Research In Crankshaft’s Key Maching Process Of Medium Speed Diesel Engine

In recent years, the domestic and foreign market demands for a large quantity of dieselengines, which are mainly used in railway locomotives, ships and generator sets.By understanding the market, we know that the output of the crankshaft determines theproduction of diesel engines, because of its specificity and longer production cycle. Therefore,improving the productive efficiency of crankshafts production has become the researchingtopic of many domestic and foreign corporations.According to the market demand, Dalian Locomotive and Rolling Stock Co LTDintroduced advanced diesel technologies from abroad, while recommending the improvedmature product—the240type diesel engine to the market. This issue, which is selectedaccording to the needs of projects introduced by Dalian Locomotive and Rolling Stock Co.LTD in recent years, is considered as the key researching and developing project by theMinistry of Railways and China North Vehicle Group that has invested large numbers ofmoney and manpower to introduce foreign projects.This article described the production situation and the actuality of the medium-speeddiesel engine crankshaft yielded by Dalian Locomotive and Rolling Stock Co. LTD in detail,and respectively discussed structures of the cast iron crankshaft and the forged steelcrankshaft of the medium-speed diesel engine, traditional technological processes andequipment status, and also systematically analysed and researched processing methods ofadvanced equipments by studying domestic and foreign manufactures and applying advancedequipments that the corporation brought in.We adopt effective measures, such as scientifically arranging processes and choosingprocessing equipments, to ensure the processing accuracy of the crankshaft and improve theproduction efficiency.By designing and manufacturing the eccentric fixture and the eccentric centre frame andapplying them in the lathe for spindle neck, we can improve the processing quality and theproduction efficiency of the procedure that is finishing turning crank pins by using thecircular cutting disc lathe in originally traditional processes; by researching the application ofthe turning and milling centre that we brought in, we have compiled processes andmanufacturing programs to instead of original processes and solved some quality problemsconsisting in original procedures; more over, we also have investigated the whirlwind typemilling machine and the dynamic grinding machine being about to be brought in and analysedprocesses, and also compiled processing programs to improve the roughing efficiency offorged steel crankshafts and the spindle quality in the finishing grinding procedurerespectively. Medium-speed diesel engine crankshafts that Dalian Locomotive and Rolling Stock Co.LTD manufactures are mainly made of cast iron. In comparison with cast iron crankshafts,forged steel crankshafts are produced less and its production efficiency is low. By researchingthe process flow of the cast iron crankshaft and the forged steel crankshaft in this paper, wecan make rational use of limited resources, and improve the crankshaft productive efficiency,and also provide the basis for business planning of the future direction.