Pipe End Round Forming Equipment and Control System-The Fundamental Solution for Reducing Welding Defects in Offshore Pipeline Constructions-

摘要

In offshore pipeline constructions,high productivity is required to minimize pipe laying cost.One of the most significant me thods for achieving higher productivity is to reduce the welding defects,which require much repair duration. Recently,the acceptable level of welding quality,especially the root pass,becomes higher and higher.This means minimiz- ing fitting misalignment between both pipe ends is required to get rid of welding defects triggers.On the contrary,the toler- ances of commercially manufactured pipes have been same and their shape fluctuation between both pipe ends is not ideal for welding conditions.To solve this problem fundamentally,the authors have developed the pipe end round forming equipment to aim at perfect fitting alignment between both pipe ends for girth welding. The shape equalization between both pipe ends by this forming equipment,will lead to not only elimination of welding de- fects but also reduction of pipe fitting duration prior to girth welding and will contribute to improve pipe laying productivity.