1、MILITARY S PE% IF ICAT ION COUPLING ASSEMBLLES y QUICK DISCONNECTy FUEL GRK-15/S32R AND GRU-13/E FSC 4930 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-38477C 47 M 7777906 024827 B MI MIL-C-38479C (USAI?) MIL-T-5624 MIL-N- 58 7 7 MIL-R-68 55
2、MIL-P-19834 MIL-H-26521 STANDADS Military MIL-STD-100 MIL-STD-105 MIL-STD-129 MIL- STD-130 MIL-STD-LU MIL-STD-2 76 MIL-STD-470 MIL-STD-808 MIL-STD-810 MIL-STD-831 MIL-STD-889 MIL-STD- 118 6 MS33786 Turbine Fuel, Aviation, Grades JP-4 and JP-5 Nozzle, Pressure Fuel Servicing, Locking, Type D-1, Nomin
3、al 2-1/2- inch Diame ter Rubber, Synthetic, Sheets, Strips, Molded or Extruded Shapes Plates, Identification, Metal Foil, Adhesive Backed Hose Assembly, Rubber, Fuel, Collapsible, Low Temperature with Reattachable Couplings Engineering Drawing Practices Sampling Procedures and Tables for Inspection
4、by Attributes Marking for Shipment and Storage Identification Marking of US Military Property Standards and Specifications, Order of Precedence for the Selection of Impregnation of Porous Nonferrous Metal Castings Maintainability Program Requirements (for Systems and Equipments) Finishes, Protective
5、, and Codes, for Finishing Schemes for Ground and Ground Support Equipment Environmental Test Methods Test Reports, Preparation of Dissimilar Metals Cushioning, Anchoring, Bracing, Blocking, and Waterproofing, with Appropriate Test Methods Fitting Installation, Flared Tube and Hose, Swivel (Copies o
6、f specifications, standards, drawings, and publications required by suppliers in connection with specific procurement functions should be obtained from the procuring activity or as directed by the contracting officer.) 2.2 Other publication. The following document form a part of this specifi- cation
7、 to the extent specified herein. Unless otherwise indicated, the issue in effect on date of invitation for bids or request for proposal shall apply. National Bureau of Standards Handbook H28 Screw-Thread Standards for Federal Services (Application for copies should be addressed to the Superintendent
8、 of Documents, Government Printing Office, Washington, DC 20402 .) 3. REQUIREMENTS 3.1 Preproduction. This specification makes provisions for preproduction testing. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-38477C 47 W 9777706 O248288 T
9、 W MIL-C-38479C (USAF) 3.2 Components. components: The coupling assembly shall consist of the following major Description See Requirement Coupling nipple 3.7.1 Coup 1 ing 3.7.2 Strainer 3.7.3 Gasket 3.7.4. Y 3.3 Selection of standards and specifications. Standards and specifications for necessary co
10、mmodities and services not specified herein shall be selected in accordance with MIL-STD-143. 3.4 Metals. Unless otherwise specified herein, the metals used shall be aluminum alloy or 300 series stainless steel. Metals shall be free from all defects and imperfections that might affect the serviceabi
11、lity of the finished coupling assembly and shall be appropriate for the environmental conditions specified herein. 3.4.1 Dissimilar metals. Unless protected against electrolytic corrosion, dissimilar metals shall not be used in intimate contact with each other. Dissimilar metals are defined in MIL-S
12、TD-889. An exception to the dissimilar metal requirement is the ball race insert. 3.4.2 impregnation of castings. Aluminum castings may be impregnated in accordance with MIL-STD-276 to prevent minor weeping. 3.5 Design and construction. capability, a strainer, and a quick disconnect for inspection o
13、f the strainer, all designed and constructed to meet the performance requirements of this specification. The coupling assembly shall withstand the stresses, impacts, vibrations, and other conditions incident to shipping, storage, installation, and service. The coupling assembly shall have a swivel 3
14、.5.1 Reliability. The coupling assembly shall have a mean-cycles-between- failure (MCBF) of not less than 100 cycles at 0.9 confidence. (See 6.3.1, 6.3.2, and 6.3.3.) 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-38479C 47 W 7777706 0248289
15、 II mi MIL-C-3847 9C (USAF) 3.5.2 Maintainability. The coupling assembly shall be so designed and con- structed that gaskets, seals, and the balls for the swivel feature can be readily replaced using only common handtools. The coupling assembly shall be designed and constructed in accordance with th
16、e design guidelines of MIL- STD-470 S paragraph tit led Es tab 1 ish Maintainab il ity Des ign Criteria. 3.5.3 Foolproofness. Where improper installation of an item could cause malfunctioning of that item or the system in which it is installed, an unsymmetrical mounting means shall be provided. This
17、 mounting shall be so designed that the item can only be installed in its proper operating position. 3.5.4 Safety features. safe operation with respect to the aircraft, fuel servicing equipment, and personnel operating and handling the assembly. The design shall not incorporate parts, appurtenances,
18、 handles, projections, cables, et cetera, which could hang on objects or become damaged by dropping or by dragging along a concrete ramp, or which could result in injury to personnel operating and maintaining the assembly, or cause the coupling assembly to be inadvertently disconnected. An unsafe fe
19、ature shall be cause for rejection. The coupling assembly shaQ be designed for inherent 3.6 Perf ormance 3.6.1 Environmental conditions. The coupling assembly shall be capable of operating under and withstanding the following environmental conditions: 3.6.1.1 Temperature ranges 3.6.1.1.1 Operating t
20、emperatures. The coupling assembly shall be capable of performing as specified herein in ambient temperatures between -65O and 3.1300F. 3.6.1.1.2 Storage temperatures. The coupling assembly shall not be damaged by storage in ambient temperatures from -8OO to f160F for not less than 50 hours. 3.6.1.2
21、 Humidity. or storage in any relative humidity up to and including 100 percent, including conditions wherein condensation takes place in the form of water or frost. The coupling assembly shall not be damaged by operation 3.6.1.3 Fungus. moist fungus growth. such as encountered in tropical and subtro
22、pical climates. The coupling assembly shall not be damaged by exposure to 3.6.1.4 Sand and dust. ation or storage in an atmosphere containing airborne sand and dust particles such as encountered in normal and desert operations. The coupling assembly shall not be damaged by Oper- 4 x - _- 4“ i I, e P
23、rovided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-38479C (USAF) 3.6.1.5 Salt atmosphere. operation or storage in an atmosphere containing salt-laden moisture as encountered near bodies of salt water and in transportation on shipboard. The coupling
24、 assembly shall not be damaged by 3.6.2 Fuel resistance. deteriorating effects or any condition which does not permit satisfactory operation when in contact with types I and III standard test fluids conforming The coupling assembly shall be capable of withstanding to TT-S-735. 3.6.3 Angular movement
25、. rotation (one end relative to the other) when subjected to internal pressure of O to 150 psig. The breakaway torque for rotation shall not exceed 20 pound-feet, after the coupling assembly has been submerged in types I and III standard test fluids as specified in 4.5.13, but with no internal press
26、ure. The coupling assembly shall be capable of 360-degree 3.6.4 Drag resistance. The coupling assembly shall withstand being dragged on a concrete floor and shall not be damaged, unlocked, or disconnected. No part of the complete coupling assembly shall break loose or disassemble. 3.6.5 Drop resista
27、nce. The coupling assembly shall withstand being dropped from different random altitudes on a concrete floor, when one end is attached to a 3- or 4-inch-diameter hose as applicable, and shall not be damaged, unlocked, or disconnected. No part of the complete coupling assembly shall break loose or di
28、sassemble. 3.6.6 Functional strength. The coupling assembly shall be capable of withstanding a 90-pound force applied at a 45-degree angle to its axis and shall not be damaged or leak as a result of this force. a 3.6.7 Pressure ratings. an internal working pressure of 150 psig and momentary internal
29、 surge pressures up to 250 psig. The coupling assembly shall be capable of withstanding 3.6.8 Pressure loss. The pressure loss across the coupling assembly shall not exceed the following values when using grade JP-4 fuel conforming to MIL-T-5624 with a specific gravity of 0.76 or greater, a fuel tem
30、perature of 70 +lOF, and at the stated flow rates: a. GRK-l5/S32R coupling assembly (3-inch inlet) : (1) 13 psi - With strainer in fueling position, flow rate 600 gpm in fueling direction (see figure 1) Without strainer, flow rate of 600 gpm in fueling direction de fueling direct ion (2) (3) 3.3 psi
31、 - With strainer in defueling position, flow rate 250 gpm in 1.5 psi - 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-38477C 47 7777706 0248273 T I MIL-C-38479G (USA?) -3 drawings showing both extreme pos it ions of the integral locking devi
32、ce in proper relationship to the coupling assembly i. Internal seal .material properties. 4.5.2 Pressure proof test. The coupling assembly shall be pressurized internally to 150 psig with dry air or nitrogen and then completely submerged into a water bath to detect leakage and porosity by visual mea
33、ns. Any distortion or leakage resulting from this test shall constitute a failure and shall be cause for rejection. 4.5.3. Weight. The weight shall be within the weight requirement specified in 3.10. The coupling assembly shall be weighed and the weight recorded. 4.5.4 Drag resistance test. 4-inch d
34、iameter hose, as applicable, and dragged on a concrete floor. The coupling assembly shall be slowly rotated during this dragging so that each 6-degree segment travels a minimum of 10 feet against the concrete floor. There shall be no evidence of damage to the coupling, it shall not unlock or disconn
35、ect, nor shall any part of the coupling assembly break loose or disassemble. 4.5.5 Drop resistance lest. The coupling shall be connected to a minimum 10-foot length of 3- or 4-inch-diameter h.ose, as applicable, conforming to MIL-H-26521. With the free end of the hose remaining fixed at ground level
36、, the coupling shall be elevated 6 feet above a concrete surface and allowed to fall freely on that surface. This procedure shall be conducted six times so that the coupling strikes the concrete floor in different random attitudes. Upon completion of the sixth drop, the coupling shall be disassemble
37、d and assembled without difficulty. A matching 1/4-inch-thick aluminum-alloy flange shall be bolted to the coupling-strainer assembly prior to initiation of the drop resistance test, Inability to assemble or disassemble the coupling as specified in 4.5.6.1 and 4.5.6.2, .inadvertent unlocking or disc
38、onnecting of the assembly, or any disassembly of coupling components (such as snap rings, metal bands, flat washers, et cetera) shall constitute a failure and The coupling shall be connected to a 3- or be cause for rejection. 4.5.6 Endurance tests 4.5.6.1 Dry. The coupling assembly shall be connecte
39、d and disconnected one hundred times, including removal and replacement of the strainer, when 15 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-38Y79C i.19 H 9997706 02i.1830L 7 M MIL-C-38479C (USAF) all the components are in a dry condition.
40、These connections and dis- connections shall be accomplished by one person while the coupling assembly is connected to a 6-foot or longer 3- or 4-inch diameter hose, as applicable, conforming to MIL-H-26521 and a pressure fuel servicing nozzle conforming to MIL-N-5877 without the use of additional e
41、quipment or facilities. A record of the difficulties experienced in connecting and disconnecting the coupling assembly shall be included in the test report. No malfunction or undue wear shall result from this test. 4.5.6.2 K. The test specified in 4.5.6.1 shall be repeated, except the coupling assem
42、bly shall be connected and disconnected 250 times and shall have had grade JP-4 fuel conforming to MIL-T-5624 flowing through the coupler or shall have been pressurized with grade JP-4 fuel in a static internal soak for not less than 6 hours prior to start of the test. A fuel pressure of 150 psig sh
43、all be applied each time a connection has been accomplished. Any malfunction, undue wear, leakage, difficulties encountered in the operation of the coupling,or the inability of the coupling to meet 3.6.9 constitutes a failure. 4.5.7 Angular movement test. The coupling assembly shall be installed in
44、a test setup as shown on figure 3. The breakaway torque shall be measured and shall not exceed 20 pound-feet both before and after fuel is introduced, but before the 25-pound force is applied and without internal pressure. The coupling assembly shall be rotated one end relative to the other 100 cloc
45、kwise revolutions and 100 counterclockwise revolutions while an internal fuel pressure of 60 psig is applied. At the completion of the 200 rotations, the coupling shall be subjected to the leakage test specified in 4.5.10, which shall be successfully accomplished. 4.5.8 Functional test. A special ad
46、apter incorporating 1-inch internal -nominal pipe threads designed to fasten to the nozzle end of the coupling nipple shall be installed in a fixture 7 feet above ground level. This adapter shall be so mounted that when the coupling assembly is attached, the horizontal centerline of the coupling ass
47、embly will be parallel to the plane of the ground. The coupling assembly shall be solely supported by the attachment at the nozzle end of the coupling assembly. Fifteen feet of 3- or 4-inch diameter hose, as applicable, conforming to MIL-H-26521 shall be attached to the threaded end of the coupling
48、assembly. The hose and coupling assembly shall be filled with grade JP-4 fuel conforming to MIL-T-5624, and the inlet of the hose shall be plugged or capped and placed at ground level. The hose and coupling assembly shall then be pressurized to 150 psig for 5 minutes by means of a hydraulic pump or
49、similar device through a connection or port at the inlet to the adapter. In addition, the coupling assembly shall be subjected to five surge pressures of 250 psig for periods of 5 seconds each. 16 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I MIL-C-3847% (USAI?) 1 U a, CA u c a, E a, 3 8 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,
