1、 INCH-POUND MIL-DTL-25427B 15 May 2009 SUPERSEDING MIL-C-25427A 16 Sept 1960 DETAIL SPECIFICATION COUPLING ASSEMBLY, HYDRAULIC, SELF SEALING, QUICK DISCONNECT, GENERAL SPECIFICATION FOR This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1
2、Scope. This specification covers the detailed requirements for aircraft hydraulic self sealing quick disconnect coupling for use in types I and II hydraulic systems (-65 F to +275 F temperature range) as defined by SAE-AS5440. 1.2 Classification. Hydraulic self-sealing, quick disconnect couplings ma
3、y be one of the following classes, as specified (see 6.2): Class 1000- 1000 pounds per square inch (psi) rated pressure furnished in 1.25 to 1.5 inch tube sizes (return lines). Class 3000- 3000 psi rated pressure furnished in 0.25 through 1 inch tube sizes (1.25 and 1.5 inch tube sizes are for retur
4、n lines only). Class 5000- 5000 psi rated pressure furnished in 0.25 to 1 inch tube sizes (1.25 and 1.5 inch tube sizes are for return lines only). 1.2.1 Part or identifying number (PIN). The part or identifying number to be used for couplings acquired to this specification is identified in the appl
5、icable specification sheet. Comments, suggestions, or questions on this document should be addressed to the Naval Air Systems Command, Attention: Code 4L8000B120-3, Highway 547, Lakehurst, NJ 08733-5100 or emailed to michael.sikoranavy.mil. Since contact information can change, you may want to verif
6、y the currency of this address information using the ASSIST online database at http:/assist.daps.dla.mil.AMSC N/A FSC 4730 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-25427B 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in thi
7、s section are specified in sections 3 and 4 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users
8、are cautioned that they must meet all specified requirements of documents cited in sections 3 and 4 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards and handbook form a part of thi
9、s document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. SPECIFICATIONS DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-PRF-5606 - Hydraulic Fluid, Petroleum Base; Aircraft, Missile, And Ordnance (Inactive for New
10、Design) MIL-A-8625 - Anodic Coatings for Aluminum and Aluminum Alloys MIL-DTL-25579 - Hose Assembly, Polytetrafluoroethylene, High temperature, Medium pressure MIL-P-25732 - Packing, Preformed, Petroleum Hydraulic Fluid Resistant, Limited Service at 275 F (135 C) (Inactive for New Design) MIL-PRF-83
11、282 - Hydraulic Fluid, Fire Resistant, Synthetic Hydrocarbon Base, Metric, NATO Code Number H-537 MIL-H-85800 - Hose Assemblies, Polytetrafluoroethylene, Aramid Fiber Reinforced 5000 and 8000 psi, General Specification for MIL-PRF-87257 - Hydraulic Fluid, Fire Resistant, Low Temperature, Synthetic H
12、ydrocarbon Base, Aircraft and Missile DEPARTMENT OF DEFENSE STANDARDS MIL-STD-129 - Marking For Shipment And Storage MIL-STD-130 - Identification Marking Of US Military Property MIL-STD-810 - Environmental Engineering Considerations and Laboratory Tests MS21344 - Fittings - Installation of Flared Tu
13、be, Straight Threaded Connectors, Design Standard For DEPARTMENT OF DEFENSE HANDBOOK MIL-HDBK-831 - Preparation of Test Reports (See supplement 1 for applicable specification sheets.) 2Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-25427B (C
14、opies of these documents are available online at http:/assist.daps.dla.mil/quicksearch/ or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.) 2.2.2 Non-Government publications. The following documents form a part of this document to the exten
15、t specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. SOCIETY OF AUTOMOTIVE ENGINEERS (SAE) INTERNATIONAL SAE-AMS2700 - Passivation of Corrosion Resistant Steels (DoD Adopted) SAE-AMS4965 - Titanium Alloy, Bars, Wire, Forgings
16、and Rings, 6Al-4V Solution Heat Treated and Aged (DoD Adopted) SAE-AMS5047 - Steel, Sheet and Strip, .08-0.13C, Aluminum Killed (SAE1010) Deep Forming Grade (DoD Adopted) SAE-AMS5085 - Steel, Strip, and Plate, 0.47-0.55C (SAE1050) Annealed (DoD Adopted) SAE-AMS5529 - Steel, Corrosion Resistant, Shee
17、t and Strip 17CR-7.1NI-1.1A1 Solution Heat Treated and Cold Rolled, Precipitation Hardenable 0.0015 to 0.050 Inch (0.038 to 1.27MM) Normal Thickness (DoD Adopted) SAE-AMS5643 - Steel, Corrosion Resistant, Bars, Wire, Forgings, Tubing and Rings, 16Cr-4Ni, 0.30Cb-4 Cu, Solution Heat Treated Precipitat
18、ion Hardenable (DoD Adopted) SAE-AMS5659 - Steel, Corrosion Resistant, Bars, Wire, Forgings, Rings, and Extrusions 15CR - 4.5NI - 0.30CB - 3.5CU Consumable Electrode Melted Solution Heat Treated, Precipitation Hardenable (DoD Adopted) SAE-AMS5678 - Steel, Corrosion Resistant, Wire, 17Cr-7.1 Ni-1.1 A
19、l, Cold Drawn, Precipitation Hardenable (DoD Adopted) SAE-AMS-P-83461 - Packing, Preformed, Petroleum Hydraulic Fluid Resistant, Improved Performance at 275 F (135 C) (DoD Adopted) SAE-AMS-QQ-A-225/6 -Aluminum Alloy, 2024, Bar, Rod, and Wire; Rolled, Drawn, Or Cold Finished (DoD Adopted) SAE-AMS-QQ-
20、A-225/9-Aluminum Alloy 7075, Bar, Rod, Wire, and Special Shapes; Rolled, Drawn or Cold Finished (DoD Adopted) SAE-AMS-QQ-P-416 - Plating, Cadmium (Electrodeposited) (DoD Adopted) SAE-AS603 - Hose, Hydraulic, Tubing and Fitting Assemblies, Impulse Testing of SAE-AS1339 - Hose Assembly, Polytetrafluor
21、oethylene, Metallic Reinforced 3000 psi, 400oF, Lightweight, Hydraulic and Pneumatic (DoD Adopted) SAE-AS8775 - Hydraulic System Components, Aircraft and Missiles, General Specification for (DoD Adopted) SAE-AS8791 - Hydraulic and Pneumatic Retainers (Back-up Rings), Polytetrafluoroethylene (PTFE) (
22、Resin) (DoD Adopted) 3Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-25427B (Copies of these documents are available online at http:/www.sae.org or from the Society of Automotive Engineers, 400 Commonwealth Drive, Warrendale, Pennsylvania 15
23、096.) AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM-D3951 - Commercial Packaging (Copies of these documents are available online at http:/www.astm.org or from the American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103.) AMERICAN NATIONAL STANDARDS INS
24、TITUTE (ANSI) ANSI-B46.1 - Surface Texture (Surface Roughness, Waviness, and Lay) (Copies of this document are available online at http:/www.ansi.org or from ANSI, 25 West 43rdStreet, New York, NY 10036-8002.) AMERICAN SOCIETY FOR QUALITY (ASQ) ANSI/ASQ-Z1.4 - Sampling Procedures and Tables For Insp
25、ection By Attributes (Copies of this document are available online at http:/www.asq.org or from the American Society for Quality, 611 East Wisconsin Avenue, Milwaukee, WI 53202.) 2.3 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of
26、 this document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 Specification sheets. The individual item requirements shall be
27、 as specified herein and in accordance with the applicable specification sheet or MS sheet. In the event of any conflict between the requirements of this specification and the specification sheet or MS sheet, the latter shall govern. 3.2 Qualification. The couplings furnished under this specificatio
28、n shall be products that are authorized by the qualifying activity for listing on the applicable qualified products list before contract award (4.5 and 6.4). 3.3 General specification. The requirements of SAE-AS8775 apply if it is necessary and if the requirements are not specified in this specifica
29、tion. 3.4 Materials and finish. The materials shall be as specified in table I. The selected materials shall be corrosion resistant metal or protected from corrosion and shall be compatible 4Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-254
30、27B with hydraulic fluids conforming to MIL-PRF-5606, MIL-PRF-83282, or MIL-PRF-87257. The finish requirements of the coupling shall be as specified in table I. 3.4.1 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be
31、used to the maximum extent possible, provided that the material meets or exceeds the operational and maintenance requirements, and promotes economically advantageous life cycle costs. TABLE I. Materials and finishes. Material Material Code Material specification Finish Note Aluminum alloy 2014/2024
32、D SAE-AMS-QQ-A-225/6 temper T351 Anodized per MIL-A-8625, type II, class 1 Dichromate sealed or Class 2, Nickel acetate seal For 1000 psi only Aluminum alloy 7075 W SAE-AMS-QQ-A-225/9 Temper T73 Anodized per MIL-A-8625, type II, class 2 dyed brown For 3000 psi Stainless steel 300 series 15-5 PH or 1
33、7-4PH S SAE-AMS5529, SAE-AMS5643, SAE-AMS5678 or SAE-AMS5659 Passivate per SAE-AMS2700 Carbon steel C SAE-AMS5085, or SAE-AMS5047 1/ Cadmium plated per SAE-AMS-QQ-P-416, type II, class 2 Titanium T SAE-AMS4965 None For 3000 and 5000 psi 1/ This document references cadmium plating. See 6.5 for inform
34、ation using cadmium. 3.5 Design and construction. The configuration, dimension, and the detail design and construction of the coupling shall conform to the applicable specification sheets or MS sheets. The objective of the design is obtaining smallest size and lightest weight possible commensurate w
35、ith meeting the performance requirements specified herein. When the two halves coupled, the coupling assembly shall permit fluid flow in intended direction in accordance with the rated flow and pressure drop specified in tables II. Flow shall not be blocked under surge conditions. 3.5.1 Temperature
36、range. Coupling shall be designed for operation with type II hydraulic fluid having the temperature range from -65 F to +275 F. 3.5.2 Sealing and fluid loss. When uncoupled, the couplings shall seal at the point of disconnection at the end of the disconnected lines and shall not permit external leak
37、age during any phase of coupling or uncoupling. Fluid loss (spillage) as specified in tables III is not 5Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-25427B considered external leakage. Both coupling halves shall seal fluid under low and h
38、igh operating pressures. 3.5.3 Seals. SAE-AMS-P-83461 packing, MIL-P-25732 packing, and SAE-AS8791 PTFE retainer shall be used which are compatible with MIL-PRF-5606, MIL-PRF-83282, or MIL-PRF-87257 hydraulic fluids. 3.5.4 Operation. The coupling shall be so designed that it can be coupled and uncou
39、pled with one hand without the use of tools. Coupling and uncoupling operations shall be possible with 60 psi static pressure applied to both halves of the coupling. Inadvertent uncoupling shall not occur under normal vibration environment of powered flight, dynamic loading of aircraft within flight
40、 and maneuvering envelopes, and during shocks associated catapult launch/arrested landing. It shall be possible to determine by visual inspection that the coupling is completely coupled and locked. In addition, couplings shall provide a touch indication for determining whether the coupling is locked
41、 or unlocked. Couplings shall not have any partially coupled unlocked positions in which the couplings can remain stable and permit fluid flow. Couplings shall be coupled with a single simple motion. TABLE II. Coupling assembly rated flow, surge flow, and pressure drop for all pressure classes. Dash
42、 No. Tube OD Rated flow Gal/min Surge flow Gal/min Pressure drop psi (max) -04 0.250 1.2 6 8 -06 0.375 3.5 17.5 8 -08 0.500 6.0 30 8 -10 0.625 10.5 52.5 8 -12 0.750 16 80 8 -16 1.000 29 87 8 -20 1.250 45 90 4 -24 1.500 60 120 4 6Provided by IHSNot for ResaleNo reproduction or networking permitted wi
43、thout license from IHS-,-,-MIL-DTL-25427B TABLE III. Air inclusion and fluid loss for all pressure classes. Air inclusion cm3 (in)3max Average fluid Loss per operating cycle (spillage) cm3 (in)3maxDash No. Tube OD 3000 psi 5000 psi 3000 psi 5000 psi -04 0.250 0.05 0.10(.006) 0.50 (.031) 0.05 (.003)
44、-06 0.375 0.12 0.20 (.012) 1.30 (.079) 0.10 (.006) -08 0.500 0.20 0.40 (.025) 2.20 (.134) 0.20 (.012) -10 0.625 0.50 0.60 (.037) 5.80 (.354) 0.30 (.018) -12 0.750 0.70 1.00 (.061) 8.20 (.500) 0.50 (.031) -16 1.000 0.90 1.75 (.107) 9.00 (.549) 1.00 (.061) -20 1.250 1.20 2.00 (.122) 11.80 (.720) 1.20
45、(.073) -24 1.500 1.20 2.50 (.153) 11.80 (.720) 1.50 (.092) 3.6 Interchangeability of bulkhead halve coupling. Bulkhead halve couplings (mounted on aircraft) shall be interchangeable as an assembly or individual coupling halves for same tube size and pressure class. It shall be designed not to interc
46、onnect coupling assembly or coupling halves of different tube sizes. Couplings of different pressure classes shall not be capable of cross coupling. This requirement does not apply to hose end couplings which shall be interchangeable regardless of pressure classes. 3.7 Performance. The self sealing
47、coupling furnished under this specification shall perform satisfactorily when conducting to the following performance requirements. 3.7.1 Envelope dimensions, weight, materials. Each coupling half shall conform to the applicable specified envelope dimensions, weight, materials, and finishes specifie
48、d in the applicable specification sheet. 3.7.2 Manual operation. Coupling halves shall be tested in accordance with the requirements specified in 4.8.2 with no evidence of coupling forces, leakage or spillage beyond the specified limits specified in table IV and table III respectively. Both coupling
49、 halves shall be installed in the systems capable of accommodating fluid displacement without pressure rise. 3.7.3 Immersion. The self sealing coupling contains nonmetallic parts and therefore shall be compatible with hydraulic fluid and show no leakage, damage or malfunction when tested as specified in 4.8.3. 3.7.4 Air inclusion. The air inclusion for all coupling halves shall be within specified
