The pump station in recent years, there are some weak links in the field of water pump repair, work quality and work efficiency are inadequate, the main reason is, a large number of mechanical engineering university graduates within a few years of graduation, work and repair, and engineering students almost no formal training in the field of equipment repair repair; business in actual industrial production, by experienced engineer or without qualification of workers to handle, these people also lack of formal training in basic knowledge of all kinds of repair, so a high level of repair work can not repair the pump; project managers received a higher engineering education, generally only in self according to the instructions. Repair, and equipment designers generally lack of use experience, and get feedback from the user is less, so the development of the water pump repair was not reasonable. Therefore, Bo Yu company to help pump equipment operation, installation, pump maintenance workers and designers to better master pump equipment use and maintenance theory and methods, greater efficiency and a full team.

Single suction centrifugal pump impeller due to unilateral water, only a minus leakage ring; two suction centrifugal pump impeller due to its two side influent. So there are two minus leakage rings. Of large diameter, high lift is type centrifugal pump, especially a balance hole of the pump impeller back shroud, between in the wheel and the pump shell is also equipped with a leakage reduction ring; the multistage pump, before and after each impeller also are equipped with anti leakage ring. Its purpose is to decrease the amount of water leakage. Figure 2-12 shows three different forms of the minus leakage ring. Figure 2-12a is shown as a single ring, it has the advantages of simple structure, but because only installed in the pump shell, can only protect the impeller, and reducing the leakage effect in general; figure 2-12b shown is a double ring type, reducing the leakage ring on the top of the pump casing and impeller are respectively provided with a bearing grinding ring structure is more complex, anti leakage effect is good, both to protect the pump shell can also protect the impeller; figure 2-12c for double loop of the labyrinth type anti leakage ring, due to the joint surface into a polyline, water reflux resistance. Reducing leakage effect is best, but the structure is complex. Power station pump