In order to further study the water hammer phenomenon in long distance gravity flow water conveyance pipelines, the industrial water supply project in Hinggan League Economic and Technological Development Zone was taken as the research object to study the influence of two-stage linear closing speed and combined valve closing schemes on the water hammer in the long distance gravity flow water conveyance pipeline, according to the basic principle of one-dimensional water hammer calculation. On this basis, the influence of total valve closing time on pipeline water hammer pressure was studied. The results indicate that the water hammer pressure along the pipeline increases with the increase of the opening of the rapid closing valve in the first stage; when the valves are closed at the same time, the water hammer pressure of the pipeline is large, and when the valves are closed alternately, the water hammer pressure is relatively small; prolonging the total valve closing time is conducive to reducing the water hammer pressure of the pipeline, and the optimal duration for two-stage linear closing of the project is 1,400 s. The study has a certain guiding value for the safe operation of long distance gravity flow water conveyance pipelines.