DUPLICATION OF PUMPING MAIN

Abstract

Water supply involves a large amount of money. About 70 - 75% of the total cost of water supply system goes to the distribution system. As the diameter of the pumping main increases, the cost of water supply also increases. So proper selection of the size of pumping main is extremely important for reducing the cost of water supply system. Pump size is largely dependent on the diameter of the pumping main. If the size of pumping main is too small, the cost of pumping main will be less but the friction la Qd loss in the main will be more which will call for a higher horse power pump and result in increased power consumption. Similarlyhtight of overhead tank depends upon the diameter of pumping main. A smaller diameter of pumping main will cause more friction head loss and thereby increase the height of overhead tank and ultimately increase the cost of the scheme. So several designers have developed techniques for the optimization of pumping main and pipe net work by taking into account cost parameters. In the present discussion optimization of pumping main has been done considering the cost parameters such as cost of pumping main and cost of power, taking different discharges. It is also assumed that the discharge increases with respect to time to compensate the future population growth. So in the future a situation arises such that the total required discharge cannot be conveyed by the pumping main iv which has initially laid. To overcome this condition one more pumping main has to be installed in a particular year in future. Our discussion is to determine the most economical diameter of the pumping mains and time of installation of the duplicate pumping main. **