1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW3420 Ethylene Glycol Based Extended Life Automotive Coolant DEX-COOL Copyright 2012 General Motors Company All Rights Reserved September 2012 Originating Department: North American Engineering Standards Page 1 of 9 1 Scope 1.1 Material Description.
2、This standard details the materials and performance requirements of an ethylene glycol based Organic Acid Technology (OAT) extended life engine coolant with a minimum recommended service interval of five (5) years or 150 000 miles when used at recommended concentrations. 1.2 Symbols. Not applicable.
3、 1.3 Typical Applications. The extended life engine coolant is used to protect automotive engine cooling systems from corrosion, freezing and boiling. The extended life coolant concentrate is intended to be mixed with clean, potable water per the recommended limits specified in ASTM D3306. The conce
4、ntrations to be used are specified in the Global Engine Coolant Mixture Best Practice Heating Ventilation and Air Conditioning Powertrain Cooling (HVACPTC-229) unless deviation has been granted by the Global Subsystem Leadership Team (GSSLT). 1.4 Remarks. Not applicable. 2 References Note: Only the
5、latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ASTM D412 ASTM D1287 ASTM D3182 ISO 37 ASTM D471 ASTM D1383 ASTM D3306 ISO 48 ASTM D1119 ASTM D1384 ASTM D3634 ISO 178 ASTM D1120 ASTM D1415 ASTM D4340 ISO 179 ASTM D1121 ASTM D1881 ASTM D5185
6、 ISO 527-1 ASTM D1122 ASTM D1882 ASTM D5827 ISO 1817 ASTM D1123 ASTM D2570 ASTM D6660 ISO 3167 ASTM D1177 ASTM D2809 ASTM E202 SAE J2643 2.2 GM Standards/Specifications. 9982257 GMW3059 GMW15024 GMW16594 GMN3922 GMW3155 GMW15468 GMW3038 GMW14747 GMW16270 2.3 Additional References. Global Engine Cool
7、ant Mixture Best Practice Heating Ventilation and Air Conditioning Powertrain Cooling (HVACPTC-229). The supplier shall work with the GM responsible to comprehend this requirement. GM Powertrain Assembly, Sealing and Fastening Hardware Resource Center (HRC) TMC003 Material Safety Data Sheet guidance
8、 documents (available at ). 3 Requirements 3.1 Chemical Requirements. Coolants furnished to this test procedure are OAT based and shall contain none of the following materials: Nitrite or ethanolamine containing salts or additives. Materials furnished to this test procedure shall have the compositio
9、n limits shown in Table 1. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3420 Copyright 2012 General Motors Company All Rights Reserved
10、 September 2012 Page 2 of 9 Table 1: Chemical Performance Properties - Concentrate Properties Test Methods Requirement (Weight %) A. Ethylene Glycol ASTM E202 85 minimum B. Other Glycols ASTM E202 10 maximum C. Water Note 1ASTM D1123 5 maximum (including water by hydration) D. Ash ASTM D1119 5 maxim
11、um E. Chloride ASTM D3634, ASTM D5827 25 ppm maximum F. Silicon (from Silicate) ASTM D5185 10 ppm maximum G. Phosphorus ASTM D5185 10 ppm maximum H. Boron ASTM D5185 10 ppm maximum Note 1: Water may be used to aid in the dissolution of inhibitor salts, but the amount must be controlled so that the f
12、inished product conforms to the limits specified for freezing point. 3.2 Physical Requirements. Materials furnished to this test procedure shall meet the requirements shown in Table 2. The tests will be done on the coolant concentrate unless otherwise specified. Table 2: Physical Performance Propert
13、ies Properties Test Methods Requirement A. Relative Density (15.5 C/15.5 C) ASTM D1122 1.11 to 1.14 B. Reserve Alkalinity ASTM D1121 Report titration curve C. pH ASTM D1287 1 part concentrate plus 2 parts distilled water, by volume 7 to 9 D. Equilibrium Boiling Point ASTM D1120 35% concentrate plus
14、65% distilled water by volume 163 C minimum 104 C minimum E. Freezing Point ASTM D1177 or ASTM D6660: 50% concentrate plus 50% distilled water by volume 35% concentrate plus 65% distilled water by volume 37 C maximum -20 C maximum F. Color Color Stability Test(s) as specified by Coolant Committee. C
15、olor stable orange (or alternate color as specified by Coolant Committee). G. Staining Characteristics (change in reflectance) ASTM D1882 Use panels coated with current production, light color, automobile finish No change in surface appearance by discoloration, loss of gloss, softening or swelling a
16、llowed. H. Foaming Characteristics ASTM D1881 33 by volume coolant and Type II water Increase in volume during aeration: 88 C 50 mL maximum 23 C 3 C 125 mL maximum Foam break time after end of aeration: 88 C within 5 s 23 C 3 C within 15 s Copyright General Motors Company Provided by IHS under licen
17、se with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3420 Copyright 2012 General Motors Company All Rights Reserved September 2012 Page 3 of 9 3.3 General Corrosivity. The extended life engine coolant s
18、hall contain corrosion inhibitors so that it will provide protection against metal corrosion in normally functioning systems for at least five (5) years or 150 000 miles or an extended time period as specified by the GM Commercial Contract. The candidate engine coolant shall satisfy the corrosion li
19、mits shown in Table 3 for the glassware (ASTM D1384) and simulated service (ASTM D2570) tests. The corrosion limits are given for maximum weight loss per specimen in the test indicated. The limits shown apply to the average of triplicate determinations. Single high values exceeding twice the mean va
20、lue shall be discarded and replaced by other determinations. Report any pitting and crevice corrosion which may be indications of inadequate corrosion inhibition, whether or not the weight loss exceeds the value shown. 3.3.1 Glassware Test, ASTM D1384. The glassware test shall be run both at the AST
21、M D1384 standard of -18 C (0F) freezing point and at 50 volume %. In addition to the metals shown in Table 3, weight losses shall also be reported for high lead solder (97% Pb, 2.5% Sn, and 0.5% Ag). The high lead solder weight loss is determined by repeating the ASTM D1384 test with high lead solde
22、r replacing the standard solder or by using a seven (7) metal coupon bundle containing electrically coupled high lead solder, copper, standard solder and brass specimens. 3.3.2 Simulated Service, ASTM D2570. The ASTM D2570 simulated service test shall be run at 44 volume % coolant concentrate. In ad
23、dition to the requirements shown in Table 3, there shall be no pitting, cavitations or erosion of metal components of the water pump, beyond a fairly uniform surface roughening, on conclusion of 1064 h in the Simulated Service Corrosion Test. Reserve Alkalinity (RA) shall also be determined and repo
24、rted. The RA shall not decrease by more than 25% to the endpoint pH 4.5 after completion of the Simulated Service Test. 3.3.3 GM Brazil (GMB) and other regions considering a 35% concentration may also request that the Simulated Service Test be performed using 35 volume % concentration. 3.3.4 General
25、 Corrosion Compatibility with Other Coolants. The candidate engine coolant shall also meet the ASTM D1384 requirements when tested in 1:3, 1:1, and 3:1 volumetric mixtures with the following: Coolant approved to GMW3420 and any other coolant type as selected by the Coolant Committee. Table 3: ASTM D
26、1384/ASTM D2570 Requirements Corrosion Maximum Weight Loss, mg Test Copper and Brass Solder Steel and Cast Iron Aluminum Glassware (ASTM D1384) 10 mg 20 mg 10 mg 20 mg Simulated Service (ASTM D2570) 20 mg 40 mg 20 mg 40 mg 3.4 Corrosion Inhibition at Aluminum Heat Rejecting Surfaces, ASTM D4340. The
27、 candidate engine coolant shall provide protection against corrosion of aluminum heat rejecting surfaces. The maximum allowed ASTM D4340 corrosion rate in mg/cm2 in one week for the tests described below are shown in Table 4. The values are shown as averages of duplicate tests. The formation of a tr
28、ace of solids in the test solution is permissible, but generation of enough solids to completely cover the sample after cool down is cause for rejection. The testing shall follow the procedures of ASTM D4340 with the following additions. 3.4.1 Test Solutions. In addition to the standard ASTM D4340 t
29、est solution (25 volume % coolant concentrate, 100 ppm chloride (as NaCl) in complete test solution), duplicate tests shall be run in 50 volume % coolant concentrate in deionized water on the test coolant. Other mixtures may also be requested by GM. 3.4.1.1 Cleaning Procedures. Weight losses of both
30、 test samples and blanks not exposed to coolant shall be measured twice. The first measurement is taken after the sample has been vigorously rinsed with a flow of deionized water (remove any loose solids via gentle wiping with a plastic gloved finger), rinsed with acetone, dried in an oven and coole
31、d in a desiccator. The second measurement is taken after subsequent treatment in the standard acid cleaning solution as specified in ASTM D4340. The results for both the water cleaned and acid cleaned samples shall be reported. These results should also be corrected and reported for the weight loss/
32、gain of a similarly cleaned blank specimen. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3420 Copyright 2012 General Motors Company Al
33、l Rights Reserved September 2012 Page 4 of 9 3.4.2 Compatibility with Other GM Approved Extended Life Coolants in Hot Aluminum Corrosion. The candidate coolant shall also be tested under standard ASTM D4340 conditions (25% total coolant concentrate, 100 ppm chloride) in 1:3, 1:1, and 3:1 volumetric
34、mixtures with a GMW3420 approved coolant and any other coolant selected by the GM Coolant Committee. Table 4: ASTM D4340 Requirements Candidate - Coolant Mix Reference Section Test Conditions Maximum Corrosion Rate, mg/cm2 Water Cleaned Acid Cleaned Candidate Coolant 3.4 25% Concentrate, 100 ppm Chl
35、oride 0.3 1.0 Candidate Coolant 3.4 50% Concentrate, Deionized Water 1.0 2.0 Candidate Coolant, Approved Coolant 1:3 3.4.1 25% Concentrate, 100 ppm Chloride 0.5 1.0 Candidate Coolant, Approved Coolant 1:1 3.4.1 25% Concentrate, 100 ppm Chloride 0.5 1.0 Candidate Coolant, Approved Coolant 3:1 3.4.1 2
36、5% Concentrate, 100 ppm Chloride 0.5 1.0 3.5 Cavitation Erosion Testing, ASTM D2809. The candidate coolant concentrate shall be tested under conditions outlined in ASTM D2809, Cavitation Erosion Test. A rating below eight (8) is considered basis for rejection. 3.6 Non Metallic Testing. Candidate eng
37、ine coolant as normally used in cooling systems shall have no deleterious effects on hoses, gaskets, seals, o-rings, and coatings and other cooling system components and materials. In addition to the tests defined below, other testing of materials for compatibility may be required as defined by the
38、GM Coolant Committee. Tests must be conducted with both the candidate engine coolant and an approved GMW3420 coolant except for the hose testing which is done only with the candidate coolant. The candidate coolant is required to show results that meet or improve upon the results for the approved GMW
39、3420 coolant previously released under this procedure. 3.6.1 Seal/Gasket/Polymer Test Materials. The materials to be tested are as follows: 30% Glass Filled Nylon: Any MATSPC approved source for GMW16270 and GMW3038. Elastomer: Standard Reference Elastomer, SAE J2643, Peroxide Cure Hydrogenated Nitr
40、ile Butadiene Rubber (HNBR) and GMW14747, Type C approved compound. Room Temperature Vulcanization (RTV) Silicone Sealant: Three Bond 1217F-GM per 9982257. Polypropylene: Braksem F006EC2 per GMW16594. 3.6.2 Test Method for Nylon and Elastomer. Test specimens of a single material shall be immersed in
41、 a 50 volume/50 volume or other designated mixture of coolant and potable water for 1 000 h at 125 C and 103 kPa pressures. The tests shown in Table 5 shall be performed on five (5) specimens each after 168 h and 1000 h of fluid immersion. Results for the unaged specimens (dry-as-molded for nylon) s
42、hall also be determined at the same time as the aged specimens. 3.6.3 Pressure Vessel for Fluid Immersion for Nylon and Elastomer Test. The vessel must be capable of maintaining the required temperature 2 C and pressure 20 kPa for the duration of the test (no coolant/water additions allowed), and be
43、 large enough to ensure complete immersion of the test specimens. Each test specimen must be separated from any adjacent specimen and the walls of the vessel by approximately 6 mm. Temperature, pressure, and coolant concentration shall also be reported at 168 h and 1000 h. Copyright General Motors C
44、ompany Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3420 Copyright 2012 General Motors Company All Rights Reserved September 2012 Page 5 of 9 3.6.4. Additional Test fo
45、r Nylon. The candidate engine coolant shall be tested per GMW15468, Hydrolytic Resistance of Polyamide (Nylon 6,6, Hydrolysis) and show results that meet or improve upon the results for the approved GMW3420 coolant previously released under this procedure. Test shall be performed in the 50 volume/50
46、 volume (50v/50v) mixture and any other designated mixture of coolant and potable water. 3.6.5 Compressive Stress Relaxation of Elastomer. The finished compound shall be tested to GMN3922 HNBR AM or AC2ECD0/EPDM AM or AC2ECD0. The percent (%) retained force must be reported. 3.6.6 Test Method for Si
47、licone RTV Sealant. The sealant must be tested for compatibility with the candidate coolant according to the procedures of the GM specification 9982257 for cured sealant. Both the original properties, and properties after immersion in the 50 volume/50 volume mixture or other designated mixture of co
48、olant and potable water for 240 h at 125 C, are to be determined, see Table 5. All results must be reported. Table 5: Plastic and Elastomer Test Matrix. Property/Unit Standard Specimen Conditions Nylon Tensile Strength at Yield ISO 527-1 ISO 3167 Type A Test speed 5 mm/minute Tensile Strength at Bre
49、ak ISO 527-1 ISO 3167 Type A Test speed 5 mm/minute Flexural Modulus ISO 178 80 10 4 Test speed 2 mm/minute Flexural Strength at Break ISO 178 80 10 4 Test speed 2 mm/minute Charpy Impact Strength ISO 179 80 10 4 23 C, edge impact Elastomer Tensile Strength at Break, Mpa ASTM D412/ISO 37 Die C/Type 2 Method A Tensile Stress at 100% Elongation ASTM D412/ISO 37 Die C/Type 2
