滚轮和型筒表面形貌对卧式离心铸造机振动性能的影响

Influences of surface roughness of rollers and mould on vibration characteristics of a roller-supporting horizontal centrifugal casting machine

滚轮支承卧式炉管离心铸造机型筒的振动对炉管最终质量有较大影响,而滚轮与型筒外表面形貌是引起铸造型筒振动的主要因素之一.利用自相关函数法模拟了滚轮和型筒的随机表面形貌,建立了由此表面形貌引起的对型筒转子激励力的计算模型;再应用传递矩阵法,构建了能够在考虑支承滚轮与型筒表面形貌的情况下,对型筒振动性能进行计算的方法,并进行算例分析,研究了表面粗糙度对振动性能的影响规律.结果表明:表面形貌引起的激励力以及节点最大振幅随粗糙度的增大近似线性增大;粗糙度不同时,幅频响应中发生较大振幅的转速基本一致;在同一转速下,相同时刻转子的形态相似,但振幅随粗糙度的变化而变化;型筒的中心运动轨迹范围随粗糙度的增大而增大.

Vibration of the mould of a roller-supporting horizontal centrifugal casting machine for furnace tubes strongly influences the final quality of the products,and the surface roughness of rollers and mould is an important source for mould rotor vibration.With autocorrelation function,the random surface topographies of rollers and mould are simulated.The approach to determine the excited forces caused by surface roughness is established.With transfer matrix method,the influences of roughness on the vibration characteristics are calculated and analyzed.The results show that the maximum excited force and maximum amplitude caused by the surface topography increase with roughness approximately linearly,under the same rotational speed and different roughness,the shapes of the mould rotor at the same time are similar but the vibration amplitudes changes,and the range of the mould center increases with the value of roughness increases.