UNDERWAY REPLENISHMENT NWP 4-01.4 - Historic Naval Ships ...

NWP 4-01.4J.3.2 NATO Coupling Modification. Modificationof the NATO coupling B-end is necessary to allow fittingthe pig catcher into the coupling. The modification,which adds three reliefs in the sealing ridge of the coupling’sface, is detailed in Figure J-5.J.3.3 Storage Facilities. A designated storagelocker should be provided for cool and dry storage ofthe pigs, hose crimper, pig catcher, and associated hardware.This locker should be able to screen most of thelight, since sustained exposure of the pigs to light (especiallyultraviolet) will cause chemical breakdown ofthe polyurethane foam material and result in flaking.J.3.4 Instruction Placard. An instruction placardshould be provided on each tanker that uses the pig system.It should list briefly the necessary operating instructionsexplained in paragraph J.2. The placardshould be of durable material with clear, legible writingand located at the astern refueling station. An exampleof the essential instructions that should appear on theplacard is shown in Figure J-6.J.4 MAINTENANCEJ.4.1 Inspection. The pig method of cleaning fuelhose uses simple, passive equipment that should give reliableperformance. To help ensure proper operation ofthe system, the following items should be given attention:1. The orifice located in the blowdown air supply lineshould be inspected once every 6 months. The orificeshould be checked for blockage by dirt or corrosionand cleaned or replaced as necessary.2. Pigs should be checked for flaking before use bybriskly rubbing the outside surface of the foammaterial and checking to see if foam particlescome loose. Flaking is undesirable because thedislodged particles could possibly block fuelsystem filters.3. When performing a blowdown operation, ensurethat the pressure gauge for the blowdown airsupply reads, at a minimum, 75 psig.4. Severe kinks should be removed from the hoseprior to commencing blowdown to permit unrestrictedflow of the pig.J.4.2 Troubleshooting. The following troubleshootingguidelines are remedies to some operating difficultiesthat may be encountered. Part numbers refer toFigures J-3 and J-4.MILL 3 RELIEFS, 5/8" x 3/8" (15.87 mm x 9.525 mm) DEEP, SPACED 120°IN SEALING RIDGE ON FACE OF NATO COUPLING B-END.120° TYPNATO COUPLING B-END5/8"(15.87 mm)3/8" (9.52 mm)SEALING RIDGEFigure J-5. Modification to NATO CouplingJ-6 ORIGINAL