Study on the Protective Measures for Pump-Stopping Water Hammer of Long Distance Pipeline Engineering

Long-distance water pipelines that operating jointly with multi-pump has the characteristics such as large flow and high lift,the sudden-stop will cause water hammer effects in the pipelines,which have huge damages to the system. In order to ensure the safe operation of water conveyance project,it is necessary to analyze the characteristics of water hammer and the corresponding protective measures of water hammer. Taking a water conveyance project as an example,combined with water hammer theory and characteristic line method,the mathematical model of the valve boundary,air valve boundary and pipeline were used to calculate and analyze the pump stopping water hammer of long-distance water pipelines respectively which used protective measures such as air valves,general check valves,slow butterfly valves or their combination. At last,the maximum head,the minimum head as well as the change rule of pump speed and flow relative value was obtained. By comparison,the study found that the operation using water hammer protection measures combined with air valve and the two phase of the butterfly valve could reduce the pipeline extreme pressure and ensure the safe operation of the pipeline and the water pump.