System analysis of internal and external impacts on overhaul repair frequency of vertical split casing pumps

Abstract

ALROSA is currently starting transition from surface to underground mining of kimberlite pipes. Underground mining promotes with various-nature rushes of water in underground openings. These inflows of water are finally collected in drain sumps of the main water-removal plant, and then are pumped out to ground surface by vertical split casing pumps. The practice shows that frequent overhaul repairs are typical of the domestic-manufacture split casing pumps operated in underground kimberlite mines. The overhaul repair frequency of the vertical split casing pumps is largely governed by the radial clearance between the inside faces of the gasket rings and the outside surfaces of the seal bands of the impellers. It is found that the dominant impact on the multifactor damage pattern of impeller sealers in vertical split casing pumps operated in underground kimberlite mines in Russia is exerted by hydro-abrasive wear, especially at the sites of corrosive filming. The integrated research finds out that the average service life between the overhaul repairs of the vertical split casing pumps in use in the underground kimberlite mines in Russia greatly depends on such external and internal impacts as the pump head, error-free running time of the balancing ring and concentration of mechanical impurities in mine water. The implemented regression analysis has yielded a prognostic model which allows a sufficiently reliable perspective forecast of average service life of the vertical split casing pumps between overhaul repairs for the underground kimberlite mines in Yakutia.