大流量低汽蚀余量高速泵在聚乙烯装置上的应用

Application of Large Flow Low NPSH High Speed Pump in Polyethylene Plant

聚乙烯装置的异丁烷溶液(LSR)循环泵流量大、扬程高、装置汽蚀余量低,适合采用低汽蚀余量的大功率高速泵。介绍了该大功率高速泵的主要技术特点,针对低汽蚀余量的要求,分别设计了等螺距和变螺距诱导轮,并进行了数值模拟分析和汽蚀性能试验。结果显示配置变螺距诱导轮泵的汽蚀比转速达到3 398,能够满足现场使用要求。对比高速泵和进口的BB5型多级泵,表明高速泵在运行可靠性、使用和维护及价格方面都有一定的优势。

LSR recycle pump is required with the features large flow, high head and low NPSH when it is used in polyethylene plant, so large power high speed pump with low NPSH is applicable. In this article, typical technical parameters of one kind of large power high speed pump were introduced. With respect to the requirement of low NPSH, equal pitch and varied pitch inducers were designed respectively, and then simulation analysis and test of NPSH performance were carried out. It was shown that by using varied pitch inducer the rotary speed may reach 3398 without NPSH, which meet the requirement in application. By comparing high speed pump and imported BB5 multi stage pump, it was shown high speed pump has several advantages in the aspects of reliability, maintenance and cost.