Two tests were conducted: first in order to demonstrate Triol system capabilities, second – in order to estimate dual-fuel influence to engine durability.Test conditionsAt both tests Scania performed round trip coal-preparation plant-mine-coal preparation plant. First leg was without load, at the mine truck was loaded by coal and then trip back. 2 legs length is 70-80km, climbing from mine 3-5 km 15-20% angle off-road.
Straight part is broken hilly ground, 2 ridges between 2 river valleys crossing. All tests were done with the same driver, at the beginning round trip was performed using diesel fuel only, then dual-fuel round trip. Diesel fuel consumption, CNG consumption mileage were noted at each round trip.
Diesel fuel consumption was measured by calibrated metering pump (see picture below). Vehicle was stopped at even ground at the same place during whole tests, before first test fuel tank was filled full by pump (until fuel dropped from inlet), after round trip tank was refilled again and liters added became round trip consumption.
CNG consumption was calculated using pressure gauge value at the beginning and at the end of each trip, knowing cylinder volume CNG consumption was calculated later. Substitution coefficient, power and torque. At first tests we got 62% substitution coefficient, at second tests 12 trips average coefficient was 57%. Average load was 34tons.,
Drivers noted increased haulage a t dual-fuel regime, they described this as a possibility to run one gear up comparing with diesel regime under the same road conditionsDual-fuel influence to engine In order to estimate dual-fuel influence to engine it was overhauled after first test in order to perform second tests at virtually new engine. Mileage was 670 000km.
After second tests we ordered engine disassembling at Scania official service with pistons, seals and valves removing and analysis (see pictures below)
No pistons/valves wear-and-tear, no oil consumption at all.