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 ther
2、efrom, 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 2017 SAE International All rights reserved. No part of this
3、publication 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: +1 724-776-49
4、70 (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:/standards.sae.org/AS5316 AEROSPACE STANDARD AS5316 Issued 2017-11 Storage of Elastomer Seals and Seal Assemblies
5、 Which Include an Elastomer Element Prior to Hardware Assembly RATIONALE There has been an aerospace industry need to convert ARP5316 to an Aerospace Standard because the current document has been used as a standard even though it is a Recommended Practice. This document satisifes this need. FOREWOR
6、D Listed below is the background information which led to the creation of this Aerospace Standard. 1. Introduction of MIL-STD-1523 Age control was imposed on elastomers used in critical sealing devices of aircraft hydraulic, lubricating, and fuel systems after World War II. Several different require
7、ments and specifications were implemented in the years following the war until 1958 when ANA Bulletin 438 was released. This bulletins purpose was to collect all previous requirements for age control in one document and to make it easier for various agencies and contractors to effectively implement
8、age control. However, confusion in interpretations resulted in abuses, cost increases and inconsistently imposed exceptions. Many other programs were then undertaken to study age control. The results of many of these were summarized in the Air Force report, AFML-TR-67-235. The conclusion of the stud
9、ies summarized in this report and others that were in progress was that the overall properties of elastomeric materials were much improved over the materials initially evaluated and age control should be made less restrictive. As a result of this information, MIL-STD-1523 was released in 1973 and su
10、perseded ANA Bulletin 438. One of the basic requirements of the new document was to provide a cure date limitation of 12 quarters from cure date to acceptance of the seals by the original procuring activity, whether a government agency, a first or second contractor or an organization which assembles
11、 seal and hardware kits. In all cases, the use of cure date was intended to provide for good FIFO (First In - First Out) warehousing procedures. On February 1, 1984, MIL-STD-1523A was issued to supersede MIL-STD-1523. This revision was targeted at eliminating the confusion in interpretation of the p
12、revious document. It also extended cure date requirements from 12 quarters to 40 quarters. MIL-STD-1523A controlled the age of elastomers only at time of acceptance by the government. This meant that the cure date of each elastomer had to be known at the time a system was accepted by the government.
13、 Even with the clarifications of MIL-STD-1523A, confusion still existed and the discussion regarding the need for age control continued. SAE INTERNATIONAL AS5316 Page 2 of 16 2. Introduction of EPRI NP-6608 In June, 1989, Bruce Boyum and Jerral Rhoads presented an IEEE Paper: “Elastomer Shelf Life:
14、Aged Junk or Jewels“ - IEEE Transactions on Energy Conversion, Vol. 4, No. 2, pp. 191-203, June, 1989. After a detailed review of the information from previous studies and the age control documents including MIL-HDBK-695C, they concluded that age control limits were very conservative and shelf life
15、could be extended as long as proper storage conditions were maintained. This was followed up in May, 1994 by EPRI NP-6608, “Shelf Life of Elastomeric Components“. The conclusion of this detailed study was that with proper storage, shelf life for elastomer seals could be extended to 32 years. 3. Intr
16、oduction of AS1933A Based upon the data from the numerous studies concerning age control and shelf life, MIL-STD-1523A was canceled on January 30, 1995 - without replacement but reference was made to AS1933A. This action, in essence, released aerospace elastomers from age control. In the time since
17、the cancellation of MIL-STD-1523A confusion has reigned. Contractors are not aware of the history of age control and still insist on it. Quality organizations are not only still insisting on age control but are now using AS1933A for seals or referring to MIL-HDBK-695C. Some of the insistence for age
18、 control is due to the requirement that the latest revision of specifications shal be used and if age control or cure date requirements are removed, there is no traceability to specification revisions. In addition, organizations are concerned about FIFO requirements being maintained. 4. Introduction
19、 of ARP5316 To address the needs of contractors and to alleviate the confusion created by the cancellation of MIL-STD-1523A, ARP5316 was issued. This recommended practice addressed elastomeric seal components and offered a control document for those organizations which required one. It included reco
20、mmended shelf life limits that were consistent with the data from the cumulative studies on age control. It addressed the need for traceability and proper storage of elastomeric components of seals. It also provided a document that addressed seals not hoses, rubber boots, etc. It provided a referenc
21、e source for Quality Organizations to work with. Since it was so widely used and referenced, it is now an Aerospace Standard. The specified storage times are based upon industry input regarding practical storage limits based upon FIFO requirements. Most users of the elastomers addressed in AS5316 wi
22、ll find that the times listed in the document are beyond the time periods utilized in FIFO programs. More importantly, proper storage and traceability are specified since these are the key elements in promoting long shelf life and ensuring that the elastomeric seal components meet the latest revisio
23、n of a specification. 5. Introduction of MIL-HDBK-695 This document directs the reader to ARP5316 for questions concerning elastomer seal shelf life. 6. Introduction of DoD Manual 4140.27, Volumes 1 and 2 AS5316 is the key elastomer seal shelf life reference for complying with the shelf life extensi
24、on policy requirements of the DoD Shelf-Life Management Program Manual, Volumes 1 and 2. Paragraph 4.3 of Volume 1 specifies remaining shelf-life requirements for shelf-life items or materiel which includes elastomer seals. SAE INTERNATIONAL AS5316 Page 3 of 16 TABLE OF CONTENTS 1. SCOPE . 4 1.1 Dis
25、claimer 4 2. REFERENCES . 4 2.1 Applicable Documents . 4 2.1.1 SAE Publications 4 2.1.2 ASTM Publications . 4 2.1.3 Electric Power Research Institute Publications . 4 2.1.4 U.S. Government Publications . 5 2.2 Definitions 5 3. PACKAGING 5 3.1 General. 5 3.2 Packaging Materials . 6 3.3 Labeling 6 4.
26、STORAGE 6 4.1 Temperature . 6 4.2 Humidity . 7 4.3 Light 7 4.4 Radiation 7 4.5 Ozone . 7 4.6 Deformation 7 4.7 Contact with Liquid and Semi-Solid Materials 7 4.8 Contact with Metals 7 4.9 Contact with Dusting Powder . 7 4.10 Contact between Different Elastomers 8 4.11 Elastomeric Seals with Metal Pa
27、rts Bonded to Them 8 4.12 Stock Rotation 8 5. RECORDING OF DATA DURING STORAGE. 8 6. DISCARDING OF SEALS 8 7. STORAGE PERIOD . 8 8. NOTES . 13 8.1 Revision Indicator . 13 Appendix A . 14 Table 1 Aerospace material specifications . 9 Table 2 Military and Federal specifications . 12 Table 3 Shelf life
28、 summarized by polymer type 13 SAE INTERNATIONAL AS5316 Page 4 of 16 1. SCOPE This SAE Aerospace Standard (AS) specifies the general requirements for data recording procedures, packaging, and storing of elastomeric seals and seal assemblies which include an elastomeric element prior to the seal bein
29、g assembled into hardware components. NOTE: The requirement for packaging is an integral part of the controlled storage procedure and provides a means of positive product identity from the time of manufacture to the time of assembly into a component. 1.1 Disclaimer As AS5316 deals solely with the li
30、fe of elastomeric parts when they are being stored, this document shall not be used to justify the service life of any elastomeric component after it has been installed in any assembly, sub-assembly or any other hardware 2. REFERENCES 2.1 Applicable Documents The following publications form a part o
31、f this document 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 the purchase order. In the event of conflict between the text of this document and references cited herein, the tex
32、t of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 2.1.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA
33、and Canada) or +1 724-776-4970 (outside USA), www.sae.org. AMS2817 Packaging and Identification, Preformed Packings AS1933 Age Controls for Hose Containing Age-Sensitive Elastomeric Material 2.1.2 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshoh
34、ocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM D1418 Standard Practice for Rubber and Rubber Latices - Nomenclature 2.1.3 Electric Power Research Institute Publications Available from EPRI, 3420 Hillview Avenue, Palo Alto, CA 94304, . NP-6608 Shelf Life of Elastomeric Components SAE INT
35、ERNATIONAL AS5316 Page 5 of 16 2.1.4 U.S. Government Publications Copies of these documents are available online at http:/quicksearch.dla.mil. AFML-TR-67-235Literature Survey on the Effects of Long-Term Shelf Aging of Elastomer Materials ANA Bulletin 438Age Control of Age-Sensitive Elastomeric Items
36、 DoD Manual 4140.27: Vol. 1 DoD Shelf-Life Management Program: Program Administration Vol. 2 DoD Shelf-Life Management Program: Materiel Quality Control Storage Standards MIL-HDBK-695 Rubber Products: Recommended Shelf Life MIL-STD-1523 Age Control of Age-Sensitive Elastomeric Materials (Cancelled)
37、2.2 Definitions ELASTOMER: An elastomer is a material that possesses elastic properties and has undergone vulcanization and/or conversion into a finished product. SEAL: A seal is an elastomeric finished product or an assembly with an elastomeric element which prevents the excursion of media on one s
38、ide of the product from migrating to the other side. SERVICE LIFE: The service life of an elastomeric part is defined as the time period after installation that the seal will be required to perform the intended function. STORAGE LIFE: The storage life is the maximum period of time, starting from the
39、 time of manufacture, that an elastomeric seal element, appropriately packaged, may be stored under specific conditions, after which time it is regarded as unserviceable for the purposes for which it was originally manufactured. The time of manufacture is the time of cure for thermoset elastomers or
40、 the time of conversion into a finished product for thermoplastic elastomers. HARDWARE COMPONENT: A hardware component is a unit in which the elastomeric seal element is placed. 3. PACKAGING 3.1 General Unless otherwise specified by the customer at the time of order, the elastomeric seal or seal ass
41、embly shall be packaged: a. in individually sealed envelopes by the manufacturer, or b. in individually sealed packets in multiple envelopes by the manufacturer provided that individually packaged elastomeric seals or assemblies can be removed without affecting the seal integrity of the other packet
42、s. If the parts are repackaged by a distributor, the manufacturer will ship the properly identified parts to the distributor then the responsibility for the parts shifts to the distributor since the manufacturer cannot ensure that the parts will be properly packaged with minimum exposure to environm
43、ental conditions. The packaging shall be carried out in an atmosphere in which the relative humidity is not greater than 65%. Contamination by oil, grease, etc., shall be avoided. Seal assemblies (all components) shall be packaged in the same sealed envelope so that all elements of the assembly are
44、present when the package is opened. SAE INTERNATIONAL AS5316 Page 6 of 16 3.2 Packaging Materials All packaging materials shall be free of copper naphthenates or creosote preservatives which can degrade rubber. Suitable materials include Kraft bags and opaque polyethylene bags more than 0.003 inches
45、 (0.076) mm thick. Opaque packaging is required. Metal foil bags can be used provided they are salt free. NOTE: Phosphate ester hydraulic fluids and polyol ester based gas turbine lubricants soften and compromise polyethylene bags so care shall be taken to avoid exposure of polyethylene storage bags
46、 to fluids. 3.3 Labeling Unless otherwise directed by the customers drawing or procurement document, each package or container shall be labeled with the following information which shall be visible from the outside of the package without breaking the seal: a. Manufacturers part number; b. Specificat
47、ion number and Revision level; c. Customers part number and/or contract number (if requested); d. Quantity in package; e. Manufacturers name and/or identity number (such as CAGE Code); f. Quarter and Year of cure or manufacturer of the rubber component (e.g., July to September 1997 = 3Q97); g. Manuf
48、acturers batch number; h. Rubber class designation per ASTM D1418; i. Packagers name (if different from manufacturer) and packaged date. The expiration date shall only be added to the label if the seal is to be purchased directly by the military procurement agencies. AMS2817 allows individually pack
49、aged parts to be supplied to a distributor who can then allocate them to orders, if parts are purchased from the manufacturer under one contract number and then sold, without being repackaged, by the supplier to the consumer under a different contract number, the original contract number shall be crossed out and the new contract number applied in the heat seal area of the envelope. Thus cradle to grave traceability an
