Abstract: Elaborated in the paper are the equipment composition of the mandrel bar cooling area in the process layout of the mandrel mill plant for hot-rolled seamless steel pipes. According to their different structures， the mandrel bar transfer devices in the area fall into three types，i.e.，the walking-beam，the crank & rocker，and the lifting flap. The advantages and disadvantages of each of the three types are compared and analyzed. As a result，it is identified that the walking-beam structure features high technological integrity and easy control，the crank & rocker mechanism is advantageous in easy point-check and maintenance， and the lifting flap structure stays with high investment effectiveness. When designing the layout of the mandrel bar cooling area，effectively integrating the above mentioned advantages and disadvantages and of the different transfer units should be considered.