高压多级离心泵转子系统的不平衡响应特性  

Unbalance response characteristics of rotor system in high pressure multi-stage pump

作　　者：张德胜[1] 汪靖[1] 施卫东[1] 叶晓琰[1] 田海平[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,江苏镇江212013

出　　处：《排灌机械工程学报》2014年第1期17-22,共6页Journal of Drainage and Irrigation Machinery Engineering

基　　金："十二五"国家科技支撑计划项目(2012BAB17B02-4;2011BAF14B01);国家自然科学基金资助项目(51276083);江苏省优势学科建设项目

摘　　要：针对高压多级离心泵转子系统质量不平衡问题,采用有限元分析方法计算了水润滑轴承支撑的转子系统的模态,并对转子系统不平衡质量的位置和分布进行了分析和优化.数值计算结果表明,采用两端水润滑轴承支撑的高压多级泵转子系统,根据第一阶临界转速的判定原则证明其为稳定的刚性转子系统;在设计转速下,不平衡质量施加在转子不同位置时,泵入口端水润滑轴承节点振动幅度变化较大,其对不平衡敏感程度较高,而出口端水润滑轴承附近节点振幅变化较小,且前3级叶轮的剩余不平衡质量对轴系不平衡响应具有较大影响;通过优化组合叶轮和平衡盘的平衡精度等级,找到了两端轴承振动幅值较小的方案,当前两级叶轮采用G2.5级、其他叶轮和平衡盘采用G6.3级平衡精度时,泵进口端水润滑轴承节点的振动幅值明显降低,且泵出口端轴承节点的振幅变化较小,成功应用于高压多级离心泵的设计,满足了工程应用要求;在不同转速下,泵入口端水润滑轴承比出口端对不平衡响应更为敏感,建议入口端轴承采用更耐磨的材料.优化结果可为新型多级离心泵转子系统稳定运行提供理论依据和参考.In order to solve the rotating unbalance problem of the rotor in a high pressure multistage centrifugal pump,the modals of its rotor system supported by two water lubricated bearings were calculated by using FEM method,the mass unbalance location and distribution on the rotor were analyzed and optimized. The results show that this rotor system is rigid based on the 1st critical speed predicted. Under the design rotating speed,when a rotating unbalance is applied on the rotor at different positions,the vibration amplitude of the bearing in the suction chamber side exhibits substantial changes, indicating that bearing is very sensitive to unbalance; the vibration amplitude of the bearing in the discharge chamber side,however,has a little change and is insensitive to unbalance. Importantly,the residual unbalance mass distributed in the first three stages has a greater effect on shafting unbalance response. The case with smaller vibration amplitude in the two bearings has been secured by changing balance quality grades of the impellers and balance disk. When the balance quality grade of the first two-stage impellers is G2. 5,but the grade of the rest impellers and the balance disk is G6. 3,the bearing in the suction chamber side shows a significantly reduced vibration amplitude and the bearing in the discharge chamber side still keeps an acceptable small vibration amplitude. Under the other rotating speeds,the bearing in the suction chamber side can be even more sensitive to an unbalance mass than that in the discharge chamber side,thus it is suggested that the former should use a material with better wear-resistant property. These results can provide a theoretical basis and reference for stable operation of rotor system in high-pressure multistage centrifugal pumps.

关 键 词：多级泵 转子动力学 临界转速 平衡精度 不平衡响应 

分 类 号：TH311[机械工程—机械制造及自动化] S277.92[农业科学—农业水土工程]