The purpose of this standard is to establis the dimensions in millimeters and the delivery conditions of longitudinally welded square and rectangular tubes in non-alloy steel, made from hot-rolled flat products. These tubes are commonly used in various mechanical and construction industries, for example: furniture, automobiles, locksmithing, etc...
NT 26.04-1983 history
1984NT 26.04-1983 Square and rectangular steel pipes are designed to be formed during high temperature rolling