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 there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2012 SAE International All rights reserved. No part of this p
3、ublication may 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: +1 724-776-497
4、0 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AS5447 AEROSPACE STANDARD AS5447 Issued 2000-12 Reaffirmed 2012-11 Acceptance Cri
5、teria for Nuts - Magnetic Particle, Fluorescent Penetrant, and Visible Penetrant Examination RATIONALE AS5447 has been reaffirmed to comply with the SAE five-year review policy. SAE AS5447 Page 2 of 8 2.1.1 ASTM Publications: Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-29
6、59. ASTM E 1417 Liquid Penetrant Examination ASTM E 1418 Visible Penetrant Examination Using the Water-Washable Process ASTM E 1444 Magnetic Particle Examination 2.2 Definitions: BURR: A rough edge or ridge left on the metal due to cutting, grinding, piercing, or blanking. CIRCULAR INDICATION: Any r
7、ateable discontinuity in the general direction around the thread axis (transverse), see Figure 1. CRACK: A crystalline fracture passing through or across grain boundaries without inclusion of foreign elements. Cracks are normally caused by overstressing the metal during forming, or during heat treat
8、ment. DISCONTINUITY: An interruption in the normal physical structure or configuration of the part; such as a crack, inclusion, machining tear, lap, seam, or stringer. FORMING TEARS: Pattern of short, jagged individual slits, generally at right angles to the direction of metal working, see Figure 2.
9、 GRINDING CHECK: Fine thermal cracks that develop from overheating of the area being ground. Such cracks are generally at right angles to the direction of grinding but may appear as a complete network. INCLUSION: Nonmetallic particles inherent in the material when it was made. These particles may be
10、 isolated or distributed in the form of longitudinal stringers. INDICATION: An indication is visual evidence of a discontinuity, as revealed by magnetic particle or liquid penetrant examination. LAMINATIONS: Found only in plate steel, and are thin flat discontinuities seen only at the edge of the pl
11、ate. LAP: A surface imperfection appearing as a seam or crack, caused by folding of the material during operations as forming, forging, rolling, or drawing. LINEAR INDICATION: Any rateable discontinuity in the general direction of the thread axis (longitudinal), see Figure 3. MACHINING TEAR: A patte
12、rn of short, jagged individual cracks, generally at right angles to the direction of machining. Frequently the result of improperly set cutting tools, or dull cutting tools. SAE AS5447 Page 3 of 8 FIGURE 1 -Typical Circular Indications SAE AS5447 Page 4 of 8 FIGURE 2 -Typical Forming Tears SAE AS544
13、7 Page 5 of 8 FIGURE 3 -Typical Linear Indications SAE AS5447 Page 6 of 8 2.2 (Continued): NICKS or PITS: Depressions or indentations in the surface of the metal. NON-RATEABLE INDICATION: Any discontinuity, regardless of location, with a depth less than or equal to 0.0005 in. PIPE: A discontinuity i
14、n the center of a rolled bar. It is caused by internal cavities in the ingot formed during solidification and which have become elongated or stretched in the rolling operations. RATEABLE INDICATION: Any discontinuity, regardless of location, with a depth greater than 0.0005 in. SEAM: Open surface im
15、perfection that is narrow and continuous, usually straight, running generally parallel to the bar axis. Seams are generally inherent in the bar from which the part is formed. STRINGER: A solid nonmetallic impurity in the parent metal, often the result of inclusions that have been extended during the
16、 rolling process. 3. TECHNICAL REQUIREMENTS: 3.1 General Indications: Where this standard is specified as the acceptance criteria for nondestructive examination of discontinuities, it shall apply in support of ASTM E 1444 for magnetic particle examination, ASTM E 1417 for fluorescent penetrant exami
17、nation, and ASTM E 1418 for visible penetrant examination. The part marking requirement for identification of magnetic particle or penetrant inspection is waived. 3.1.1 Multi-piece nuts such as gang channel or floating plate nuts shall be inspected prior to assembly. When the multi-piece nut is heat
18、 treated after assembly, the nuts shall be inspected as an assembly. 3.1.2 Indications in themselves shall not be cause for rejection. Representative samples shall be taken from those nuts having indications and examined metallurgically at 1 OX magnification to determine if the discontinuities are o
19、utside the applicable limits permitted for rateable indications. 3.2 Acceptance Criteria: 3.2.1 Unless otherwise specified, parts with rateable or non-rateable indications shall show no indications of cracks, laminations, machining tears, pipes, or grinding checks. However, forming tears, which appe
20、ar as cracks on the wrench pads, are acceptable provided the depth does not exceed the limits specified in Table 2. 3.2.2 Except as noted in 3.2.1, parts with non-rateable indications are acceptable. SAE AS5447 Page 7 of 8 TABLE 1 -Permissible Surface Discontinuities for Circular Indications, Except
21、 Forming Tears Dimensions in inches Nominal Discontinuity Nominal Discontinuity Thread Depth- Thread Depth-Diameter Maximum Diameter Maximum 0.1120 0.0040 0.6250 0.0100 0.1250 0.0040 0.7500 0.0100 0.1380 0.0050 0.8750 0.0100 0.1640 0.0050 1.0000 0.0110 0.1900 0.0050 1.1250 0.0110 0.2500 0.0050 1.250
22、0 0.0110 0.3125 0.0060 1.3750 0.0120 0.3750 0.0060 1.5000 0.0120 0.4375 0.0070 1.7500 0.0120 0.5000 0.0080 2.0000 0.0120 0.5625 0.0090 - -TABLE 2 - Permissible Surface Discontinuities for Linear Indications, and Forming Tears on the Wrench Pads Dimensions in inches Nominal Discontinuity Nominal Disc
23、ontinuity Thread Depth- Thread Depth-Diameter Maximum Diameter Maximum 0.1120 0.0020 0.6250 0.0050 0.1250 0.0020 0.7500 0.0050 0.1380 0.0025 0.8750 0.0050 0.1640 0.0025 1.0000 0.0055 0.1900 0.0025 1.1250 0.0055 0.2500 0.0025 1.2500 0.0055 0.3125 0.0030 1.3750 0.0060 0.3750 0.0030 1.5000 0.0060 0.437
24、5 0.0035 1.7500 0.0060 0.5000 0.0040 2.0000 0.0060 0.5625 0.0045 - -SAE AS5447 Page 8 of 8 3.2.3 Parts with rateable linear or circular indications exceeding the applicable limits in Table 1 or Table 2 are not acceptable. 3.2.4 Parts with a rateable indication, burr or other surface interruptions th
25、at impair the performance of the part, e.g., function or fit of thread, locking feature, or bearing surface flatness, are not acceptable. 4. QUALITY: Parts shall be uniform in quality and condition, free from loose burrs, foreign materials, and from imperfections detrimental to the usage of the part. PREPARED UNDER THE JURISDICTION OF SAE COMMITTEE E-25, GENERAL STANDARDS FOR AEROSPACE PROPULSION SYSTEMS
