Reasonable design, standardized construction, correct material selection, and strict quality inspection are indispensable links in the construction of any project. Building plumbing engineering is a sub project that requires coordination and cooperation with buildings, structures, electrical systems, and other related aspects. Poor construction quality control can lead to quality issues such as running, emitting, dripping, leaking, and blocking in the water supply, drainage, and heating systems after the project is put into use, causing inconvenience and inconvenience to residents and difficulties in future management work. How to ensure quality control during the construction process of plumbing engineering and create a good living environment for users is of great practical significance. The quality of steel pipe outer wire as a pipe fitting in plumbing engineering should be strictly controlled, and construction should be carried out in strict accordance with the requirements of the specifications. Relevant materials and equipment should be strictly inspected from the aspects of product qualification certificate, specification model, appearance quality, and material. For counterfeit and inferior products, asbestos should be used for the outer wire lining of thermal insulation pipe fittings, and the thread should be tight to ensure that there is no leakage or pressure drop, which is considered qualified.