Scientific Journal of KubSAU

The calculation of pumping equipment and piping network parameters is presented. The method of cutting impeller pump diameter for optimal performance of pump unit with piping system on efficiency value is shown. The case of operating the distribution network and pumping station with three pump units D1250-25 is considered. Procedure of construction of loss-of-head curves in pipes, determination of the actual operating parameters of a single pump unit, selection of pump impeller diameter for essentials is indicated. Four points for graphing such curves are presented. According to the first point the whole network is divided into sections with suction, pressure main pipelines and pipelines with changing water flow compared with the previous ones. The second point involves definition of the electrical resistivity of each site. The resistance of network analyzer is determined in the third point, the loss-of -head of the whole network is determined in the fourth point. The article presents the scheme of pumping station with three pump units connected in parallel and a distribution network (Figure1), loss-of-head curves in pipes regardless the number of working pumps (Figure 2), the order of constructing three loss-of-head curves with operating one, two and three pumps with normal and cut pump impeller diameter (Figure 3 ), the order of determination of the actual parameters of pump work characteristics according to combined characteristics of normal and cut pump impeller diameter ( Figure 4) In conclusion, it is stated that the question of proper definition of actual parameters of pumps and the support of these parameters in optimal mode remains open due to the lack of proper methods of constructing loss-of-head curves pipeline. Every similar calculation is preliminary and should be carried out in field conditions