Analysis Of Offshore Platform Pipe Double-wire Submerged Arc Welding Technology

Offshore platform pipe is an important part of offshore platforms. The manufacturingtechnology of domestic offshore platforms pipe is lagging behind. At home, most of the pipeproduction lines adopt manual metal arc welding scratch coat and single-wire submerged arcwelding screen welding method, carbon arc air gouging cleaning weld root. This weldingprocess is inefficient, labor-intensive and produces heavy pollution. For the pipe productionline in Tsingtao base of CPOE, a new welding technology with high quality and efficiency isneeded to improve the quality and efficiency of the production of the offshore platform pipe.This paper puts forward solutions to existing welding problems in the following aspects,the choice of welding materials, optimization of STT（Surface Tension Transfer） equipmentand technology parameters, optimization of double-wire submerged arc welding equipmentand technology parameters. The welding tests, non-destructive testing, tensile test hardnesstest, grooving hammer breaking test, bending test as well as low-temperature impact test aredone to check the double-wire submerged arc welding technology.CTOD (Crack Tip Opening Displacement) fracture mechanics is adopted to help judgewhether the welded joints have sufficient fracture toughness. And that can ensure theperformance of the welded joints meet the requirements. ANSYS finite element software isadopted to simulate the temperature field of the single and double wire submerged arcwelding process. And by comparing these two kinds of results, the advantages anddisadvantages of both methods can be easily seen. Also the optimal double wire spacing canbe determined by analyzing the results with an experiment done to check and verify thisspacing.