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 2015 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/MA2538 METRIC AEROSPACE STANDARD MA2538 Issued 1992-06 Reaffirmed 2015-04 Gasket,
5、 Metal C-Ring Seal Nickel Alloy, Corrosion and Heat Resistant, Metric Procurement Specification For FSC 5330 RATIONALE MA2538 has been reaffirmed to comply with the SAE five-year review policy. 1. SCOPE:1.1 Type:This procurement specification covers aircraft quality metallic gaskets having a “C“ sha
6、pe cross-section to form a seal ring, made from a corrosion and heat resistant age hardenable nickel base alloy of the type identified under the Unified Numbering System as N07750.1.2 Application :Primarily for aerospace propulsion system applications for sealing fluids where operating temperatures
7、excludes the use of elastomeric O-ring seals, and where the applications are relatively free from axial cyclic deflection, such as a bolted face type seal joint.1.3 Safety - Hazardous Materials :While the materials, methods, applications, and processes described or referenced in this specification m
8、ay 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 hazardous materials and to take necessary precautionary measures to ensure
9、 the health and safety of all personnel involved.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 documents shall be the issue in effect
10、 on the date of the purchase order.2.1.1 SAE Publications : Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.AMS 2645 Fluorescent Penetrant InspectionAMS 2750 PyrometryAMS 5582 Alloy Tubing, Seamless, Corrosion and Heat Resistant, 72Ni-15.5Cr-0.95(Cb + Ta)-2.5Ti-0.70Al-7.0FeAMS
11、5598 Alloy Sheet, Strip, and Plate, Corrosion and Heat Resistant, 72Ni-15.5Cr-0.95(Cb + Ta)-2.5Ti-0.70Al-7.0Fe, Consumable Electrode or Vacuum Induction Melted, Solution Heat TreatedMA2536 Gasket, Metal C-Ring, Internal Pressure, UNS N07750, Silver Plate, MetricMA2537 Groove Design, Metal C-Ring Gas
12、ket, Internal Pressure, Metric2.1.2 ANSI Publication : Available from ANSI, 11 West 42nd Street, New York, NY 10036.ANSI/ASME B46.1 Surface Texture (Surface Roughness, Waviness, and Lay)2.1.3 U.S. Government Publications : Available from Standardization Documents Order Desk, Building 4D, 700 Robbins
13、 Avenue, Philadelphia, PA 19111-5094.MIL-STD-2073-1 DoD Materiel, Procedures for Development and Application of Packaging Requirements2.2 Definitions :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 th
14、e same specified condition, produced as one continuous run, and submitted for vendors inspection at the same time.2.3 Unit Symbols :C - degree Celsiusmm - millimeterh - hourkPa - kilopascalN/mm - newton per millimetersp gr - specific gravity3. TECHNICAL REQUIREMENTS:3.1 Material :Shall be AMS 5582 s
15、eamless tubing or AMS 5598 sheet or strip.SAE INTERNATIONAL MA2538 2 OF 123.2 Design :Finished (completely manufactured) parts shall conform to the following requirements:3.2.1 Dimensions :The dimensions of internal pressure metal C-rings gaskets procured to this specification shall conform to MA253
16、6 or other applicable part drawing. Dimensions apply before plating.3.2.2 Surface Texture:Surface texture of finished parts, prior to plating, shall conform to the requirements as specified on MA2536 or other applicable part drawing, determined in accordance with ANSI/ASME B46.1.3.2.3 Geometric Tole
17、rances : Part features shall be within the geometric tolerances specified on the part drawing.3.3 Fabrication :3.3.1 Blanks:Cylindrical blanks to the required diameter and length shall be formed by cross-cutting large diameter tubing, or made from rolled flat strip stock with ends butt welded using
18、an inert gas, automated welding process.3.3.2 Forming: Blanks as in 3.3.1 shall be formed by a process using a die cavity, by rolling, or both to produce the “C“ cross-section ring.3.3.3 Heat Treatment:Formed “C“ cross-section rings as in 3.3.2 shall be solution and precipitation heat treated as fol
19、lows:3.3.3.1 Heating Equipment :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 conforming to AMS 2750. The heating medium or atmosphere shall be controlled and s
20、hall cause no surface contamination.3.3.3.2 Solution Heat Treatment : Formed “C“ cross-section rings shall be solution heat treated by heating in a suitable protective atmosphere to 980 C 15 C, holding at heat for a time commensurate with product thickness, and cooling at a rate equivalent to air co
21、ol or faster.3.3.3.3 Precipitation Heat Treatment : The solution treated rings as in 3.3.3.2 shall be precipitation heat treated by heating to 730 C 8 C in a controlled atmosphere, holding at heat for 8 hours 0.5 hours, cooling at a rate of 55 C 8 C per hour to 620 C 8 C, holding at 620 C 8 C for 8h
22、ours 0.5 hours, and cooling in air. Instead of the 55 C 8 C per hour cooling rate to 620 C 8 C, parts may be furnace cooled at any rate provided the time at 620 C 8 C is adjusted to give a total precipitation heat treatment time of 18 hours.SAE INTERNATIONAL MA2538 3 OF 123.3.4 Cleaning :Parts, afte
23、r heat treatment as in 3.3.3, shall be degreased and then 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 minutes at room temperature.b. One volume of nitric acid (sp gr 1.42) and 4 vo
24、lumes of water for 30 to 40 minutes at room temperature.c. One volume of nitric acid (sp gr 1.42) and 4 volumes of water for 10 to 15 minutes at 60 to 70 C.3.4 Identification Marking :No marking of any kind is permitted on the part. The part number and lot number shall be marked on an adhesive label
25、 and applied to the inner package (see 5.1).3.5 Plating :Where required, the part shall be plated as specified by the part drawing.3.6 Face Loading and Springback :Parts shall be compressed to the minimum groove depth specified in MA2537 for the applicable ring size. The compression load shall not e
26、xceed that specified in Table 1. The part shall be held in the compressed state for not less than 5 minutes. On release of compression load, the part shall recover (springback) by an amount, exceeding the minimum groove depth, as specified in Table 1.TABLE 1 - MA2536 C-Ring Gasket, Springback and Fa
27、ce LoadFree HeightC, mmWall ThicknessT, mmSpringbackMinimum, mmFace Load, MaximumN/mm of Circumference1.60 0.18 0.07 701.60 0.25 0.05 612.50 0.25 0.10 612.50 0.38 0.08 703.20 0.38 0.13 61SAE INTERNATIONAL MA2538 4 OF 123.7 Pressure Test:Parts shall be compressed in a fixture simulating the maximum g
28、roove depth specified in MA2537 for the applicable ring size, pressurized with air to 2100 kPa while submerging the fixture under water for 5 minutes; parts shall withstand this test with no leakage exceeding that specified in Table 2.3.8 Quality:Parts shall be uniform in quality and condition, clea
29、n, sound, smooth, and free from burrs and foreign materials and imperfections detrimental to usage of the parts.3.8.1 Sealing Area : The sealing areas of the gaskets, as defined in Figure 1, shall be free from damage and blemishes.TABLE 2 - MA2536 C-Ring GasketMaximum Permissible Leakage RateWhen Pr
30、essure Tested Per 3.4A PlatingLeakage Rate, MaximumkPa/minute/mm of A76 mm none 0.0056 76 mm Silver 0.0028 76 mm Nickel 0.0028SAE INTERNATIONAL MA2538 5 OF 12FIGURE 1 - Sealing Area of C-Ring Seals3.8.2 Fluorescent Penetrant Inspection : Parts shall be subject to fluorescent penetrant inspection in
31、accordance with AMS 2645; any required plating shall be removed for this inspection. Parts shall be free of cracks, laps, seams, inclusions, and flaws.4. QUALITY ASSURANCE PROVISIONS:4.1 Responsibility for Inspection :The vendor of parts shall supply all samples and shall be responsible for performi
32、ng all required tests. Purchaser reserves the right to sample and perform such confirmatory testing as deemed necessary to ensure that the parts conform to the requirements of this specification.4.2 Classification of Tests:Tests to determine conformance to all technical requirements of this specific
33、ation are classified as acceptance tests and shall be performed on each production inspection lot. A summary of acceptance tests is specified in Table 3.SAE INTERNATIONAL MA2538 6 OF 12TABLE 3 - Summary of Acceptance TestsTABLE 3A - Nondestructive TestsCharacteristicReq.Para.SampleSize Test MethodId
34、entification markingPackaging the size of the sample to be as specified in Table 4. The classification of dimensional characteristics shall be as specified in Table 5. All dimensional characteristics are considered defective when out of tolerance.CAUTION: Use extra care not to damage the seals in ha
35、ndling. Clean, lint-free gloves should be used during handling to prevent any residue from adhering to the gaskets. Micrometers which have a broad, flat anvil to distribute the load should be used to measure the parts rather than verniers which would be apt to dig into the plating.4.3.3 Fluorescent
36、Penetrant Inspection : A random sample shall be selected from each production inspection lot; the size of the sample shall be as specified in Table 4 and classified as in Table 5. The sample units may be selected from those that have been subjected to and passed the visual and dimensional inspection
37、, with additional units selected at random from the production inspection lot as necessary.4.3.4 Destructive Tests:A random sample shall be selected from each production inspection lot; the size of the sample shall be as specified in Table 6. The sample units may be selected from those that have bee
38、n subjected to and passed the nondestructive tests with additional units selected at random from the production inspection lot as necessary.NOTE: C-ring seals are intended to deform plastically when compressed as in 3.6 and 3.7 tests. Leakage tends to increase with reuse. Reusability is not recommen
39、ded for plated C-ring seals since they are generally used for more leakage-critical applications. Therefore, reuse of MA2536 C-ring seals are not recommended.4.3.5 Acceptance Quality : Of random samples tested, acceptance quality shall be based on zero defectives.4.4 Reports:The vendor shall furnish
40、 with each shipment a report stating that the chemical composition of the parts conforms to the applicable material specification, showing the results of tests to determine conformance to the face loading springback test, pressure test, and stating that the parts conform to the other technical requi
41、rements of this specification. This report shall include the purchase order number, lot number, MA2538, contractor or direct supplier of material, part number, nominal size, and quantity.SAE INTERNATIONAL MA2538 8 OF 12TABLE 4 - Sampling DataVisual and Dimensional CharacteristicsFor Classes Major A,
42、 Major B, Minor A, and Minor BProductionInspectionLotMajor ASampleSizeMajor BSampleSizeMinor ASampleSizeMinor BSampleSize25 and under 26 to 50 51 to 90 91 to 150 151 to 280 281 to 500 501 to 12001201 to 32003201 to 10000 10001 to 3500035001 to 150000150001 to 500000500001 & overAllAll808080801252002
43、00315500800125013132032505080125125200315500800581320323250808012520031550035813202032505080125200315SAE INTERNATIONAL MA2538 9 OF 12TABLE 5 - Classification of Visual and Dimensional CharacteristicsClass CharacteristicsMajor A101 Surface texture, sealing surface102 Face thickness variation within C
44、 limits103 Surface discontinuities revealed byfluorescent penetrant inspectionMajor B201 Face thickness, C limits202 Flatness203 Roundness204 Quality of weld area surface, if applicable205 Burrs and sharp edgesMinor A301 Average outside diameter302 Average inside diameter303 Stock thickness, TMinor
45、B401 Other dimensional characteristics not listedSAE INTERNATIONAL MA2538 10 OF 125. PREPARATION FOR DELIVERY:5.1 Packaging and Identification :5.1.1 Parts shall be individually placed in a self-closing polyethylene bag labelled as specified in 3.4.5.1.2 The outer packaging material shall consist of
46、 a rigid polystyrene lidded tray, labelled on the outside with the part number, lot number, purchase order number, and manufacturers identification.5.1.3 Packaging shall ensure delivery of parts in a clean, untarnished, and undamaged condition.5.1.4 Containers of packaged parts shall be prepared for
47、 shipment in accordance with commercial practice and in compliance with applicable regulations pertaining to the handling, packaging, and transportation of the product to ensure carrier acceptance and safe delivery.5.1.5 For direct U.S. Military procurement, packaging shall be in accordance with MIL
48、-STD-2073-1, industrial packaging, unless Level A is specified in the request for procurement.6. ACKNOWLEDGMENT:A vendor shall mention this specification number in all quotations and when acknowledging purchase orders.7. REJECTIONS:Parts not conforming to this specification, or to modifications auth
49、orized by purchaser, will be subject to rejection.TABLE 6 - Sampling DataDestructive TestsProductionInspectionLotSampleSizeUp to 500 3501 to 3200 53201 to 35000 535001 and over 8SAE INTERNATIONAL MA2538 11 OF 128. NOTES:8.1 For direct U.S. Military procurement, purchase documents should specify the following :a. Title, number, and date of this specificationb. Part number of parts desiredc. Qu
