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 entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.Copyright 2005 SAE InternationalAll rights reserved. No part of this publication may be
3、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: 724-776-4970 (outside USA)Fax: 724-
4、776-0790Email: custsvcsae.orgSAE WEB ADDRESS: http:/www.sae.orgSURFACEVEHICLERECOMMENDEDPRACTICEJ1684REAF.SEP2005Issued 1994-01Reaffirmed 2005-09Superseding J1684 JUN2000Test Method for Evaluating the Electrochemical Resistanceof Coolant System Hoses and Materials1. ScopeThis test method provides a
5、standardized procedure for evaluating the electrochemical resistance ofautomotive coolant hose and materials. Electrochemical degradation has been determined to be a majorcause of EPDM coolant system hose failures. The test method consists of a procedure which induces voltageto a test specimen while
6、 it is exposed to a water/coolant solution. Method #1, referred to as a “Brabolyzer”test, is a whole hose test. Method #2, referred to as a “U” tube test, uses cured plate samples or platesprepared from tube material removed from hose (Method No. 2 is intended as a screening test only). Any testpara
7、meters other than those specified in this SAE Recommended Practice, are to be agreed to by the testerand the requester.1.1 RationaleThis document has been reaffirmed to comply with the SAE 5-Year Review policy.2. References2.1 Related PublicationsThe following publications are provided for informati
8、on purposes only and are not arequired part of this document.R. C. Keller, SAE Technical Paper 900576, February 28, 1990Harold Schneider, Hal Tucker, Dr. Eddie T. Seo, Rubber Division, ACS Technical Paper 73, May 22, 19923. Method #1 “Brabolyzer,” Whole Hose TestMaterials and Equipment Required3.1 1
9、2 V DC power supply.3.2 Multivolt ohmmeter.3.3 Commercial automotive coolant, ethylene glycol based containing an inorganic anticorrosion protectionsystem, shall be used These coolants are typically green in appearance.3.4 End plugs chemically resistant, electrically nonconductive thermoplastic as p
10、olyamide, PTFE, orpolypropylene suitable for isolating voltage applied to end of hose from the liquid test media inside the hose.Electrical contact surface for applied voltage should be the inside circumference of test hose. See Figures 1Aand 1B for end plug assembly components. The end plugs shown
11、are for 31.8 mm ID hose, which is preferred,but other sizes can also be made.SAE J1684 Reaffirmed SEP2005-2-3.5 Glass insulator to isolate electrically the hose samples attached to the negative and positive terminals. SeeFigure 2.3.6 Suitable hose clamps for size of hose used.3.7 Air-circulating ove
12、n configured with wooden or other nonconducting surface for complete electrical isolation oftest assembly.3.8 Suitable electrical leads and clips for connecting power source to end plug.3.9 Microscope (10X to 20X) for examination of specimens after test. A stereo microscope is best, using a fiber-op
13、tic light source that can be adjusted for angle.3.10 Two 100 mm straight samples for each cell. Curved hose may be used if straight hose is not available.4. Set-Up Procedure4.1 Attach one end-plug flush to one end of test hose with appropriate clamp.4.2 Attach glass insert between the two test hoses
14、 with appropriate clamps.4.3 Fill hose assembly 80% 5% by volume with a solution of 50:50 distilled water/coolant.4.4 Attach second end plug to test specimen with appropriate clamp.4.5 Mark specimen with pertinent identification and positive or negative polarity. Marking should be on the top sideof
15、the hose as it lays in the oven for use as a reference point.4.6 Make three of the previous completed assemblies per test. See Figure 3.5. Test Procedure5.1 Place test hose assemblies in air-circulating oven which has been configured to electrically isolate theassemblies. Attach leads to assemblies
16、at the end plugs, ensuring that polarity is consistent with markings.Use volt/ohmmeter to ensure continuity through all components measured with voltage off. Voltagemeasurements may vary through each hose assembly.5.2 Apply 12 V, and measure voltage from plug to plug and record. Also measure voltage
17、 at source (before hosecircuit) and record. If a significant difference exists, check all leads and connections. Voltage may or may notbe the same. However, it is critical to ensure that all connections are properly made.5.3 Heat oven to 100 C 2 C. Visually check liquid level through glass insulator
18、 each day, replenishing liquid, if itdrops below 50%.5.4 After 168 h 0.5 h, detach leads and remove assemblies from oven and allow to cool to room temperature.5.5 Remove end plugs and drain fluid from hose. Rinse hose interior thoroughly.5.6 Cut the negative end of the hose approximately 45 mm from
19、hose end. A smooth, straight cut through thehose with a sharp blade instrument is desirable for examination purposes.5.7 Examine the cross section of the cut end under magnification (10X to 20X) with a bright, low angle light. Makenote of striations. The striations may be long and thin, short and th
20、ick, branched or unbranched, liquid filled ordry, or any combination of the previous. Do not confuse knife cut marks with striations.SAE J1684 Reaffirmed SEP2005-3-FIGURE 1APOLYPROPYLENE HOSE PLUGSAE J1684 Reaffirmed SEP2005-4-FIGURE 1BELECTRODESAE J1684 Reaffirmed SEP2005-5-FIGURE 2GLASS TUBE WITH
21、BEADS ON ENDSSAE J1684 Reaffirmed SEP2005-6-FIGURE 3BRABOLYZER TEST CONFIGURATIONSAE J1684 Reaffirmed SEP2005-7-6. Report6.1 Report any striations noted during the microscopic examination. Any striations constitute a failure. Additionaldescriptions such as length, percent of circumference affected,
22、location, branching, moisture present, as wellas pictures are helpful in determining degree and type of damage.7. Method #2 “U” TubeMaterials and Equipment Required7.1 12 V DC power supply.7.2 Multivolt ohmmeter.7.3 Commercial automotive coolant, ethylene glycol based containing an inorganic anticor
23、rosion protectionsystem, shall be used. These coolants are typically green in appearance.7.4 Test specimen, die-cut from standard laboratory press cure stock. A die-cut sample from the tube removedfrom a hose may also be used. Dimensions are 10 mm wide x 100 mm long.7.5 Glass “U” tube assembly.7.6 T
24、hermostatically controlled heating bath, using water soluble oil as a heating medium. The temperature of thebath oil shall be set at 80 C.7.7 Hook-up wire and crocodile clips.7.8 Balance capable of weighing to 0.01 g.8. Set-Up Procedure8.1 Connect the hook-up wire to the crocodile clip and insert th
25、rough the glass insulation tube as shown in Figure 4.8.2 Weigh negative test specimen, bend the strip into a loop and clamp the ends with the crocodile clip.8.3 Prepare a sufficient quantity of 50:50 coolant:distilled water for all tests.8.4 Add 100 mL of the liquid prepared in 8.3 to the “U” tube a
26、pparatus.8.5 Place a bent loop test specimen, held in place with the crocodile clip, and glass insulation tube into each arm ofthe “U” tube.8.6 Loosen the screw cap on the Teflon ball joint and slide the glass tube up or down to adjust the immersiondepth of the specimen. The test sample should be ma
27、rked 12.5 mm from each end, and the looped specimenimmersed in the test fluid to those marks. This ensures that 75% of the specimen is immersed in the fluid.Repeat the process, placing another test specimen in the other arm of the “U” tube.8.7 Place each “U” tube into the heating bath and clamp so t
28、hat the coolant solution in the apparatus is just belowthe level of the heating oil liquid in the bath.NOTEThe bath should be at the desired temperature before placing the “U” tube in it.SAE J1684 Reaffirmed SEP2005-8-FIGURE 4”U” TUBE APPARATUS TO DETERMINE ELECTROCHEMICAL RESISTANCE8.8 Connect each
29、 “U” tube to the power supply.NOTELabel the positive and negative polarity of each of the connections and label the polarity on each armof the “U” tube.8.9 Make three of the previous assemblies per test, see Figure 4.9. Test Procedure9.1 Turn on the power supply and adjust the voltage to 12 V. Turn
30、on each circuit as required. The current may bemonitored, and recorded if desired.9.2 After the test period, 168 h 0.5 h, is completed, turn off power to each circuit. Carefully loosen the Teflonball joint from the “U” tube and remove the ball joint from the crocodile clip. Note the polarity of each
31、 sample.Rinse sample in water, blot, and weigh immediately. Record the weight of the negative sample only.9.3 Calculate the percent weight increase as follows in Equation 1:(Eq. 1)100Final wt. Initial wt.Initial wt.SAE J1684 Reaffirmed SEP2005-9-10. Report10.1 Test conditions of temperature, voltage
32、, and duration.10.2 Initial weight, final weight, and percent weight increase of the negative end test specimens.10.3 Report the median value of the three negative test specimens.10.4 A weight increase of the median value of the negative end test specimen in excess of 5% indicates thecompound may not be electrochemically resistant. Method No. 2 is intended as a screening test only.PREPARED BY THE SAE NON-HYDRAULIC HOSE COMMITTEE
