フレキシブル継手と剛体円板を用いたポンプ配管系の振動低減対策: 直線状配管を対象とした検討(機械力学,計測,自動制御)

A vibration reduction method that involves installing two flexible joints in series has been found to be useful for countermeasures against structure-borne sound in pump piping system. However, it has the practical difficulty that the pipe's vibration mode must be measured many times for determining the optimum location of flexible joints. Therefore, we newly propose the technique using two flexible joints and a rigid disk in order to improve the practicality of the previous method. In the present method, two flexible joints are first installed anywhere on the piping near the pump, and a rigid disk is then mounted on the piping between the pump and the flexible joint. Then, the pipe vibration can be easily reduced by just adjusting the location of the rigid disk without measuring the pipe's vibration mode. In this paper, the influence of underwater sound is neglected for simplify and the effectiveness of the present method in reducing vibration in straight-line piping is investigated analytically and experimentally. The results of the numerical analyses and experiments confirm that the present method is excellent in terms of usefulness and can achieve the vibration reduction effect comparable to the previous method.