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/J2659_201207SURFACE VEHICLE STANDARD J2659 JUL2012 Issued 2003-12 Revised 2012-07
5、 Superseding J2659 DEC200 Test Method to Measure Fluid Permeation of Polymeric Materials by Speciation RATIONALE This 2012 version of SAE Vehicle standard SAE J2659 includes some editorial updates of the document released in December 2003. The appendix was updated to include an additional illustrati
6、on for measuring permeation of tubes. Although this SAE J2659 is not widely applied to fuel system materials, the speciation approach described is helpful for a more complete understanding of material permeation, especially with respect to ethanol fuels. TABLE OF CONTENTS 1. SCOPE 2 2. REFERENCES 3
7、2.1 Applicable Publications . 3 2.1.1 SAE Publications . 3 2.1.2 ASTM Publications 3 2.1.3 Federal Regulations 3 2.1.4 General Scientific Literature Publication . 4 2.2 Related Publication . 4 2.2.1 SAE Publication 4 3. DEFINITIONS . 4 4. BACKGROUND INFORMATION 7 5. APPARATUS AND EQUIPMENT . 7 5.1 P
8、ermeation Cell . 8 5.1.1 Fuel Cup 8 5.1.2 Permeate Collection Cup 8 5.2 Purge Gas Source 8 5.3 Temperature Controlled Chamber 9 5.4 Gas Chromatographic Apparatus . 9 5.5 Additional Equipment Needed in an “Open Loop” Realization of the Test . 9 5.5.1 Purge Gas Lines and valves . 9 5.5.2 Purge Gas Flo
9、w Controller 9 5.5.3 Permeate Trap 10 5.5.4 Desorbing Unit 10 5.6 Additional Equipment Needed in a “Closed Loop” Realization of the Test . 10 5.6.1 Purge Gas Lines and Valves 11 5.6.2 Membrane Gas Pump . 11 5.6.3 Vapors Injection System . 11 6. SAFETY EQUIPMENT AND FACILITIES . 11 7. TEST PROCEDURE
10、. 11 3SAE J2659 Revised JUL2012 Page 2 of 20 7.1 Test Specimen Preparation 11 7.2 Test Specimen Preconditioning 11 7.3 Mounting Test Specimen 12 7.4 Starting Test 12 7.5 Permeate Sample Collection 12 7.6 Calibration of the Gas Chromatograph . 13 7.7 Shutting Down the Test Apparatus . 13 8. CALCULATI
11、ONS AND REPORT 13 8.1 Calculate the Flux of Each Constituent and the Total Flux at Each Collection Time . 13 8.2 Obtain the Steady State Flux and the Steady Sate Vapor Transmission Rate of Each Constituent 14 8.3 Reporting Results . 14 9. ADDITIONAL INFORMATION 15 9.1 Relations with Other Measuremen
12、t Techniques . 15 9.2 Accelerating the Test in Order to Cut the Time Needed to Achieve Steady State . 15 10. NOTES 16 10.1 Marginal Indicia . 16 APPENDIX A GUIDELINES FOR SPECIATION OF FUEL LOSSES FROM FINISHED FUEL SYSTEM COMPONENTS . 17 1. SCOPE This test method described in this document covers a
13、 procedure to speciate that is, to determine the amounts of each different fuel constituent that permeates across sheets, films or slabs of plastic materials. One side of the sheet is meant to be in contact with either a liquid test fuel or a saturated test fuel vapor, the other side is meant to be
14、exposed to an environment free of fuel. The test fuel can either be a mixture of a small (usually smaller than ten) number of hydrocarbon, alcohol and ether constituents or it can be a sample of a real automotive fuel, e.g., one that may contain hundreds of different constituents. Furthermore, Appen
15、dix A contains guidelines to speciate evaporative emissions from finished fuel system components such as fuel lines, fuel filler pipes, fuel sender units, connectors and valves. SAE J2659 Revised JUL2012 Page 3 of 20 2. REFERENCES 2.1 Applicable Publications The following publications form a part of
16、 this specification to the extent specified herein. Unless otherwise indicated, the latest version of SAE publications shall apply. 2.1.1 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 (o
17、utside USA), www.sae.org. SAE J30 Fuel and Oil Hoses SAE J1527 Marine Fuel Hoses SAE J1681 Gasoline, Alcohol, and Diesel Fuel Surrogates for Materials Testing SAE J1737 Test Procedure to Determine the Hydrocarbon Losses from Fuel Tubes, Hoses, Fittings, and Fuel Line Assemblies by Recirculation SAE
18、Paper 981360 Fuel Permeation Performance of Polymeric Materials Analyzed by Gas Chromatography and Sorption Technique SAE Paper 981376 Speciation of Evaporative Emission from Plastic Fuel Tanks SAE Paper 1999-01-0376 Fuel Permeation Analysis Method Correlation SAE Paper 1999-01-0377 Vapor and Liquid
19、 Composition Differences Resulting from Fuel Evaporation SAE Paper 1999-01-0380 A Comparison of Vapor and Liquid Fuel Permeation of Fuel Systems Polymers SAE Paper 2001-01-1999 Fuel Permeation Performance of Polymeric Materials SAE Paper 2002-01-0635 Comparison of Fuel Hose SHED Test Results and Pre
20、dicted Values Using Fundamental Material Barrier Properties 2.1.2 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org ASTM E 96 Test Method for Water Transmission of Materials ASTM D 5134 Standar
21、d Test Method for Detailed Analysis of Petroleum Naphtas through n-Nonane by Capillary Gas Chromatography 2.1.3 Federal Regulations Available from the Document Automation and Production Service (DAPS), Building 4/D, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Tel: 215-697-6257, http:/assist.dap
22、s.dla.mil/quicksearch/. U.S. Code of Federal Regulations, 40 CFR, Chapter 1, Subpart B - 86.101 to 86.157 SAE J2659 Revised JUL2012 Page 4 of 20 2.1.4 General Scientific Literature Publication J.T. Scanton and D.E. Willis, “Calculation of Flame Ionization Detector Relative Response Factors Using the
23、 Effective Carbon Number Concept”, J.of Chromatographic Science. Volume 23, August, 1985 Jrn of Chromatographic Science P. O. Box 48312, Niles IL 60648 2.2 Related Publication The following publication is provided for information purposes only and are not a required part of this SAE Technical Report
24、. 2.2.1 SAE Publication 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. SAE J2260 Nonmetallic Fuel System Tubing with One or More Layers 3. DEFINITIONS 3.1 FLUX The flux, Fi(l),
25、 of a specific fuel constituent i (across a sheet, film or slab of thickness l) is defined as the rate of flow (mass per unit time) of the specified constituent in the direction normal to the face of the sheet, through a unit area of the sheet. An accepted measure of Fi(l) is gm/m2day. The test cond
26、itions (test fuel composition, temperature, pressure, etc.) must be stated. Eventually in the course of a permeation test a steady state value, Fi(ss)(l), of the flux, Fi(l), should be reached for each constituent (see 3.3). 3.2 VAPOR TRANSMISSION RATE The vapor transmission rate, VTRi, of a specifi
27、c fuel constituent (across a sheet, film or slab) is defined as the steady state rate of flow (mass per unit time) of the specified constituent in the direction normal to the face of sheet, through a unit area and for a unit sheet thickness under the conditions of the test. An accepted measure of VT
28、Ri, is gm mm/m2day. The test conditions must be stated. The steady state flux, Fi(ss)(l), and the vapor transmission rate, VTRi, are related by VTRi= l* Fi(ss)(l), where l is the film thickness. 3.3 MEASURING STEADY STATE CONDITIONS When permeation across a plastic film or sheet is measured both the
29、 amount of permeate and its composition depend on the time t that has elapsed since the film or sheet was first exposed to the fuel: in other words, each flux Fi(l), is a different function of t. Eventually, a steady state rate of permeation should be attained for each fuel constituent. In other wor
30、ds, for sufficiently long t, each flux Fi(l) should attain a constant (steady state) value, Fi(ss)(l). Of course, this can only be possible if the composition of the test fuel does not change significantly in the course of the experiment. The time required to arrive at steady state is inversely prop
31、ortional to the square of the film (or sheet) thickness and it varies greatly depending on: a. The material tested b. The composition of the test fuel c. The temperature of the experiment For the purposes of the present test it is crucial that the steady state permeation rates (as opposed to the tra
32、nsient permeation rates detected prior to the attainment of steady state) be reported. SAE J2659 Revised JUL2012 Page 5 of 20 3.3.1 Operational Criteria for Steady State An operational definition of steady state permeation may be as follows: 3.3.1.1 In the case of a test fuel constituent i, for whic
33、h the flux Fi(l) has been determined to be non zero (e.g., above the experimental quantitation limit), Fi(l) will be considered to have attained steady state at time t, provided that (within the precision of the experiment) it has remained constant for an interval of time t greater than or equal to
34、t/4. 3.3.1.2 In the case of a test fuel constituent i, for which the flux Fi(l) has remained below the experimental quantitation limit throughout the entire time t over which testing has been conducted, it is not possible to determine the steady state permeation value from the test alone. In this ca
35、se a null result should be reported together with the time t over which it has been observed. Repeating the experiment with a thinner film of the same material may yield a non null result. In using the previous operational definition of steady state it is important to keep in mind that, in general,
36、when a plastic material is exposed to a permeant (such as a test fuel), permeant is taken up by that material and the material may undergo significant changes as a result. These changes may include deformations due to swelling, changes in the material elastic properties, plasticization, changes in c
37、rystallinity and depletion of additives. All these changes affect how steady state is reached: an understanding of the changes that are likely to occur for the material and the test fuel at hand is important in assessing the test results. 3.4 TEST CONDITIONS In order for the permeation rates measure
38、d according to the present procedure to be reproduciblea necessary prerequisite for reliability and ultimate usefulnessthe following conditions under which the test procedure takes place must be carefully controlled. 3.4.1 Temperature Permeation rates are known to be greatly affected by temperature,
39、 therefore test results should state both the test temperature and its standard deviation. Permeation rates usually increase with temperature and a rule of thumb of a 10% increase in permeation per degree centigrade is often quoted. However, the rate of change of permeation with temperature depends
40、on both the material and the test fuel. For example, if the temperature of the experiment is close to the glass transition temperature of the material being tested, a much larger rate of permeation increase with temperature is to be expected. 3.4.2 Test Fuel Composition The value of the flux Fi(l) o
41、f a given fuel constituent is a function of the composition of the test fuel. Therefore it is crucial to insure that the composition of the fuel does not change significantly in the course of the experiment. This can be achieved either by using a quantity of fuel much larger than the amount likely t
42、o be lost by permeation and evaporation in the course of the test or by periodically replenishing the test fuel. SAE procedure J1681 defines a number of “standard test fluids”. 3.4.3 Pressure External pressure itself has a negligible effect on permeation, since it has a negligible effect on the chem
43、ical potential of the permeants. However, pressure differentials between the two sides of the test sheet may cause it to stretch and/or warp and thus influence the results of a permeation test. Furthermore, the saturated vapor pressure of the permeant strongly depends on temperature: this vapor pres
44、sure contributes to the total pressure at which the test fuel is held and may also cause deformations (stretching or warping) of the test sheet if the temperature is changed. In order to reduce deformations as much as possible, it is necessary to insure that the total pressure on the two sides of th
45、e film is maintained at comparable levels. For example, this can be achieved by venting the test fuel to the outside or by minimizing changes in temperature after the film has been mounted. Clearly, for a given material, the thinner the test film the greater the chances for potentially damaging elas
46、tic deformations. Conversely a sufficiently thick test sample will be able to withstand a higher pressure differential between the two sides. SAE J2659 Revised JUL2012 Page 6 of 20 3.4.4 Materials It is important to keep in mind that both the processing conditions (e.g., cast versus blow molded film
47、) and the additive package may have significant effects on permeation. Thus, it should not be surprising that films of the same polymer obtained from different manufacturers exhibit somewhat different permeation characteristics when exposed to the same test fuel. 3.4.5 Liquid versus Vapor Exposure S
48、tandard thermodynamic considerations imply that the permeation rates for films in direct contact with liquid permeant or with its saturated vapor should be the same. While there have been a large number of experimental observations confirming this rule (see SAE papers 981360 and 2001-01-1999), one o
49、bservation has also been reported where weight loss appears to depend on whether the plastic specimen is exposed to liquid or vapor (see: SAE Paper 1999-01-0380). In this case, it is possible that, the liquid in contact with the plastic material is more effective than its vapor in depleting certain additives from that material, since the presence of the liquid favors convective transport away from the surface of additives leached out of t
