Variations in Exploitation Characteristics of Tractors Depending On Pre-Ignition Angle of the Engine

Abstract

Maintenance of tractors on small private farms in Bosnia and Herzegovina is not given sufficient and adequate attention. Consequences of such a trend reflect on exploitation characteristics of tractors, significantly increases fuel consumption and environmental pollution. The goals of the research focused on the part of the issue related to the influences of different pre-ignition angle of the engine on the available power at the PTO shaft and increase of the specific fuel consumption. The research was conducted in the laboratory and experimental facilities of the agricultural machinery testing station in 2015 at the Butmir range, Sarajevo. The obtained results indicate that the tractor power at PTO shaft varied from 21kW do 45kW, that is in a range from 46.6 - 100 %. Variation of the engine power caused changes in fuel consumption which in the plough mode varied from 4.01- 6.86 kg•h-1 of fuel (D-2). Cost-wise, this influenced variations from 2.25 to 4.72 €•h-1 in the idle mode (stand gas) and from 5.57 to 8.81€•h-1 in the plough mode. The obtained results confirmed the hypothesis that regular maintenance in accordance with manufacture’s standards needs to be implemented; otherwise the costs of consequences will exceed the maintenance costs several times.

Održavanju traktora na malim privatnim posjedima u Bosni i Hercegovini ne posvećuje se dovoljna pažnja. Posljedica takvog stanja odražava se na eksploataciona svojstva traktora, te značajno povećava potrošnju goriva i zagađenje okoline. Ciljevi istraživanja fokusiraju se na dio problematike koja sagledava uticaj različitog ugla predpaljenja motora na raspoloživu snagu traktora na priključnom vratilu (PTO) i povećanje specifične potrošnje goriva. Istraživanja su izvedena u laboratorijskim i eksperimentalnim uslovima ispitne stanice za poljoprivredne mašine u Sarajevu, na destinaciji “Poligona Butmir” u 2015. godini. Dobiveni rezultati ukazuju da je snaga traktora na PTO varirala u rasponu od 21kW do 45 kW, što u procentualnim pokazateljima iznosi 46,6 - 100 %. Varijacije snage motora prouzrokovale su promjenu potrošnje goriva koja je iznosila u oranju od 4,01- 6,86 kg•h-1 nafte (D-2), dok se navedena potrošnja goriva u finansijskim pokazateljima kretala u rasponu od 4,41 do 9,23 KM•h-1 na štandgasu i od 10,9 do 17,23 KM•h-1 u oranju. Dobiveni rezultati su potvrdili hipotezu da servisiranje poljoprivrednih traktora treba izvoditi redovno i prema tvorničkim normativima, u protivnom posljedice višestruko nadmašuju troškove servisiranja.