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 2013 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/AS4296 AEROSPACE STANDARD AS4296 Issued 2013-08 Superseding ARP4296A Drawing Inte
5、rpretation and Standard Machining Practices, Couplings, Fittings and Hose Ends, Fluid Systems RATIONALE The previous version of this document, ARP4296, has been specified on several SAE Aerospace Standard (AS) drawings. It was intended to be a requirements document, but, since it was published as an
6、 ARP document, the contents were not mandatory, only recommended. Change to an SAE Aerospace Standard will make the specified contents mandatory. Some additional figures are also being added to address fluid system component drawing requirements for radii interpretation. 1. SCOPE This SAE Aerospace
7、Standard (AS) provides general information for the interpretation and clarification of engineering drawing requirements relating to the manufacture and inspection of fluid system couplings, tube fittings, and hose ends. Because it is impractical to define every minute detail of the part on the face
8、of the drawing, this standard describes interpretations of dimensioning of general machining features and otherwise undefined tolerances that fall under the heading of “good shop practice”. This standard is supplemental to ASME Y14.5M-1994 and explains, defines and interprets drawing terms or practi
9、ces that are not addressed by, ASME Y14.5M-1994. Unless otherwise specified in this standard, drawing interpretations contained in ASME Y14.5M-1994 shall apply. 2. APPLICABLE DOCUMENTS The following publications form a part of this document to the extent specified herein. The latest issue of SAE pub
10、lications shall apply. 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, sup
11、ersedes applicable laws and regulations unless a specific exemption has been obtained. 2.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AS4266 Hole Contour,
12、Fluid Passage, Tube Fitting ARP4784 Definitions and Limits, Metal Material Defects and Surface and Edge Features, Fluid Couplings, Fittings and Hose Ends SAE INTERNATIONAL AS4296 Page 2 of 8 2.2 ANSI/ASME Publications Available from ASME, 22 Law Drive, P.O. Box 2900, Fairfield, NJ 07007-2900, Tel: 8
13、00-843-2763 (U.S./Canada), 001-800-843-2763 (Mexico), 973-882-1170 (outside North America), www.asme.org. ASME Y14.5M-1994 Dimensioning and Tolerancing 3. REQUIREMENTS 3.1 General 3.1.1 Conflict in Requirements Where a conflict exists between the requirements of this document and the applicable part
14、 drawing, the part drawing shall take precedence. 3.1.2 Material Defects and Surface and Edge Flaws Unless specified on the drawing surface and edge defect definitions and limits shall be in accordance with ARP4784. 3.1.3 Sharp Edges Break edges 0.003 to 0.015 unless otherwise noted. 3.2 Tolerances
15、3.2.1 Concentricity Drawings specifying concentricity in note form modified with TIR, FIR, FIM, etc., are to be interpreted as runout per the applicable drawing interpretation standard specified. 3.2.2 Angularity 3.2.2.1 Shapes Angularity between the legs of shape fitting such as tees, elbows, and c
16、rosses shall be as shown in Figure 1. THIS IS ON THE DRAWING ALSO INCLUDES THIS /1/ Angle tolerance as specified on the part drawing FIGURE 1 - ANGULARITY OF SHAPE FITTINGS SAE INTERNATIONAL AS4296 Page 3 of 8 3.2.3 Holes 3.2.3.1 Offset The allowable fluid passage hole offset, on holes depicted as c
17、oaxial on the drawing but machined from opposite directions, shall be 0.015 maximum (see Figure 2). FIGURE 2 - OFFSET OF FLUID PASSAGE HOLES, STRAIGHT FITTINGS 3.2.4 Circularity Tolerance The circularity (roundness) tolerance of a machined diameter shall not exceed 0.0005 plus one-quarter of the dia
18、metrical tolerance and must fall within the limits of maximum material and minimum material conditions as shown in the example in Table 1. This requirement is not applicable to diameters on thin wall cylinders where the wall thickness is less than 2.5% of the ID. TABLE 1 - CIRCULARITY TOLERANCE Maxi
19、mum limit = 0.880 Minimum limit = 0.870 Diametrical tolerance = 0.010 1/4 tolerance = 0.0025 Additional tolerance = 0.0005 Total tolerance = 0.003 3.2.5 Circular Runout, Diameters on Common Axis (see Tables 2 and 3) The maximum Full Indicator Movement (FIM) between two machined diameters on a common
20、 axis shall be one-half the sum of the tolerances of the two diameters. If the resultant value from the calculation is less than 0.003, the maximum allowable FIM shall be held to 0.003. TABLE 2 - CIRCULAR RUNOUT, EXAMPLE A Diameter A is 0.490/0.510 tolerance = 0.020 Diameter B is 0.621/0.629 toleran
21、ce = 0.008 Tolerance sum = 0.028 1/2 tolerance sum = 0.014 Runout = 0.014 (FIM) SAE INTERNATIONAL AS4296 Page 4 of 8 TABLE 3 - CIRCULAR RUNOUT, EXAMPLE B Diameter A is 1.2119/1.2125 tolerance = 0.0015 Diameter B is 0.7225/0.7250 tolerance = 0.0025 Tolerance sum = 0.004 1/2 tolerance sum = 0.002 Sinc
22、e the resultant value is less than 0.003, the maximum allowable FIM shall be held to 0.003. This requirement is not applicable to diameters on thin wall cylinders where the wall thickness is less than 2.5% of the ID. 3.2.6 Machining 3.2.6.1 Threads Unless otherwise specified on the engineering drawi
23、ng, threads shall conform to requirements noted below. 3.2.6.1.1 Chamfers and Countersinks Threads shall be chamfered or countersunk as shown in Figure 3 unless otherwise specified on the engineering drawing. FIGURE 3 - THREAD CHAMFER 3.2.6.1.2 Thread Lengths Thread length as specified on an enginee
24、ring drawing shall be understood to mean that the part must comply with the thread specification requirements to the dimension noted. 3.2.6.2 Holes Holes shown on engineering drawings normally do not define the method to be used in producing the hole. While the drawing may, in some instances, imply
25、that a hole is drilled by showing a drill point or by specifying a drill depth, the manufacturer has the option to use other machining methods provided the finished hole conforms to the dimensions shown on the drawing. Unless otherwise specified, the bottom of the hole may have curved or conical con
26、tour. Elbows, qualified to 5000 psi or higher procurement specifications, shall have a spherical radius at the intersection of the two holes, as required in AS4266. An undefined conical contour in the bottom of a hole shall have a minimum included angle of 110 degrees. SAE INTERNATIONAL AS4296 Page
27、5 of 8 3.2.6.2.1 Depths Unless otherwise specified, the specified depth of a hole is to be interpreted as follows: When a fillet radius is specified between the surfaces forming the hole wall and the hole bottom, the specified depth applies to the depth of the full diameter. See Figure 4. THIS IS ON
28、 THE DRAWING MEANS THIS FIGURE 4 - HOLE DEPTH 3.2.6.3 Spotfacing Shall be interpreted as noted below. 3.2.6.3.1 Machined Faces On machining faces, the depth of the spotface shall not be greater than 0.030. 3.2.6.3.2 Forged Faces On forged faces, the depth of the spotface shall not be greater than 0.
29、060. 3.2.6.3.3 Hole and Thread Depth When a spotface callout is used in conjunction with drilled or threaded holes, the depths are to be measured from the spotface surface. SAE INTERNATIONAL AS4296 Page 6 of 8 3.2.6.4 Fillet Radii Interpretation The designation “R .XXX-.XXX” shall be interpreted to
30、mean the fillet contour shall be a faired curve that lies within the crescent shaped tolerance zone defined by the minimum and maximum limit. The contour shall be tangent at both ends and may have reversals. The radius at any point along the contour shall not be smaller than the minimum specified li
31、mit. See Figure 5. Fillet radii for spotface machining shall be 0.010 to 0.020. THIS IS ON THE DRAWING MEANS THIS FIGURE 5 - FILLET RADIUS INTERPRETATION 3.2.6.5 Edge Radius (R) Interpretation The designation “R .XXX-.XXX” shall be interpreted to mean the edge contour shall be a faired curve that li
32、es within the crescent shaped tolerance zone defined by the minimum and maximum limit. The contour shall be tangent at both ends and may have reversals. The radius at any point along the contour shall not be smaller than the minimum specified limit. See Figure 6. THIS IS ON THE DRAWING MEANS THIS FI
33、GURE 6 - EDGE RADIUS INTERPRETATION SAE INTERNATIONAL AS4296 Page 7 of 8 3.2.7 Break Edge Interpretation The note, Break Edge .XXX-.XXX, shall be interpreted as requiring a profile that: a. Will be convex or flat or a combination of both b. Will be blended into adjoining surfaces Will be wholly (inc
34、luding blends) within a tolerance zone defined by the limits specified in the note as shown in Figure 7. THIS IS ON THE DRAWING MEANS THIS *This radius is the Maximum Material Condition limit of the tolerance zone. Note that for a given value in the break edge note the radius varies in size with var
35、iations in the included angle of the edge. FIGURE 7 - BREAK EDGE INTERPRETATION 3.3 Surface Texture 3.3.1 Plated or Coated Surfaces Surface texture requirements specified on drawings shall apply prior to the application of platings or coatings. 3.3.2 Roughness Cutoff or Sampling Length Unless otherw
36、ise specified on the drawing, all surface texture measurements shall be made with a roughness cutoff of 0.030. SAE INTERNATIONAL AS4296 Page 8 of 8 4. NOTES 4.1 A change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial c
37、hanges, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. 4.2 Dimensions All dimensions are in inches. PREPARED BY SAE SAE SUBCOMMITTEE G-3B, AEROSPACE FITTINGS OF COMMITTEE G-3, AEROSPACE COUPLINGS, FITTINGS, HOSE AND TUBING ASSEMBLIES
