An old long lathe is changed to LJ8510/CGL type
keyway broaching machine. It accords to green manufacture requirement and
reduces retrieved costing. With general hydraulic pressure elements, energy saving hydraulic control system is composed and automation of machine tool has been advanced. Designed frame bears pulling and cutting forces in the direction of level axes due to pulling tool drove by hydraulic oil. The
structural stability of the main frame is calculated and analyzed based on the principle of steel structure. In the light of probable previous invalidation of single arm as it is loaded, its stability has been calculated when the bending moment operates inside and outside the main axis plane. The refitted hydraulic control system meets pulling and cutting requirements of the system. And run-in operates normally and continuously for 4 hours with the rise of oil temperature being lower than 20℃. The quality of this system has achieved ISO level and the method of design and analysis is worthy to spread.