1、SAE Technical Standards Board Rules provide that: This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom
2、, is the sole responsibility of the user.SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.Copyright 2001 Society of Automotive Engineers, Inc.All rights reserved. Printed in U.S.A.
3、TO PLACE A DOCUMENT ORDER: (724) 776-4970 FAX: (724) 776-0790 SAE WEB ADDRESS: http:/www.sae.org400 Commonwealth Drive, Warrendale, PA 15096-0001AEROSPACE STANDARDAS4875Issued 1995-05Reaffirmed 2001-12Fittings, Straight Threaded Boss or Flanged, Fluid Connection1. SCOPE:1.1 Scope:This SAE Aerospace
4、Standard (AS) establishes the requirements for straight threaded boss or flanged fluid connection fittings (see Section 6) for use in all types of fluid systems.1.2 Classification:Fittings shall be furnished in the types and styles designated by the applicable AN, AS, MS, NAS, or other engineering s
5、tandard drawings. This specification is the same as MIL-F-5509 as applicable to straight threaded boss or flanged fittings except for updated materials and process specifications and industry coordinated general improvements. It is intended to serve as a procurement specification for the fittings de
6、scribed herein and in Section 6.2. REFERENCES:2.1 Applicable Documents:The following publications form a part of this specification to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date of
7、 the purchase order. In the event of conflict between the text of this specification and references cited herein, the text of this specification takes precedence. Nothing in this specification, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.2.1.1 SA
8、E Publications: Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.AMS 2486 Conversion Coating of Titanium Alloys, Fluoride Phosphate TypeAMS 2488 Anodic Treatment, Titanium and Titanium AlloysAMS 4112 Aluminum Alloy Bars, Rods, and Wire, Rolled, Drawn, or Cold Finished 4.4Cu - 1.
9、5Mg - 0.60Mn (2024-T6)Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE AS4875 - 2 -2.1.1 (Continued):AMS 4124 Bars, Rods, and Wire, Rolled, Drawn or Cold Finished, 5.62N 2.5Mg 1.6Cu 0.23CrAMS 4134 A
10、luminum Alloy Die Forgings 4.4Cu - 0.85Si - 0.80Mn - 0.50Mg (2014-T4) Solution Heat TreatedAMS 4141 Forgings, Die, 5.6Zn - 2.6Mg - 7.6Cu - 0.23Cr, Solution and Precipitation Heat TreatedAMS 4928 Titanium Alloy Bars and Forgings, 6Al-4V, Annealed, 120,000 psi (827 MPa) YieldAMS 5639 Bars, Wire, Forgi
11、ngs, Tubing and Rings, 19Cr 10Ni Solution Heat TreatedAMS 5645 Bars, Forging, Tubing and Rings, 18Cr 10Ni 0.40Ti Solution Heat TreatedAMS 5646 Bars, Forgings, Tubing and Rings, 18Cr 11Ni 0.60 (Cr + Ta), Solution Heat TreatedAMS 5648 Bars, Forgings, Tubing and Rings, 17Cr 12Ni 2.5Mo, Solution Heat Tr
12、eatedAMS 6370 Steel Bars, Forgings and Rings, 0.95Cr 0.20Mo (0.28-0.30C)AMS 6382 Steel Bars, Forgings and Rings, 0.95Cr 0.20Mo (0.38-0.43C)AS478 Identification Marking MethodsAS930 Fitting End - Straight Thread Boss ConnectionAS1376 Alternate Dimensions, Center Body Section, Shape Fluid Fitting, Des
13、ign StandardAS4395 Fitting End - Flared Tube Connection, Design StandardAS4396 Fitting End - Bulkhead Flared Tube Connection, Design StandardARP4784 Performance and Evaluation Criteria, Surface Defects, Requirements for2.1.2 U.S. Government Publications: Available from DODSSP, Subscription Services
14、Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094.P-C-437 Cleaning Compound, High Pressure (Steam) CleanerQQ-A-225/6 Aluminum Alloy Bar, Rod, and Wire; Rolled, Drawn, or Cold Finished, 2024QQ-A-225/9 Aluminum Alloy Bar, Rod, Wire, and Special Shapes; Rolled, Drawn, or Cold Finished,
15、 7075QQ-A-367 Aluminum Alloy ForgingsQQ-P-35 Passivation Treatments for Corrosion-Resisting SteelQQ-P-416 Plating, Cadmium (Electro-deposited)QQ-S-763 Steel Bars, Wire, Shapes and Forgings, Corrosion-ResistingMIL-S-5626 Steel: Chrome Molybdenum (4140) Bars, Rods and Forging Stock (For Aircraft Appli
16、cations)MIL-H-6083 Hydraulic Fluid, Petroleum Base, For Preservation and OperationMIL-H-6088 Heat Treatment of Aluminum AlloysMIL-S-6758 Steel, Chrome-Molybdenum (4130) Bars and Reforging Stock (Aircraft Quality)MIL-H-6875 Heat Treatment of Steels (Aerospace Practice, Process For)MIL-A-8625 Anodic C
17、oatings, for Aluminum and Aluminum AlloysCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE AS4875 - 3 -2.1.2 (Continued):MIL-S-8879 Screw Threads, Controlled Radius Root With Increased Minor Diameter
18、: General Specification ForMIL-H-46170 Hydraulic Fluid, Rust Inhibited, Fire Resistant Synthetic Hydrocarbon BaseANA Bulletin No. 431 Air Force-Navy Aeronautical Bulletin Fittings, Flared, Classification of Defects ofFED-STD-595 Colors Used in Government ProcurementMIL-STD-105 Sampling Procedures an
19、d Tables for Inspection by AttributesMS21947 Fitting End - Bolt Cluster Fitting Single Port Through - FlareMS24385 Fitting End, Flared Tube Connection, Precision Type, Standard DimensionsMS24386 Fitting End, Bulkhead Flared Tube Connection, Precision Type, Standard DimensionsMS33649 Bosses Fluid Con
20、nection, Internal Straight ThreadMS33656 Fitting End, Standard Dimensions for Flared Tube Connection and Gasket SealMS33657 Fitting End, Standard Dimensions for Bulkhead Flared Tube Connection2.1.3 ANSI Publications: Available from ANSI, 11 West 42nd Street, New York, NY 10036-8002.ANSI/ASME B46.1 S
21、urface Texture (Surface Roughness, Waviness, and Lay)2.1.4 ASTM Publications: Available from ASTM, 1916 Race Street, Philadelphia, PA 19103-1187.ASTM A 108 Steel Bars, Carbon, Cold-finished, Standard QualityASTM A 370 Steel Products, Mechanical Testing of3. TECHNICAL REQUIREMENTS:3.1 Material:Fittin
22、gs shall be fabricated of materials listed in Table 1 or as specified on the applicable part standard drawing.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE AS4875 - 4 -TABLE 1 - MaterialsCopyrigh
23、t SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE AS4875 - 5 -3.1.2 Heat Treatment:3.1.2.1 Aluminum Alloy: Aluminum alloy fittings and nuts shall be supplied in the final temper as shown in Table 1. When fit
24、ting material is purchased in other than the final temper, the heat treatment shall be in accordance with MIL-H-6088.3.1.2.2 Steel: When additional processing is required to comply with the hardness requirements of 3.1.4, the heat treatment shall be in accordance with MIL-H-6875.3.1.3 Additional Phy
25、sical Properties: Unless otherwise specified on the applicable drawings, the hardness of the finished carbon steel parts with plating removed shall be 92 HRB to 31 HRC. For carbon steel fittings below a hardness of 20 HRC, hardness tests shall be made using the Rockwell B scale, in which case the ha
26、rdness shall be within the range of 92 to 99 HRB.3.2 Design and Fabrication:The design and fabrication of the fittings shall be in accordance with the applicable drawings. The fitting ends and boss connections shall be in accordance with AS930, AS4395, AS4396, MS21947, MS24385, MS24386, MS33583, MS3
27、3649, or MS33657 as applicable. Dimensional requirements are applicable after heat treatment and protective finishing. The center body section of shape fittings machined from bar or oversized forgings shall conform to AS1376.3.2.1 Shape and Form Restrictions: Abrupt reductions of section shall be av
28、oided. Small external sections adjoining relatively heavy body sections shall transition into the heavier sections by means of ample fillets.3.2.2 Passages:3.2.2.1 Drill Offset: On straight fittings where the fluid passage is drilled from each end, the offset between the drilled holes at the meeting
29、 point of the drills shall not exceed .015 in. It shall be possible to pass through the fluid passage a ball whose diameter is .020 less than the minimum diameter specified for the passage. This does not mean that the drilled passage may be smaller than that required by the detail drawings.3.2.2.2 C
30、ross Section at Fluid Path Junction: On shape fittings, the cross-sectional area at the junction of fluid passages shall be such that it shall be possible to pass through the fitting from end to end, a ball whose diameter is not less than .7 times the minimum diameter specified for the smaller passa
31、ge.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE AS4875 - 6 -3.2.3 Threads: Straight threads shall be of unified form and shall conform to MIL-S-8879 unless otherwise specified. Steel, corrosion-
32、resistant steel, and aluminum alloy threads may be cut, ground, or rolled (see 3.2.3.1). Copper alloy threads shall be cut or ground only.3.2.3.1 Rolled External Threads: Laps and seams, whose depths are within the limits of Table 2, are acceptable on the crest, and the nonpressure thread flank abov
33、e the pitch diameter. Laps and seams are not acceptable on any part of the pressure thread flank, in the thread root, or on the nonpressure thread flank extending from above to below the pitch diameter (see Figure 1). Stress cracks are unacceptable.3.3 Finish:3.3.1 Aluminum Alloy Fittings: Aluminum
34、alloy fittings, sleeves, and nuts shall be anodized in accordance with MIL-A-8625, Type II, Class 2, dyed blue or brown as applicable (see 3.4.4) and shall be duplex sealed.TABLE 2 - Depth of Laps, Seams, Surface Irregularities,and Discontinuities in Rolled ThreadsFIGURE 1 - Laps and Surface Irregul
35、arities in ThreadsCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE AS4875 - 7 -3.3.2 Carbon Steel Fittings: Carbon steel fittings, sleeves, and nuts shall be cadmium plated in accordance with QQ-P-4
36、16, Type II, Class 2, dyed black (see 3.4.4). All such carbon steel fittings, sleeves, and nuts shall be dipped in oil conforming to MIL-H-6083 or MIL-H-46170. Fluid passage holes, other openings, and internal threads shall not be subject to a plating thickness requirement and may exhibit bare areas
37、 provided that they are protected with a light film of oil.3.3.3 Corrosion-Resistant Steel Fittings: Corrosion-resistant steel fittings, nuts, and sleeves shall be passivated per QQ-P-35, Type VI or VII.3.3.4 Titanium Alloy Fittings: Titanium alloy fittings and nuts shall be anodized per AMS 2488 Ty
38、pe 2 or shall be fluoride phosphated coated per AMS 2486, except that a pretreatment, a modification of the fluoride treatment, or a post treatment shall be applied so that the final color of the fittings shall be similar to colors 36076 through 36176 per FED-STD-595 (see 3.4.4).3.4 Identification o
39、f Product:All fittings, nuts, and sleeves shall be marked in accordance with the following instructions. The marking shall be applied per AS478 as specified on the applicable drawing in a location not detrimental to the performance of the fitting and not detrimental to the corrosion protection of th
40、e fitting. When items cannot be physically marked because of lack of space or because marking would have a deleterious effect, the package shall provide the identification per 5.4.3.4.1 Manufacturers Identification: Unless otherwise specified, all fittings and nuts shall be marked with the manufactu
41、rers name, CAGE code or trademark and the letters AN, MS, AS, or NAS as applicable.3.4.2 Material Identification: Fittings and nuts shall be marked with the material code letter as shown in Table 1.3.4.3 Marking for Part Number and Size: A numerical size code equivalent to the nominal tube size in .
42、062 in increments is optional. All fittings and nuts larger than 06 fitting size code except cap assemblies, shall be marked with the basic part number, exclusive of size. Marking of part numbers on sleeves is optional. Fitting assemblies with assembled nuts shall be marked as above on the fitting b
43、ody, but assembled nuts that have their own part number identification are acceptable. Fittings previously manufactured to AN, AS, MS, or NAS standards that meet all other requirements of this document and the applicable part standards may retain their identification in addition to the previous requ
44、irements.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE AS4875 - 8 -3.4.4 Color Identification: In addition to the markings specified, the fittings, nuts, and sleeves shall be identified by the fo
45、llowing colors:a. Aluminum alloys 2014 and 2024: Blue (see 3.3.1)b. Aluminum alloy 7075: Brown (see 3.3.1)c. Steel: Black (see 3.3.2)d. Corrosion-resistant steel: Nonee. Titanium alloy: Gray (see 3.3.5)3.5 Workmanship:Machined surfaces of fittings, sleeves, and nuts shall be as specified on the appl
46、icable drawings. Unmachined surfaces, such as forged surfaces and bar stock flats, shall be free from blisters, fins, folds, seams, laps, cracks, segregations, spongy areas, or other defects as specified in ARP4784. Surface defects may be explored by suitable etching and if they can be removed so th
47、at they do not appear on re-etching and the required section thickness can be maintained, they shall not be cause for rejection. The surface texture of unmachined surfaces, except forging parting lines, shall be 250 in Ra per ANSI/ASME B46.1. The surface texture of forging parting planes shall be 50
48、0 in Ra per ANSI/ASME B46.1.4. QUALITY ASSURANCE PROVISIONS:4.1 Responsibility for Inspection:Unless otherwise specified in the contract or purchase order, the supplier is responsible for the performance of all inspection and test requirements as specified herein. Except as otherwise specified, the
49、supplier may utilize their own facilities or any commercial laboratory acceptable to the purchaser for the performance of the inspection and test requirement. The purchaser reserves the right to perform any of the inspections and tests set forth in this document, whenever such inspections and tests are deemed necessary to assure that supplies and services conform to prescribed requirements.4.2 Inspection Lot:A lot shall consist o
