Abstract
By a field hydraulic test using plastic pipes, and a simulation with a mathematical model based on the experimental results obtained, several factors associated with a pipeline system were classified.
For planning the introduction of a reducing pressure pipeline system, making use of a pressurereducing valve (automatic control valve), a combination system consisting of a “pressure reducing valve and safety valve” was found to be interception of hydrostatic pressure and water hammer pressure on the downstream side of the control valve.
On the other hand, for downstream side of the pipeline after passing through the control valve, a simple method did not always reduce the water hammer pressure sufficiently, because the rigidity of the pipe shell influenced the pressure generation rate.
Accordingly, it was classified that planning of facilities corresponding to the above situation, such as setting up a pressure-absorbing facility and a safety valve at the end of the pipeline system by considering the characteristics of the pipeline in each area is necessary.
In future, it will be necessary to make guidelines for installing countermeasure facilities against water hammer pressure by accumulation of detailed simulations.
