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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/J2996_201301 AEROSPACE SURFACE VEHICLE RECOMMENDED PRACTICE J2996 JAN2013 Issued
5、2013-01 Small Diameter Fuel Line Permeation Test Procedure RATIONALE During SAE J30 Permeation testing of small diameter fuel lines, air bubbles can unknowlingly form in the fuel line and cause erroneous and inconsistent results. This new and improved weight loss test procedure, has been developed a
6、s an alternative to SAE J30, will eliminate air bubble formation resulting in improved permeation test results. TABLE OF CONTENTS 1. SCOPE 2 1.1 Purpose . 2 2. REFERENCES 2 2.1 Applicable Documents 2 2.2 Related Publications . 2 3. DEFINITIONS . 3 4. APPARATUS AND EQUIPMENT . 3 5. SAFETY EQUIPMENT A
7、ND FACILITIES . 4 5.1 Caution Notice . 4 6. TEST PROCEDURES . 4 6.1 Test Fixture Set-up and Leak Test 4 6.2 Preconditioning . 6 6.3 Weight Loss Permeation Test . 6 7. CALCULATIONS . 7 7.1 Hose internal surface area (A) 7 7.2 Calculate the daily weight loss (WLi) 7 7.3 Calculate the slope of the cumu
8、lative daily weight loss curve (m) . 8 7.4 Calculate the final Permeation Rate of the fuel hose (PRfinal) . 8 7.5 Calculate the Correlation Coefficient (r) 8 7.6 Calculate the Coefficient of Determination (R2) . 9 7.7 Additional support information required 9 8. NOTES 10 8.1 Marginal Indicia . 10 SA
9、E J2996 Issued JAN2013 Page 2 of 10 FIGURE 1 4 FIGURE 2 6 FIGURE 3 6 FIGURE 4 6 FIGURE 5 6 FIGURE 6 6 1. SCOPE This SAE Recommended Practice is intended for the determination of the losses of hydrocarbon fluids by permeation through small diameter fuel hose typically 4.75mm ID or less and typically
10、used on Small Off-Road Engines (SORE) less than 19 kW as regulated under 40 CFR Part 1054. 1.1 Purpose This document addresses specific issues associated with weight loss permeation testing of small ID fuel hose. Specifically this document is understood to be an improvement over the SAE J30 weight l
11、oss test procedure when used on small ID fuel hoses typically less than 4.75mm ID. 2. REFERENCES 2.1 Applicable Documents The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply. 2.1.1 S
12、AE 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. SAE J30 Fuel and Oil Hoses 2.2 Related Publications The following publications are provided for information purpo
13、ses only and are not a required part of this SAE Technical Report. 2.2.1 Federal Regulations Available from Electronic Code of Federal Regulations http:/ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr use an electronic balance with a readability of 0.01g or less (10 mg or less). 6.3.12 Perform the pur
14、ge procedure as described in step 6.1.6, after each weight measurement. . 6.3.13 Replace the assembly in the vertical storage position with the valve closed. 6.3.14 Continue the measuring period for the full 14 days. You may omit up to two daily measurements and its associated purging procedure (ste
15、ps 6.3.11 and 6.3.12) in any seven day period. 7. CALCULATIONS 7.1 Hose internal surface area (A) Calculate the internal exposed hose surface area (A) m2 All input dimensions are in mm. L = hose length minus the connection fitting length. ID = hose internal diameter. (PI) = constant (3.141592653) 7.
16、2 Calculate the daily weight loss (WLi) SAE J2996 Issued JAN2013 Page 8 of 10 WLi = Daily Weight Loss Wi = Test fixture weight day i Wi-1 = Test fixture weight day i-1 i = day number 7.3 Calculate the slope of the cumulative daily weight loss curve (m) Determine the slope of a linear regression of t
17、he cumulative daily weight loss ) ) ) ) CWLi = cumulative daily weight loss for the ith observation = average of the cumulative daily weight loss i = day value for the ith observation = average of the day values 7.4 Calculate the final Permeation Rate of the fuel hose (PRfinal) Divide the slope of t
18、he linear regression by the internal surface area of the fuel hose to caluclate the final permeation rate m = slope of a linear regression of the cumulative daily weight loss A = Internal surface area of the fuel hose 7.5 Calculate the Correlation Coefficient (r) Calculate the correlation coeficient
19、 for the linear regression of the cumulative daily weight loss. ( ) ( ) n = sample size which is equal to the total number of days i = day value for the ith observation CWLi = cumulative daily weight loss for the ith observation = cumulative daily weight loss for the ith observation sx = standard de
20、viation of the x measurements sy = standard deviation of the x measurements SAE J2996 Issued JAN2013 Page 9 of 10 ) ) 7.6 Calculate the Coefficient of Determination (R2) Square the correlation coeifficent to determine the coeifficent of determination R2. You may stop testing after 14 days if R2 is a
21、t or above 0.95 or if the final permeation rate calculation value is less than 50 percent of the applicable standard (ex. EPA regulatory standard or internal company test requirement). If after 14 days of testing your R2 value is below 0.95 and your final permeation rate calculation value is more th
22、an 50 percent of the applicable standard, continue testing for a total of 24 days or until R2 is at or above 0.95. If R2 is not at or above 0.95 within 24 days of testing, discontinue the test and precondition the fuel line further until it has stabilized emission levels, then repeat the testing. 7.
23、7 Additional support information required 7.7.1 Time plot showing the test temperature and optional humidity during preconditioning phase. 7.7.2 Diagram: Time plot showing the test temperature and optional humidity during the permeation weight loss test phase. 7.7.3 Certificate of Analysis for the t
24、est fuel used (includes separate analysis of the base fuel and blended in components such as Ethanol). SAE J2996 Issued JAN2013 Page 10 of 10 8. NOTES 8.1 Marginal Indicia A change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not
25、editorial changes, 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. PREPARED BY THE SAE SMALL ENGINE AND POWERED EQUIPMENT COMMITTEE
