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 entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising theref
2、rom, 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 2010 SAE International All rights reserved. No part of this publication ma
3、y be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA)
4、Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AS7472AAEROSPACESTANDARDAS7472A Issued 1991-01 Reaffirmed 2006-05 Revised 2010-06Superseding AS747
5、2 (R) Bolts and Screws, Steel, Corrosion Resistant 125 000 psi Tensile Strength Roll Threaded FSC 5306 RATIONALEUpdate para 3.7 by adding “two to” three threads in agreement with NASM1312-8 test methodology. Added para 4.2, completely revised para 4.4.4 and Tables 4, 5, 6 and 7 by removing sampling
6、in accordance with MIL-STD-105 (AQL) and replacing with accept on “zero”. General updating for SAE requirements for obsolete specifications and standards.1. SCOPE 1.1 Type This procurement specification covers aircraft quality bolts and screws made from a corrosion resistant austenitic iron base all
7、oy of the type identified as SAE 30302 and of 125 000 psi tensile strength at room temperature. 1.2 Application Primarily for aerospace propulsion system applications where a good corrosion resistance and moderate strength is required.1.3 Safety - Hazardous Materials While the materials, methods, ap
8、plications, and processes described or referenced in this specification may involve the use of hazardous materials, this specification does not address the hazards which may be involved in such use. It is the sole responsibility of the user to ensure familiarity with the safe and proper use of any h
9、azardous materials and to take necessary precautionary measures to ensure the health and safety of all personnel involved. 2. REFERENCES 2.1 Applicable Documents The following publications form a part of this document to the extent specified herein. The latest issue of SAE publications shall apply.
10、The applicable issue of other publications shall be the issue in effect on the date of the purchase order. In the event of conflict between the text of this document and references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws
11、 and regulations unless a specific exemption has been obtained. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7472A Page 2 of 182.1.1 SAE Publications Available from SAE International, 400 Co
12、mmonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.AMS2248 Chemical Check Analysis Limits, Corrosion and Heat Resistant Steels and Alloys, Maraging and Other Highly-Alloyed Steels, and Iron Alloys AMS2750 Pyrometry AMS563
13、7 Steel, Corrosion Resistant, Bars and Wire 18Cr - 9.0Ni (SAE 30302) Solution Heat Treated and Cold Drawn 125 ksi (862 MPa) Tensile Strength AS1132 Bolts, Screws and Nuts - External Wrenching UNJ Thread, Inch - Design Standard AS3062 Bolts, Screws and Studs - Screw Thread Requirements AS3063 Bolts,
14、Screws and Studs, Geometric Control Requirements AS8879 Screw Threads UNJ Profile, Inch Controlled Radius Root with Increased Minor Diameter 2.1.2 U. S. Government Publications Available from the Document Automation and Production Service (DAPS), Building 4/D, 700 Robbins Avenue, Philadelphia, PA 19
15、111-5094, Tel: 215-697-6257, http:/assist.daps.dla.mil/quicksearch/.MIL-STD-2073-1 DOD Materiel, Procedures for Development and Application of Packaging Requirements 2.1.3 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel
16、: 610-832-9585, www.astm.org.ASTM E353 Chemical Analysis of Stainless, Heat-Resisting, Maraging, and Other Similar Chromium-Nickel-Iron AlloysASTM E1417 Liquid Penetrant Examination 2.1.4 ASME Publication Available from American Society of Mechancial Engineers, 22 Law Drive, P.O. Box 2900, Fairfield
17、, NJ 07007-2900, Tel: 973-882-1170, www.asme.org.ASME B46.1 Surface Texture (Surface Roughness, Waviness, and Lay) 2.1.5 AIA Publications Available from Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700, Arlington, VA 22209-3928,Tel: 973-358-1000, www.aia-aerospace.org.NASM1312-8 F
18、astener Test Methods, Method 8, Tensile Testing Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7472A Page 3 of 182.2 Definitions BURR: A rough edge or ridge left on the metal due to a cutting,
19、 grinding, piercing or blanking operation. COLD ROLLING: Forming material below the recrystallation temperature. CRACK: Rupture in the material which may extend in any direction and which may be intercrystalline or transcrystalline in character.DEFECT: Any nonconformance of the unit of product with
20、specified requirements. DEFECTIVE: A unit of product which contains one or more defects. DISCONTINUITY: An interruption in the normal physical structure or configuration of a part; such as a lap, seam, inclusion, crack, machining tear, or stringer. INCLUSION: Non-metallic particles originating from
21、the material making process. They may exist as discrete particles or strings of particles extending longitudinally. LAP: Surface imperfection caused by folding over metal fins or sharp corners and then rolling or forging them into the surface. The allowable lap depth shall not exceed the limit speci
22、fied herein. The minimum condition that shall be rated as a lap is a fold having its length equal to or greater than three times its width with a depth of 0.0005 inch when viewed at 200X magnification. MACHINING TEAR: A pattern of short, jagged individual cracks, generally at right angles to the dir
23、ection of machining, frequently the result of improperly set cutting tools, or dull cutting tools. PRODUCTION INSPECTION LOT: Shall be all finished parts of the same part number, made from a single heat of alloy, heat treated at the same time to the same specified condition, produced as one continuo
24、us run, and submitted for manufacturers inspection at the same time. SEAM: Longitudinal surface imperfection in the form of an unwelded, open fold in the material. STRINGER: A solid non-metallic impurity in the metal bar, often the result of inclusions that have been extended during the rolling proc
25、ess. TIGHT BURR: A burr closely compacted and binding in the periphery of a part without any loose ends and is within the dimensional limits of the part. 2.3 Unit Symbols F - degree Fahrenheit h - hour in - inch min - minute of time % - percent (1% = 1/100) lbf - pounds force psi - pounds force per
26、square inch sp gr - specific gravity 3. TECHNICAL REQUIREMENTS 3.1 Composition Shall conform to the following percentages by weight shown in Table 1, determined by wet chemical methods in accordance with ASTM E353, by spectrochemical methods, or by other methods acceptable to purchaser: Copyright SA
27、E International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7472A Page 4 of 18TABLE 1 - COMPOSITION 3.1.1 Check Analysis Composition variations shall meet the requirements of AMS2248. 3.2 Material Heading stock shall
28、have composition specified in 3.1. Stock for machining shall be AMS5637. 3.3 Design Finished (completely manufactured) parts shall conform to the following requirements: 3.3.1 Dimensions The dimensions of finished parts, after all processing, including plating, shall conform to the part drawing. Dim
29、ensions apply after plating but before coating with solid film lubricants. 3.3.2 Surface Texture Surface texture of finished parts, prior to plating or coating, shall conform to the requirements as specified on the part drawing, determined in accordance with ASME B46.1. 3.3.3 Threads Screw thread UN
30、J profile and dimensions shall be in accordance with AS8879, unless otherwise specified on the part drawing.3.3.3.1 Incomplete Threads Incomplete threads are permissible at the chamfered end and the juncture of the unthreaded portion of the shank or adjacent to the head as specified in AS3062. 3.3.3
31、.2 Chamfer The entering end of the thread shall be chamfered as specified on the part drawing. 3.3.4 Geometric Tolerances Part features shall be within the geometric tolerances specified on the part drawing and, where applicable, controlled in accordance with AS3063. Copyright SAE International Prov
32、ided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7472A Page 5 of 183.4 Fabrication 3.4.1 Blanks Heads shall be formed by cold forging or machining. When heads are machined, AMS5637 steel shall be used. Lightening holes on forg
33、ed or machined heads may be produced by any suitable method. Wrenching recesses may be forged or machined. Flash or chip clearance in machined recesses shall not cause recess dimensions to exceed the specified limits. 3.4.2 Oxide Removal The blanks, before cold working the fillet radius when specifi
34、ed and rolling the threads, shall have surface oxide and oxide penetration removed from the full body diameter and bearing surface of the head. The oxide removal process shall produce no intergranular attack or corrosion of the blanks. The metal removed from the bearing surface of the head and the f
35、ull body diameter of the shank shall be as little as practicable to obtain a clean, smooth surface and, in no case shall be so great as to produce more cutting of flow lines in the head-to-shank junction than shown in Figure 1B. 3.4.3 Cold Working of Fillet Radius After removal of oxide as in 3.4.2,
36、 the head-to-shank fillet radius of parts having the radius complete throughout the circumference of the part shall, when specified, be cold worked sufficiently to remove all visual evidence of grinding or tool marks. Distortion due to cold working shall conform to Figure 2, unless otherwise specifi
37、ed on the part drawing. It shall not raise metal more than 0.002 in above the contour at “A“ or depress metal more than 0.002 in below the contour at “B“ as shown in Figure 2; distorted areas shall not extend beyond “C“ as shown in Figure 2. In configurations having an undercut associated with the f
38、illet radius, the cold working will be required only for 90 degrees of fillet arc, starting at the point of tangency of the fillet radius and the bearing surface of the head. For shouldered bolts, having an unthreaded shank diameter larger than the thread major diameter and having an undercut associ
39、ated with a fillet between the threaded shank and the shoulder of the unthreaded shank, the cold working will be required only for 90 degrees of fillet arc, starting at the point of tangency of the fillet radius and the shouldered surface of the unthreaded shank. For parts with compound fillet radii
40、 between head and shank, cold work only the radius that blends with the head. 3.4.4 Thread Rolling Threads shall be formed on the finished blanks by a single rolling process after removal of oxide as in 3.4.2. 3.4.5 Stress Relieving Parts, after thread rolling, shall be stress relieved by heating to
41、 700 F 10 F, holding at heat for 3 h, and cooling, exceptthat parts made of AMS5637 steel need not be so treated. Furnaces may be any type ensuring uniform temperature throughout the parts being heated and shall be equipped with, and operated by, automatic temperature controllers and data recorders
42、conforming to AMS2750. 3.4.6 Cleaning Parts, after finishing, shall be degreased and immersed in one of the following solutions for the time and temperature shown:a. One volume of nitric acid (sp gr 1.42) and 9 volumes of water for not less than 20 min at room temperature. b. One volume of nitric ac
43、id (sp gr 1.42) and 4 volumes of water for 30 to 40 min at room temperature. c. One volume of nitric acid (sp gr 1.42) and 4 volumes of water for 10 to 15 min at 140 to 160 F. 3.5 Product Marking Each part shall be identification marked as specified by the part drawing. The markings may be formed by
44、 forging or stamping, raised or depressed not more than 0.010 in maximum, with rounded root form on depressed characters. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7472A Page 6 of 183.6 P
45、lating Where required, surfaces shall be plated as specified by the part drawing. 3.7 Mechanical Properties Parts shall conform to the requirements of 3.7.1 and 3.7.2. Threaded members of gripping fixtures for proof load and tensile tests shall be of sufficient size and strength to develop the full
46、strength of the part without stripping the thread. Theloaded portion of the shank shall have two full thread turns from the thread runout exposed between the loading fixtures during the proof load and tensile tests. Finished parts shall be tested per MIL-STD-1312-8 in accordance with NASM1312-8 at r
47、oom temperature for the proof load and tensile tests. 3.7.1 Proof Load Parts shall be subjected to the load specified in Table 3 for not less than 1 min. After removing the load, the length shall have increased not more than 0.001 in. If the size or shape of the part is such that this elongation req
48、uirement would not be met but the part can be tested satisfactorily, such as parts having a shank diameter equal to or less than the thread minor (root) diameter or having an undercut, parts shall be subjected to a stress of 70 000 psi for not less than 1 min; for such parts, the diameter of the area on which stress is based shall be the actual measured minimum diameter of the part. After removing the load, parts shall have increased in length not more than 0.002 in. 3.7.2 Ultimate Tensile Strength at Room Temperature Parts shall have an ultimate tensile load not lower than that specifi
