Many valves are used in the piping and machinery system of the vessel as required by the fluid flow diagram. Valves are utilized on ships’ to regulate the flow of fluid in the pipelines and all valves are used and applied to all machinery for flow control. Although valves are an efficiency-reducing device as they reduce energy in fluid flow, their use is imperative in operations where limited flow is required. Valves regulate and control the pressure and flow of fluids of ships.