Study On Casting Technique Of High-power Mud Pump Three-cylinder Crankshaft

Three-cylinder mud pump is widely used in geological prospecting work. Crankshaft is the most important key transmission components, and it is an important safety components. Crankshaft must have sufficient stiffness and fatigue strength in order to ensure reliable operation of mud.Based on the analysis and research of the domestic and foreign crankshaft material,rough processing technology status and the casting process of Shijiazhuang Coal Mining Machinery Co., Ltd,in order to draw the best casting process of crankshaft,so we can produce a cost-effective crankshaft which has the optimal combination of strength and tough.By analyzing the various factors influencing casting quality of crankshaft,the thesis describes the formation mechanism of casting defects.Design of riser using moduli progressive solidification method to feeding the casting.By rational design using internal and external chill to reduce the hot spots in casting,the crankshaft can form a bottom-up freezing to reduce the feeding pressure of riser.The reasonable gating system and pouring time has been designed to reduce the tendencies of casting defects such as sand inclusion and blowhole.By setting reasonable shrinkage rib improve the resistance of thermal cracking.By designing the proportion process of the molding sand,coating and drying technics the casting defects such as sand inclusion and blowhole can be reduced.The crankshaft material is ZG40MnB,the steelmaking process is oxidation-blowing in electric arc furnace.By studying the crankshaft ingredients ZG40MnB steel smelting,melting phase,oxidation period,such as smelting reduction process of control, ensure the quality of ZG40MnB smelting material.The steel is tapped with slag and poured after the steel is killed.Reasonable pouring process has been designed ensure the riser to maintain a high enough temperature and liquid steel feeding the casting.Design the thermal cutting process of riser to reduce the tendency of cold cracking.The internal organization of the crankshaft is thinned and the intensity is increased through the normalization.Through studying the casting process of the pump crankshaft,this subject determine the best solution, molding process,smelting technology,clean technology and other technical parameters.The key technical challenges of eliminating the Shrinkage at the crankshaft crankpin and the cast crack at the intersection of the neck and middle Crankpin has been solved.The yield of casting crankshaft has been improved from 40% to 97%.Good economic and social benefits has been achieved.