The quality of motor oils for passenger vehicles is defined by international specifications (ACEA-Association des Constructeurs Europeens d'Automobiles, API-American Petroleum Institute, ...ILSAC-International Lubricant Standardization & Approval Committee) and specifications by the reputable engine/vehicle manufacturers. One among the goals of introducing ACEA specifications back in 1996 was the joining together of all requirements by European vehicle manufacturers. Sadly, this goal has never been achieved, so that we are now witnessing the appearance of a growing number of specifications by individual vehicle manufacturers. The number of passenger vehicle motor oil specifications is increasing for two reasons. There are new vehicle manufacturers with motor oil specifications appearing, while those who have already had specifications are increasing their number. The situation is furtherly worsened by the fact that the requirements of individual vehicle manufacturers are mutually inconsistent. A direct consequence of the said situation is that motor oil manufacturers are forced to keep widening their assortment of motor oils, which renders oil development and production considerably more expensive. Especially difficult is the position of small-scale oil manufacturers who find it very difficult to meet the increased costs of testing a large number of motor oils.
Kvaliteta motornih ulja za osobna vozila definirana je medunarodnim specifikacijama (ACEA - Association des Constru-cteurs Europeens d'Automobiles, API - American Petroleum Institute, ILSAC - ...International Lubricant Standardization & Approval Committee) i specifikacijama najpoznatijih proizvodaca motora/vozila. Jedan od ciljeva uvodenja ACEA specifikacija 1996. godine bio je objedinjavanje svih zahtjeva europskih proizvodaca vozila. Nazalost, u tome se nije uspjelo tako da smo svjedoci pojave sve veceg broja specifikacija pojedinih proizvodaca vozila. Broj specifikacija motornih ulja za osobna vozila povecava se zbog dva razloga. Pojavljuju se novi proizvodaci vozila sa specifikacijama motornih ulja, dok proizvodaci vozila koji su i do sada imali specifikacije povecavaju njihov broj. Situaciju pogorsava i cinjenica da su zahtjevi pojedinih proizvodaca vozila medusobno nesukladni. Direktna posljedica navedene situacije jest da su proizvodaci motornih ulja prisiljeni proizvoditi sve siri asortiman motornih ulja sto znacajno poskupljuje razvoj i proizvodnju ulja. Posebno je otezana pozicija manjih proizvodaca ulja, koji tesko mogu podnijeti povecane troskove ispitivanja velikog broja motornih ulja.
Multigradna motorna ulja uz veci broj dodataka, aditiva, uvijek sadrze i aditive za povecanje indeksa viskoznosti - poboljsavala indeksa viskoznosti. Ti aditivi su posebne vrste polimernih tvari, ...koje i u malim koncentracijama znacajno poboljsavaju njihova reoloska svojstva, posebice viskoznost i indeks viskoznosti. Medutim, tijekom eksploatacije motornog ulja dolazi do razgradnje, kidanja polimernih molekula poboljsavala indeksa viskoznosti, smanjenja njihove molekulne mase, sto dovodi do pada viskoznosti i smanjenja debljine uljnog sloja te izaziva nezeljene pojave trenja i trosenja. Smicna stabilnost poboljsavala indeksa viskoznosti, odnosno otpornost polimera na mehanicku degradaciju pod djelovanjem smicnog naprezanja odreduje se mjerenjem pada viskoznosti nakon visekratnog prolaska ulja kroz brizgaljku. Specifikacije motornih ulja definiraju minimalnu vrijednost viskoznosti ulja nakon smicanja. Uvodenjem novih ACEA i API specifikacija doslo je do promjene u zahtjevu za odredivanje smicne stabilnosti motornih ulja koju su prihvatili i proizvodaci motora i vozila. S ciljem sto bolje korelacije s rezultatima iz eksploatacije motornih ulja definirano je da se odredivanje smicne stabilnosti u normiranom uredaju produzi s dosadasnjih 30 na 90 ciklusa prolaska ulja kroz brizgaljku. U radu je prikazano ispitivanje smicne stabilnosti najznacajnijih vrsta komercijalnih poboljsavala indeksa viskoznosti Orbahn diesel injector uredajem pri produzenom testu smicne stabilnosti (90 ciklusa) s ciljem zadovoljenja novih specifikacija motornih ulja.
Multigrade engine oils among numerous additives, always contain also viscosity index improvers. These additives are special types of polymers, which in small concentration significantly improve ...engine oils rheological properties, especially viscosity and viscosity index. However, during engine oils utilization, degradation of viscosity index improvers ie. break down of polymeric molecules occures. It results in reduction of their molecular weight what leads to viscosity loss and oil film thickness decrease, which causes undesirable phenomena of friction and wear. The shear stability of the viscosity index improvers that is the polymer resistance to mechanical degradation under shear stress is determined by measuring of the viscosity loss after repeated oil passing through the injector nozzle. The engine oil specifications define the minimal oil viscosity grade after the shear. By introducing the new ACEA and API specifications, the requirements for the shear stability of engine oils have been changed and now they are accepted by engine and vehicle manufacturers. In order to achieve better correlation with engine oil application results, it is defined that the shear stability should be determined by standardized apparatus extending current testing of 30 to 90 cycles of oil passing through the nozzle. The paper presents the shear stability testing of most important types of commercial viscosity index improvers on Orbahn diesel injector apparatus at extended shear stability test (90 cycles) with aim on meeting the new engine oil specifications.
Multigrade engine oils among numerous additives, always contain also viscosity index improvers. These additives are special types of polymers, which in small concentration significantly improve ...engine oils rheological properties, especially viscosity and viscosity index. However, during engine oils utilization, degradation of viscosity index improvers ie. break down of polymeric molecules occures. It results in reduction of their molecular weight what leads to viscosity loss and oil film thickness decrease, which causes undesirable phenomena of friction and wear. The shear stability of the viscosity index improvers that is the polymer resistance to mechanical degradation under shear stress is determined by measuring of the viscosity loss after repeated oil passing through the injector nozzle. The engine oil specifications define the minimal oil viscosity grade after the shear. By introducing the new ACEA and API specifications, the requirements for the shear stability of engine oils have been changed and now they are accepted by engine and vehicle manufacturers. In order to achieve better correlation with engine oil application results, it is defined that the shear stability should be determined by standardized apparatus extending current testing of 30 to 90 cycles of oil passing through the nozzle. The paper presents the shear stability testing of most important types of commercial viscosity index improvers on Orbahn diesel injector apparatus at extended shear stability test (90 cycles) with aim on meeting the new engine oil specifications.
Motor oils constitute a group of lubricants whose significance is constantly growing with motor industry development, constituting the largest amount of lubricant consumption. Their quality is ...defined by classification per viscosity and specifications per performances. The classification defines motor oil low temperature properties by the highest dynamic viscosity at low temperature cold start and by the highest oil pumping dynamic viscosity at low temperatures. The said properties are checked by the Cold Cranking Simulator (CCS) device i.e. by the Miny Rotary Viscometer (MRV) device. In the latest edition of the SAE J300 classification from February, 2000, new, 5 0C lower temperatures have been introduced for identifying dynamic viscosity with the CCS device, as well as new dynamic viscosity limits. In keeping with these changes, (CCS) motor oil low temperature properties have been analyzed, showing that the motor oil formulations tested fully meet also the said classification's new requirements.
Motorna ulja predstavljaju grupu maziva ciji znacaj stalno raste s razvojem motorne industrije i cine najveci dio potrosnje maziva. Njihova kvaliteta definirana je klasifikacijom prema viskoznosti i ...specifikacijama prema radnim svojstvima. Klasifikacijom prema viskoznosti SAE J300 niskotemperaturna svojstva motornih ulja definirana su najvecom dinamickom viskoznoscu pri pokretanju motora kod niskih temperatura i najvecom dinamickom viskoznoscu pumpanja ulja kod niskih temperatura. Navedena svojstva odre|uju se na Cold Cranking Simulator (CCS) uredaju odnosno Mini Rotary Viscometer (MRV) uredaju. U najnovijem izdanju klasifikacije SAE J300 iz velja~e 2000. godine uvedene su nove za 5 °C nize temperature za odredivanje dinamicke viskoznosti na CCS ure|aju i nove granice dinamicke viskoznosti. U skladu s tim promjenama analizirana su niskotemperaturna svojstva motornih ulja (CCS) koja su pokazala da ispitivane formulacije motornih ulja u potpunosti zadovoljavaju i nove zahtjeve navedene klasifikacije.
ACEA SPECIFIKACIJE MOTORNIH ULJA Podobnik, Marijan; Bambic, Josip; Marinko Orsic
Goriva i maziva,
02/2002, Letnik:
41, Številka:
1
Journal Article
Odprti dostop
ACEA (Association des Constructeurs Européens d'Automobiles) predstavlja udruzenje europskih konstruktora vozila, koje je 1991. godine naslijedilo prijasnji CCMC (Comité des Constructeurs ...d'Automobiles du Marché Commun) i preuzelo CCMC-ove specifikacije. Prve ACEA specifikacije za motorna ulja izdane su krajem 1995. godine pod oznakom ACEA European Oil Sequences 1996. Specifikacije definiraju minimalne kvalitetne razine motornih ulja za servisno punjenje benzinskih motora, lako opterecenih dizelovih motora (osobna vozila) i tesko opterecenih dizelovih motora (gospodarstvena vozila). ACEA specifikacije zahtijevaju da su svi rezultati motornih ispitivanja primjenskih karakteristika ulja dobiveni u skladu sa sustavom osiguranja kvalitete europskih motornih ulja - EELQMS (European Engine Lubricants Quality Management System). Nakon ACEA-e 1996. slijedila su nova izdanja specifikacija motornih ulja ACEA 1998. te zatim ACEA 1999. Najnoviji nacrt ACEA 2002. specifikacija motornih ulja (draft 7.1a) objavljen je u rujnu 2001. g. Sa stajalista proizvodaca motornih ulja ACEA specifikacije su donijele znacajne promjene u razvoju motornih ulja time sto su strogo definirale postupke ispitivanja pri promjenama ili baznog ulja ili poboljsivaca indeksa viskoznosti u formulaciji motornog ulja.
ACEA 2004 SPECIFIKACIJE Podobnik, Marijan; Bambic, Josip; Visnja Mihaljus Sklepic
Goriva i maziva,
10/2005, Letnik:
44, Številka:
5
Journal Article
Sazetak Krajem 2004. godine usvojene su nove ACEA 2004 specifikacije motornih ulja za cestovna vozila (ACEA-Association des Constructeurs Européens d'Automobiles). Najznacajniji razlozi uvodenja ...novih specifikacija bili su Euro 4 zahtjevi emisije ispusnih plinova koji su uzrokovali uvodenje novih sustava obrade ispusnih plinova motora. U odnosu na prethodne ACEA 2002, nove ACEA 2004 specifikacije uvele su sljedece bitne promjene: · dosadasnje grupe A i B za osobna vozila objedinjene su u zajednicku grupu A/B, · uvedena je nova grupa C za motore osobnih vozila sa sustavima za obradu ispusnih plinova, · u grupi E povucene su dvije i uvedene dvije nove specifikacije. U novo formiranoj grupi A/B definirane su cetiri specifikacije motornih ulja za benzinske i dizelove motore osobnih vozila A1/B1-04, A3/B3-04, A3/B4-04 i A5/B5-04. U odnosu na ACEA 2002 nije doslo do promjena zahtjeva kvalitete ulja vec samo spajanja dviju grupa. Nova grupa C uvedena je za benzinske i dizelove motore osobnih vozila sa sustavima za obradu ispusnih plinova. Unutar navedene grupe definirane su tri specifikacije motornih ulja C1-04, C2-04 i C3-04 cija kvaliteta odgovara specifikacijama A5/B5 odnosno A3/B4. Najbitnije kod ovih specifikacija je ogranicenje kolicine sulfatnog pepela, fosfora (P) i sumpora (S) motornog ulja radi stetnog djelovanja na sustave obrade ispusnih plinova. U grupi E povucene su iz uporabe specifikacije E3 i E5, a uvedene su nove E6-04 i E7-04. Specifikacija E6-04 definira kvalitetu ulja za motore gospodarskih vozila sa sustavom za obradu ispusnih plinova te takoder ima ogranicenje kolicine sulfatnog pepela, fosfora (P) i sumpora (S) motornog ulja, dok je specifikacija E7-04 zapravo poboljsana dosadasnja E5 specifikacija.
THE ACEA MOTOR OIL SPECIFICATIONS Podobnik, Marijan; Bambic, Josip; Marinko Orsic
Goriva i maziva,
02/2002, Letnik:
41, Številka:
1
Journal Article
ACEA (Association des Constructeurs Européens d'Automobiles) represents an association of European vehicle designers. In 1991, it has taken over the role of the former CCMC (Comité des Constructeurs ...d'Automobiles du Marché Commun), inheriting their specifications in the process. The first ACEA motor oil specifications were issued towards the end of 1995, marked as ACEA European Oil Sequences 1996. The specifications are defining minimal motor oil quality levels for the service filling of gasoline engines, light-duty diesel engines (passenger vehicles), and heavy-duty diesel vehicles (commercial vehicles). The ACEA specifications require that all the results of oil performances engine testing obtained be in keeping with the European Engine Lubricants Quality Management System (EELQMS). After ACEA 1996, new editions of the ACEA motor oil specifications followed in 1998 (ACEA 1998), and 1999 (ACEA 1999). The latest ACEA 2002 motor oil specifications draft (draft 7.1a) has been published in September, 2001. From the viewpoint of motor oil manufacturers, the ACEA specifications have brought considerable changes into motor oil development by strictly defining test procedures for changing either base oil or viscosity index improver in the motor oil formulation.
