Abstract: Described in the article are the manufacture process and movement principle of the walking beam cooling bed incorporated into the Ф159 mm mandrel pipe mill line,focusing on deduction of a set of formulas suitable for designing tooth profile of cooling beds of the said type. With such formulas,the cooling bed tooth profile design can be optimized theoretically or in actual case. Furthermore,with the Excel form,analysis of the tooth profile via confirmatory calculation can be performed easily and quickly.