Determining Impact of Groove Depth on the Repairing of Groove on the Surface of General Structural Steel by Using Taguchi Method

If pipelines are damaged or fail to function normally, downstream units will stop operation, daily activities will be disrupted, or the process will shut down. Awareness of and knowing about the condition of pipelines in service as well as recognizing the cause of failure and then taking timely measures to make appropriate changes can increase productivity. One of the appropriate measures is to repair the surface crack of steel pipelines using different welding methods. Two variables of crack width and crack depth are common in all the repair methods. In this research, the first variable is the crack depth and other variables are considered the second variables. Thus, the effect of crack depth on the repairing of steel surface crack is determined using Oxyacetylene Flame Welding with Spray of Pure Iron Powder. The test results are analyzed and then compared using the Taguchi test design method with one factor at one level (one-factor ANOVA). Investigating and analysis of the results showed that the contribution of crack depth variable in Oxyacetylene Flame Welding with Spray of Pure Iron Powder is 34.2%, 14.6% and 91.5% to achieving the yield strength, tensile strength and elongation of base metal, respectively. Thus, to achieve strength (tensile or yield) in the base metal, studying the effect of crack depth is not enough by itself; however, to achieve relative elongation of the base metal, the most effective variable is crack depth (91.5% contribution).

Flame Welding, One level, One variable, Oxyacetylene