新型自吸离心泵自吸结构设计与试验研究

针对传统大流量自吸离心泵自吸性能差、效率低等问题,设计了一种新型自吸结构的大流量自吸离心泵.将高压空气射流应用于泵的排气系统中,合理设计高压射流喷嘴的结构形式,对其主要尺寸进行计算,同时设计出与射流喷嘴配合工作的止回阀,选择气密性良好的球阀.提出新型轴联离合装置,通过皮带轮连接泵轴与空压机主轴,保证自吸完成后空气压缩机迅速脱离工作,并根据泵的排气要求以及国家标准,计算选取空气压缩机.对该新型大流量自吸离心泵机组自吸性能进行试验研究,记录各个高度下运行的自吸时间.试验结果表明:当自吸高度分别为5.3,6.0,7.0,8.1 m时,自吸时间依次为62,92,121,173 s,自吸时间均小于国家标准规定值,自吸性能优势十分明显,机组的效率显著提高.

Design and test of new self-priming structure for self-priming centrifugal pump

For traditional high flow self-priming centrifugal pumps are subject to poor self-priming performance and low efficiency, a large flow self-priming centrifugal pump with a new self-priming structure is designed. In the design, a high-pressure jet is involved into the gas exhaust system of the pump, then the structure of jet nozzle is designed carefully and reasonably, and their main dimensions are decided accordingly. Moreover, a check valve is designed as well for the nozzle, and a globe valve with good air tightness is chosen. A new coupling-clutch transmission device is put forward, in which the shafts of the pump and a compressor are connected with a pulley to ensure the compressor to be detached quick after the self-priming completion. A compressor is selected according to the requirement on the exhaust by the pump and relevant national technical standards. Experiments on the self-priming performance of the newly designed self-priming pump are carried out, and the priming times at different suction heights are recorded. The experimental results show that the self-priming times are 62, 92, 121 and 173 s, respectively, when the suction heights are 5.3, 6.0, 7.0 and 8.1 m. These self-priming times are less than those specified in relevant national technical standards. Thus, for the pump, its advantage in the self-priming performance is not only obvious, but the overall efficiency of the pump unit is also improved significantly.