7. Maintenance on cranes should be performedonly by formally qualified personnel, unless authorizedby an authorizing officer on a single case basis forunusual repairs.You must do all the maintenance requirementsaccording to the instructions provided on the applicableMRCs. If the MRCs do not exist for a particular pieceof equipment, your supervisor or you should instituteinterim maintenance according to the manufacturer’srecommendations.The following maintenance items should beincluded in the crane PMS package:l Lubricationl Safety inspectionl Lube oil maintenancel Wire ropel Brakesl Instrumentationl ElectricalFor more general information on cranemaintenance, repairs, and inspections, read NSTM,Chapter 589, “Cranes.”Your ship should have a copyof the manufacturer’s technical manual for in-depthindividualized information of your ship’s crane.DUMBWAITERSA dumbwaiter is a semiautomatic electro-mechanical hoist operating in a structural trunk. The carof a dumbwaiter is arranged to carry ship’s stores ofvarying weights and package sizes. Figure 8-10illustrates the parts and controlling mechanisms of adumbwaiter.You should inspect the dumbwaiter car and hoistevery 3 months. Check the condition of the load cable(it could be a chain or wire rope cable), motor brake,friction clutches, overtravel limit devices, door interlockcontrol switches, and safety devices. You must followthe manufacturer’s manual or the procedures specifiedby the PMS when making repairs. You are required tocomplete a PQS for this equipment. For more generalinformation, read NSTM, Chapter 572, “ShipboardStores and Provision Handling.”Figure 8-10.—Dumbwaiter.ESCALATORSOnly aircraft carriers have escalators aboard, andeach aircraft carrier has two escalators. Each is chaindriven by a horizontally mounted worm gear machine.An escalator can operate in either direction and isdesigned to operate at a speed of 120 feet per minute,carrying flight personnel at the rate of 44 persons perminute. For full details of this equipment, read NAVSEA0316-LP-020-7000, Shipboard Escalators (AircraftCarriers). You must complete the required PQS for thisequipment. When making repairs, follow the necessarysafety precautions and the procedures specified by themanufacturer’s manual or the PMS.SUMMARYThis chapter has provided you with some generalinformation on the maintenance and repair of auxiliarymachinery. For you to do your job properly, you mustbe totally familiar with each piece of machinery; you8-16
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business