PROCEEDINGS OF THE INSTITUTE OF VEHICLES 2(106)/2016 (12 pt) (12 pt) Henryk Bąkowski 1, Zbigniew Stanik 2 (12 pt) THE TEST OF THE COOLING FLUID WEAR USED IN MOTOR VEHICLES (12 pt) 1. Introduction Cooling systems are often poorly supported by the users because they are not a safety when driving a motor vehicle. Members and vehicle mechanics forget, however, that the poorly operated cooling system results in faster wear of major engine parts such as cylinder liners, piston rings, water pumps. Lack of correct operation of the cooling system can lead to increased fuel consumption and costly repairs combustion engines. The cooling systems of the engine used for the liquid, which are based on ethylene glycol or propylene glycol and water. These fluids must comply with the relevant standards Polish and international so that they can be used in internal combustion engines. Approved for use cooling fluids, like any consumable wear. It is important, therefore, to what extent and how long the liquid should be replaced and how to check their condition. (8 pt) 2. Test equipment and materials In order to determine the parameters of antifreeze fluid, uses suitable measuring devices, matched to each of these parameters and benefited from different materials for research (Fig. 1, 2). To research used the glycols contained in the cooling systems of internal combustion engines. Research antifreeze were divided into two types: - Laboratory tests. - Operational tests which were used 15 samples taken from the vehicle with a known period of use. For each of the samples in laboratory tests performed, a single measurement of the following parameters: freezing point of the fluid using the refractometer, percent concentration of ethylene glycol in a sample using a refractometer, the boiling point of the liquid in the operating conditions (in a closed vessel), the foam disappearing time in a liquid, ph levels. During the field tests for each sample, measurements of the following parameters: freezing point of the fluid using the refractometer and two types of hydrometers, percent concentration of ethylene glycol in a sample using a refractometer, the boiling point of the liquor using a hydrometer, the boiling point of the liquid in the operating conditions (in a closed vessel), the foam disappearing time in the cooling fluid, the ph of the liquid. 1 Ph.D. Henryk Bąkowski, Assist. Prof., Faculty of Transport, Silesian University of Technology 2 Prof., dr hab. inż. Zbigniew Stanik, Assoc. Prof., Faculty of Transport, Silesian University of Technology 5
a) b) c) d) e) Fig. 1. Research equipment: a) refractometer, b), aerometer, c) ph meter, d) bottle, e) pressure cooker 6
a) b) Fig. 2. Materials to tests: a) aluminum sample, b) cooper sample 3. Results The measurement results are shown on Figure 3, 4 and table 1. The results of the time the disappearance of foam in cooling fluid presented in table 1. Table 1. Results a) Fig. 3. Cooling fluid after the test 7
Time, s Graph of the foam disappearing time of the concentration of ethylene glycol in the cooling fluid are shown on figure 4. 75 50 25 0 0 20 40 60 The concentration of ethylene glycol, % Fig. 4. The time vs. ethylene glicol concentration Laboratory tests and operational demonstrate that antifreeze has a tendency to foam. This parameter is rarely described in other publications, although the impact of foam on the removal of heat from combustion engines is negative. Studies show that only liquids having a concentration close to 50% ethylene glycol from a foam disappearing time in accordance with standard (Fig. 4). Fig. 5. Glycol concentration vs. number of year This diagram depend on the correctly routine maintenance (Fig. 5-7). 8
Boiling temperature, oc Fig. 6. Reducing the pressure causes a large amount of gas 144 140 136 132 128 124 120 0 5 10 15 20 Number of year Fig. 7. Boiling temperature vs. number of year 3.2. Metallographic results Metallographic examinations have been carried out on microscope under x100 magnifcation (Fig. 8) and results obtained by means of software to quantitative metallographic analysis (Table 2). a) Alluminium sample Cooper sample 9
b) c) Alluminium sample Cooper sample Alluminium sample Cooper sample Fig. 8. Surface of samples attacked by corrosion in pressure cooker The results of the cooling fluid effect on the corrosion presented on table 2. Table 2. Results 10
Conducted operational tests have shown that only one sample of fluid taken from the vehicle (Combo), meets the requirements specified in the standards. It was therefore concluded that the 15 vehicles with the sampled fluid, 93% of these vehicles have fluid unfit for further use. 4. Conclusion Based on the study, it was found that: time has no effect on the deterioration of the performance parameters with the exception of the effect of antifreeze to the corrosion, the contribution of corrosion on the test plates varies with the period of use the fluid. This change is increasing, which shows that the older the less liquid corrosion inhibitor is contained therein. Antifreeze impact on the formation of corrosion, also depends on the percentage concentration of ethylene glycol in the fluid. 8 pt) References: [1] Płyny niskokrzepnące do układów chłodzenia silników spalinowych Oznaczanie temperatury wrzenia. Standard PN-92/C-40008/03. [2] Płyny niskokrzepnące do układów chłodzenia silników spalinowych Badanie właściwości korozyjnych w naczyniu szklanym Standard PN-93/C-40008/07. [3] Dytkowicz B., Grobelny M., Kalisz M., Rudnik D.: Wykorzystywanie inhibitorów korozji do ochrony układu chłodzenia silnika spalinowego. Instytut Transportu Samochodowego. Transport Samochodowy 3-2011. Abstract The engines stand out a lot of systems to provide correct operation of these engines, they also include the cooling system, which is designed to maintain a constant temperature and optimum operating conditions of the engine. Cooling systems are often badly supported by the users because they do not represent safety when driving a motor vehicle. Users and vehicle mechanics forget, however, that the badly operated cooling system cause faster wear of major engine parts such as cylinder liners, piston rings, water pumps. No correct handling of the cooling system can contribute to increased fuel consumption and costly repairs combustion engines. The cooling systems of the engine used for the fluids called antifreezing, which are based on ethylene glycol or propylene glycol and water. These fluids must comply with the the appropriate standards Polish and international so that they can be used in internal combustion engines. Research antifreeze were divided into laboratory studies in which samples of antifreeze have been artificially hydration and operational tests in which samples were taken antifreeze from the vehicles of known period of use and have been tested and compared with the results of laboratory tests. Keywords: antifreeze, corrosion wear. 11
BADANIA ZUŻYCIA PŁYNÓW CHŁODZĄCYCH WYKORZYSTYWANYCH W POJAZDACH SAMOCHODOWYCH Streszczenie W silnikach spalinowych wyróżnia się wiele układów zapewniających prawidłową pracę tych silników, zalicza się do nich także układ chłodzenia, który ma za zadanie utrzymać stałą temperaturę oraz optymalne warunki pracy silnika. Układy chłodzenia są często źle obsługiwane przez użytkowników ponieważ nie stanowią one o bezpieczeństwie podczas jazdy pojazdem samochodowym. Użytkownicy oraz mechanicy pojazdów zapominają jednak, że źle eksploatowany układ chłodzenia powoduje szybsze zużywanie się istotnych części silnika takich jak: tuleje cylindrów, pierścieni tłokowych, pomp wodnych. Brak poprawnej obsługi układu chłodzenia może przyczynić się do podwyższonego zużycia paliwa oraz kosztownych napraw silników spalinowych. W układach chłodzenia silnika stosuje się przeznaczone do tego ciecze zwane płynami niskokrzepnącymi, które są oparte na bazie glikolu etylenowego lub propylenowego oraz wody. Płyny te muszą spełniać wymagania odpowiednich norm polskich oraz międzynarodowych aby mogły być eksploatowane w silnikach spalinowych. Dopuszczone do eksploatacji płyny chłodzące, jak każdy materiał eksploatacyjny, zużywają się. Istotne jest zatem w jakim stopniu i po jakim czasie płyny powinny zostać wymienione i jak należy sprawdzać ich stan techniczny. Słowa kluczowe: płyn chłodzący, zużycie korozyjne (przez utlenianie). 12