Abstract: Elaborated here are the manufacture and check activities of the rolling stands of the Φ273 mm 3-roll mandrel pipe mill, focusing on investigation and analysis of the causes for nonconformance of the stands.It is identified that the main cause is the processing defect of the swing rack which is one of the three major parts of the rolling stand.Accordingly the said rack is modified in terms of processing method and processing technology.As a result, the qualification rate of the rolling stands has been increased from the original 50% to 92.3%.