength steels in pipeline systems has been investigated. X80, X100 and X120 grade steels have been developed and utilized for gas pipeline
