卧螺过滤离心机机械振动和动载荷的分析与研究

Research of mechanical vibration and dynamic load for horizontal worm screen centrifuge

在卧式螺旋卸料过滤离心机工作时会因物料分布不均而产生偏心载荷。该力的大小、位置、矢量方向都随时间不断变化,且离心机整机是一个较复杂的系统。因此,要准确计算偏心载荷引起的瞬态响应是一个难点。在ANSYS中使用APDL语言进行整机的参数化建模,运用COMBIN14单元模拟了轴承和减振器,对电机和机外壳等焊接件采用MASS21单元作等效处理;使用Newmark完全法进行瞬态动力学分析,首次计算得到了主轴的振动曲线以及离心机对安装基础的动载荷特性曲线。研究结果表明:采用有限元瞬态动力学分析方法可以获得与加料试车实验方法相一致的主轴振动速度曲线和离心机对安装基础的动载荷的极大值。解决了机械振动与动载荷长期以来依赖经验估算的问题,缩短了新产品的设计周期,降低了新机试制、试车的风险,也为离心机工作可靠性的研究奠定了基础。

Due to the unevenly distributed material, horizontal worm screen centrifuge usually produces eccentric load under its working conditions. The size, position and vector direction of the force change with time, and the whole centrifuge is a complex system. So it's difficult to calculate the transient response caused by eccentric load. A parametric model for whole machine is constructed by APDL language in ANSYS. The COMBIN14 element is adopted to simulate bearings and shock absorbers. Equivalent treatment for motor and wielding shell of whole machine is implemented by using MASS21 element. Newmark full method is used to do transient dynamic analysis, which for the first time calculates the characteristic curves of both spindle and dynamic load from centrifuge to the install base are calculated. The research results show that using transient dynamic finite element method to analysis mechanical vibration velocity curve and maximum dynamic load value from centrifuge to foundation, the same results as experimental data of trial run can be gotten. This method solves the calculation problem of mechanical vibration and dynamic load, which has long depended on empirical estimates, and shortens design cycle of new products. Besides, it reduces risks both of trial production and trial run, and it lays a foundation for research of operational reliability of this machine.