The main objective of this work is to study hydraulic transient and its influence on pipes behaviour. The importance of fluid-structure interaction (FSI) and complexity of hydraulic systems are dependent, since structure reacts to movement of flow and consequently fluid response is generated by vibration of structure. Thus, 3D model based on Computational Fluid Dynamics (CFD) is used. Numerical model predictions are compared with experimental tests performed on a physical model adapted for this purpose. Solution obtained can provide a means for better understanding structural effects involved in hydraulic devices and in pipe systems.