Welded steel pipe: Chitoliro chachitsulo chokhala ndi msoko pamwamba pa chingwe chachitsulo kapena mbale yachitsulo yomwe imakhala yopindika komanso yopindika kukhala yozungulira kapena yozungulira. Khoma lamkati la chitoliro chowotcherera lili ndi nthiti zowotcherera. The mankhwala waukulu monga: ERW zitsulo chitoliro, LSAW zitsulo chitoliro ndi SSAW zitsulo chitoliro. Chitoliro chachitsulo ndi mtundu wachitsulo chopanda dzenje, chomwe chimagwiritsidwa ntchito ngati ngalande yotumizira madzi, monga mafuta, gasi, madzi, gasi, nthunzi, etc.