Also known as squareandrectangularcoldbendinghollowsection,referredtoas"squareandrectangulartubes,code FandJ,respectively 1,theallowabledeviationinthewallthicknessofthemoment, when thewallthickness is notmorethan10mmshallnotexceedthe nominal wallthicknessofplusorminus10%,whenthewallthickness is more than 10mmforthewallthicknessofplusorminus8%, except cornersandweldareawallthickness.2,thetorquetubeusually delivery length is 4000mm-4000mm,6000 mmand12000mminthe majority. Torquetubeallowdeliverynotlessthan2000mmshortfeet and thelengthoftheproduct,canalsointerfacetubeformdelivery, butthebuyerwhenuseinterfacetubeshouldberemoved.Short feet and nonscaleproductweightisnotmore than5%ofthetotal amountofdelivery,fortheoreticalweightgreaterthan20kg/msquare torque tubeshallnotexceed10% ofthetotalamountofdelivery3, square torque tubebendingshallnotbegreaterthan2 mmpermetre,total bending shall not begreaterthan0.2%ofthetotal length