The invention relates to a tool and a method for
machining a
crankshaft of a medium speed
machine. The
machining tool is provided with a cutter for
machining a load release groove, a R40 special molding cutter for machining the surface of a balance block and a plug of a crossed hole of a
drill gun. The machining method comprises: firstly, according to the prior method, a
crankshaft billet of the medium speed
machine is subjected to primary TR
forging and molding; a main journal, a turning journal, the load release groove, the output end of the load release groove and a free end
flange are subjected to machining; the milling balance block ,the shape of a turning arm, and end
flange drilling are evenly distributed with holes and screw holes are subjected to machining; the main journal and the turning journal are ground and are subjected to final finishing; subsequently, the load release groove is processed through the cutter for machining the load release groove from outside to inside for a few times by
delamination. The R40 special molding cutter is used to
machine the surface of the balance block in a vertical
cutting mode. The
gun drill drills and cuts a guide hole and an oil hole to a crossed hole, and a plug is adopted in the crossed hole. A phi 700
flange hole is drilled through an aiguille and is machined through a Mohs lengthening
drill bush. The tool and the method for machining can ensure the quality of a product and greatly improve production efficiency.