INFLUENCE OF HYDROABRASIVE WEAR OF IMPELLER BLADES ON THE HEAD OF A CENTRIFUGAL PUMP
Аннотация
The results of experiments on studying the nature of changes in the concentration and dispersion of solid suspended particles showed that the highest average monthly sediment concentration is 2.5..3.8 kg/m<sup>3</sup>, and sometimes in rainy weather the maximum water turbidity reaches 7 kg/m<sup>3</sup>. In the composition of solid mechanical impurities, a significant amount consists of particles with a grain size of 0.1-0.05 mm. Observations have established that particles larger than 0.01 mm at a low flow velocity in the supply channel and the water intake chamber of the pumping station were easily deposited in them. Siltation volumes at various stations ranged from 20 to 60%. As a result, the hydraulic resistance increased, which led to a decrease in the pump head. The wear of parts of centrifugal pumps under natural conditions was also studied, taking into account the dependence of wear on the characteristic dimensions and duration of their operation. The results of micrometer measurements of the working parts of the pumps showed that the blades of the impellers along the length and width wear out unevenly both in size and in shape. This is explained by the fact that when the hydroabrasive flow moves in the interblade space, the kinetic energy of solid particles and their local concentration increase due to an increase in the values of centrifugal and Coriolis forces along the radius of the impeller.