%0 Journal Article %A Sabokrouh, M. %A Farahani, M.R. %T Analysis of Variance of Residual Stress Distribution in Girth Welding of High Strength Low Alloy Steel Gas Pipeline %J Modares Mechanical Engineering %V 19 %N 7 %U http://mme.modares.ac.ir/article-15-21524-en.html %R %D 2019 %K Residual stress, ANOVA, Girth weld, Hole drilling strain gage test, Approximation functions, %X In this paper, the analysis of variance (ANOVA) of weld residual stress distribution (using the hole drilling strain gage method according to ASTM 837 standard) was investigated (in the hoop and axial direction of the 56-inch gas transmission). The results of ANOVA show that the best distribution curve of residual stress is the third order function (3 degree of freedom) in the distribution diagram of hoop and axial residual stresses. In this order, the p value of the hoop and axial residual stress is 0.044 and 0.001, respectively. This indicates the high reliability of the third order function. Also, the value of F and coefficient of determination of this order has an appropriate value. In addition, due to the high p value and low reliability, the 5-order approximation function is not a suitable residual stress distribution curve compared to the third order function. Order approximation functions (2 and 4) have lower reliability (higher p value) and lower F value than odd order (3 and 5). Despite having the highest freedom with the highest p (lowest reliability), the lowest F, and the lowest coefficient of determination, the second-order function, is the most inappropriate approximation function. Despite the existence of residual stress with respect to the zero experimental residual stress compared to the approximation function, the use of strain test in points far from the weld one and the base metal is not essential. %> http://mme.modares.ac.ir/article-15-21524-en.pdf %P 1789-1795 %& 1789 %! %9 %L A-10-18572-5 %+ School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran %G eng %@ 1027-5940 %[ 2019