离心泵中的汽蚀及其防护技术

介绍了离心泵汽蚀发生的机理、条件和特征,对液面压力、输送的介质、泵的安装高度及泵的结构对汽蚀的影响作了分析。通过改进泵吸入口叶轮到叶片入口附近的结构设计、采用诱导轮或双吸叶轮及合适的叶片进口正冲角、采用抗汽蚀材料及改善吸入管路的特性等方法予以消除或改善汽蚀。介绍了化学涂层、表面化学热处理、焊层与补焊、合金粉末喷涂、合金粉末喷焊和高速火焰喷涂等抗蚀技术的进展。

The Cavitation and Defending Techniques for Centrifugal Pump

The mechanism and conditions and characters of cavitation for centrifugal pump is introduced in this paper.The influences of cavitaion on liquid level pressure,medium,installation height and structure of the pump are analyzed.Cavitation can be eliminated or improved away by techiques such as modifying structure near pump suction entrance to impeller vanes entrance,using inducer or double-suction impeller,proper plus impact angle of the impeller vanes entrance, using anti-cavitation materials and improving the properties of the suction pipes. The anti-cavitation techniques' progresses such as chemical coating, surface chemical heat treatment, welding-layer and alloy powder spray-spread,alloy powder spray-welding and high-speed flame spray-spread are put forward.