Figure 9-3.—Typical fluid-pressurized reservoir.threaded openings for connecting fittings andcomponents. Figure 9-4 shows several componentsinstalled in lines leading to and from the reservoir;however, this may not be the case in actualinstallation. The air relief valve, bleeder valve, andsoon, may reinstalled directly on the reservoir.Because the reservoir is pressurized, it cannormally be installed at any altitude and stillmaintain a positive flow of fluid to the pump.Figure 9-4.—Air-pressurized reservoir.Some air-pressurized reservoirs also havedirect contact of fluid to gas. These reservoirs areinstalled in large systems and may be cylindricalor rectangular in shape. They contain an oil levelindicator, a pump inlet or suction line connection,a return line, a gas pressurization and ventingconnection, and a drain line connection or a drainplug. These reservoirs are pressurized by air fromthe ship’s service air system or nitrogen banks.These reservoirs are found on board aircraftcarriers and submarines.ACCUMULATORSAn accumulator is a pressure storage reservoirin which hydraulic fluid is stored under pressurefrom an external source. The storage of fluidunder pressure serves several purposes in hydraulicsystems.In some hydraulic systems it is necessary tomaintain the system pressure within a specificpressure range for long periods of time. It is verydifficult to maintain a closed system without someleakage, either external or internal. Even a smallleak can cause a decrease in pressure. By usingan accumulator, leakage can be compensated for9-3
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
