全纤维曲轴锻件曲柄臂平衡块安装面形状数值模拟

Numerical simulation of crankweb counterweight mounting surface for continuous grain flow crankshaft

采用弯曲镦锻法锻造中高速柴油机曲轴时,曲轴锻件曲柄臂安装面极易出现塌角缺陷。针对平衡块安装面为平面类型的曲柄臂,以16V240曲轴为研究对象,设计了4种平衡块安装面形状的曲柄臂锻件,并采用有限元法模拟了16V240曲轴锻件4种方案的RR法镦锻成形过程。从镦锻过程金属坯料的流动速度和速度矢量方向两个方面讨论了4种平衡块安装面形状对曲柄臂锻件成形质量的影响,模拟结果表明,设计为收敛形状的平衡块安装面在锻造过程中能有效避免塌角缺陷。根据方案4的模拟结果优化设计了模具并进行了曲轴单拐的挤压实验,实验结果与数值模拟结果基本一致。

The underfill defect is easy to appear on the mounting surface of crankweb when the crankshaft of high speed diesel engine is forged by bending and upsetting method. For the planar mounting surface of crankweb 16V240, a erankweb forge piece with four different shapes of mounting surface was designed, and their forging processes with RR forging method were simulated by FE method respectively. The influences of the four shapes of counterweight mounting surface on the forging quality of crankweb were analyzed by the flow velocity and velocity vector of metal blank during the forging process. The simulation results show that the convergence shape of mounting surface can avoid the underfill defect efficiently during the forging process. New die was optimally designed in accordance with the simulation results of plan No. 4, and the extrusion test of single crank was carried out, which shows that the testing result is basically identical with the numerical simulation result.