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Final Report
Comparison of transport operations by tractors with different transmissions
with a focus on fuel efficiency in road transport
Landwirtschaftskammer Schleswig-Holstein
Fachbereich Land- und Energietechnik
Grüner Kamp 15-17
24768 Rendsburg
2
Table of Contents
1st Introduction ........................................................................................................ 3
2nd Material and Methods ........................................................................................ 4
2nd1 Region of the study .................................................................................... 4
2nd2 Tractors/transmissions examined ............................................................... 5
2nd3 Load simulation .......................................................................................... 9
2nd3.1 Practice-reflecting test stand ............................................................... 9
2.3.2 Trailers .................................................................................................. 10
2nd4 Fuel consumption ..................................................................................... 10
2nd5 Data logger and data evaluation .............................................................. 11
2nd6 Influence of the drivers ............................................................................. 12
3rd Results .............................................................................................................. 13
3rd1 Engine brake ............................................................................................ 13
3rd2 Transport comparison .............................................................................. 18
3rd2.1 Travel speed ...................................................................................... 18
3rd2.3 Fuel/Ad-Blue consumption ................................................................. 20
3rd2.3 Fuel temperature ............................................................................... 22
3rd3 Cost consideration.................................................................................... 23
3rd4 Driver survey ............................................................................................ 25
4th Summary ........................................................................................................... 26
List of references .................................................................................................... 29
Annex....................................................................................................................... 30
3
1st Introduction
Agricultural transport in Germany accounts for more than 400 million metric tons a
year. The goods transported are extremely diverse, ranging from seed to mineral
fertilizers or harvested crops, and the average distance covered per trip is 3.91
kilometers.
The demands made of modern tractors for agricultural transport are of particular
significance. They comprise high speeds on the road, coupled with good accelerating
and braking performance, as well as good power transmission in the field – and the
tractors must be easy to operate and provide a comfortable ride.
Judging by the new registrations of tractors in Germany in the year 2011, it is
possible to identify a trend toward larger machines, especially in the category of 190
hp plus (VDMA, 2012). Ultimately, however, it is true here too that only the unit costs
count and the more efficiently the fuel/liquid is used, the lower the costs. By
comparison with the preceding year (2010), the tractor market in Germany with
35,977 new registrations grew by 26 percent in 2011. The demand for tractors is
supported by good income development in agriculture. According to the data
supplied by the European statistics authority Eurostat (2012), incomes of German
farmers increased by 15 percent per individual worker in 2011. There were special
influences additionally affecting the tractor market, such as the successive change in
engine technology to satisfy new exhaust standards.
Except on uphill and acceleration stretches, a tractor engine is not required to
operate at full load. That is why tractor manufacturers offer 50 km/h variants that
allow transportation at a travel speed of 50 km/h using lower engine speed with better
engine utilization. If the maximum speed of 50 km/h is maintained during transport,
this transmission variant does not save any time, but it does save diesel. This
transmission/engine control has become established among nearly all manufacturers
in recent years and there is customer demand for it. The efficiency of the
transmission and the electronic engine control in particular have a lasting effect on
the costs per transport kilometer.
This study on behalf of John Deere Werke Mannheim aims to compare different
tractor/transmission/engine controls under practical conditions. The question of the
efficiency of various transmissions (continuously variable or powershift) is to be
examined with regard to fuel consumption (diesel and Ad-Blue) and average speed,
under different load conditions in road traffic.
4
2nd Material and Methods
The methods and equipment used to capture the data are described below.
2nd1 Region of the study
The region in which the study was carried out is located in Rhineland-Palatinate,
southwest of Kaiserslautern (see Figure 1).
Figure 1: Region in which the comparison was carried out, southwest of Kaiserslautern (Google Earth, 2012)
The route runs through rural areas and passes through a number of towns and
villages in which various traffic-related influence parameters have an effect on the
test. Road junctions, traffic lights and pedestrian crossings have a traffic-restraining
effect and are accepted as given features during the test, just as are the weather
conditions (rainfall, temperatures etc.). Specifically reducing these influences was an
essential goal of the study, achieved by having a driver cover the same route four
times.
5
The following Figure 2 shows the course of the route in detail, as well as the altitude
profile to illustrate the route characteristics.
Figure 2: Route profile in the area examined southwest of Kaiserslautern (Google Earth, 2012)
The route profile shown in Figure 2 is 41.2 km long and four trips were made for each
case. The altitude difference (related to mean sea level) in the terrain is 268 m as a
minimum and 449 m as a maximum. The maximum gradient in the terrain profile is
~13.0 %.
2nd2 Tractors/transmissions examined
The tractors examined originate from various manufacturers and belong to the
performance category > 154 kW power rating (97/68EC). All four tractors examined
are owned by the John Deere factory and each had run for about 300 operating
hours when they joined the test. The following descriptions are oriented to the
manufacturers’ data on the internet.
6
Fendt 724 –Vario
The Fendt Vario transmission is a hydrostatic-mechanical power split drive. With
increasing speed the share of mechanical output transmitted via the planetary set
increases. The hydrostats, which can be swung through 45 degrees, and the high
operating pressure of at most 550 bar ensure the degree of efficiency.
In the Fendt 724 Vario the continuously variable transmission ML180 ensures the
correct gear ratio. The TMS Tractor Management System is used to keep the tractor
operating at the cost-effective optimum at all times. The driver enters the desired
speed and the activated TMS takes over the engine and transmission control. For
example, TMS ensures that the tractor drives at reduced engine speed on level
terrain. On hillsides, when the load increases, TMS automatically increases the
engine speed. Accordingly the tractor is always powered with the engine speed
reduced as far as possible. The test machine is equipped with a maximum output
control. Depending on the load, the maximum output control regulates the travel
speed dependent on the engine speed. There are different optimal load limit values
for various operations, for example transport or work on the field. The tractor
automatically sets the ideal load limit. This saves the driver from having to set the
maximum output control on arrival on entering or leaving the field. Consequently, the
interplay between engine and transmission is right for every application. Optionally
the driver can also set the maximum output control manually. This function was de-
activated for the comparison.
Fendt works with the SCR exhaust technology to reduce pollutants. In SCR
technology the exhaust gas is after-treated with Ad-Blue, a 32.5 percent urea
solution, and the nitrous oxides NOx are converted to non-toxic nitrogen and water.
The consumption of the urea-water solution that is used as standard in the
commercial vehicles sector is on average seven percent of the diesel consumption.
This can vary depending on the assignment and the load situation.
New Holland T7.270 -Auto Command
The T7 tractors with Tier 4A ECOBlue SCR advantage exhaust gas technology have
a higher output, as the combustion process is controlled better and the engine is set
more sharply – in other words it is run at higher temperatures.
7
The T7 tractors are equipped with an FPT industrial motor with ECOBlue SCR
exhaust gas technology. The Auto Command transmission used by New Holland is a
continuously variables transmission.
This generation of continuously variable transmissions has a number of different
driving modes (high mechanical efficiency) and an advanced double clutch control
system. The Auto Command transmission provides the option of setting a target
speed between 20 km/h and 50 km/h, no steps, no range changes – uniform
acceleration with seamless transmissions. New Holland has designed its Auto
Command transmission in such a way that the high torque of the engines is optimally
exploited.
John Deere 6210R –AutoPowr
The Motor PowerTech PVX engine combines cost-efficiency with power
development. In order to comply with the strict Tier IIIb exhaust gas standards, a
diesel-oxidation catalytic converter (DOC) is used together with a diesel particulate
filter (DPF). Here the re-circulated exhaust gas cools a part of the exhaust gasses
before they are passed back into the incoming air on the intake side. Through the
lower exhaust gas temperatures, the NOx shares are reduced, but more soot
particles are produced and these are collected in the particulate filter. This filter has
to be cleaned (regenerated) from time to time (at the latest after 25 h). For this, a
small amount of fuel is injected into the filter (<1%) for combustion of the particles in
the DPF. The 6R series builds on proven technology. The output, efficiency and
flexibility of this tractor series has been improved further according to the information
supplied by the manufacturer. The AutoPowr transmission offers automatic infinitely
variable control of the transmission ratio in order to maintain the set forward speed,
while at the same time reducing the engine speed and the diesel consumption. The
100 percent mechanical power at 4, 8, 20 and 40 km/h reported by the manufacturer
means high efficiency both on the field and at transport speed.
John Deere 6210R –DirectDrive
The DirectDrive transmission is used in the JD 6210R DD. The semi-automatic 8-
gear dual clutch transmission is characterized by high shifting speeds.
8
By increasing the number of powershift gears to eight, this transmission reduces the
need for range shifting, which leads to fewer torque interruptions. It is possible to
either drive completely automatically or to select one of three ranges for the task
ahead.
The following table shows the technical information for all four tractors that is
essential for the comparison.
Table 1: Essential technical data of the tractors used
Fendt 724
Vario
New Holland T7.270
Auto Command
John Deere 6210R
AutoPowr
John Deere 6210R
DirectDrive
Output [hp]*
237 hp (97/68 EC)
261 hp (EPM (ECE R120))
240 hp (IPM(97/68EC))
240 hp (IPM(97/68EC))
Weight [kg] 7950 8825 8760 8625
Power-weight ratio [kg/hp]
33 34 37 36
Tires front (1.8 bar air pressure)
540/65R30 Trelleborg
600/60R30 Michelin
600/70R28 Michelin
600/70R28 Michelin
Tires rear (1.6 bar air pressure)
650/65R42 Trelleborg
710/60R42 Michelin
710/70R42 Michelin
710/70R42 Trelleborg
Transmission* continuously
variable
continuously variable,
dual clutch transmission
continuously variable
dual clutch transmission
Exhaust gas technology*
SCR SCR Exhaust gas
recirculation with particulate filter
Exhaust gas recirculation with particulate filter
*Manufacturers’ information
Table 1 shows that the Fendt 724 Vario is the lightest of the four tractors and offers
the best tires for the planned measurements in practice as regards contact area and
rolling resistance. The New Holland has the highest output. The John Deere 6210R
AutoPowr has the highest power-weight ratio, followed by the John Deere
DirectDrive, New Holland T7.270 and Fendt 724 Vario.
Higher power-weight ratios are important above all for the heavy pulling work, for
example during tillage operations, but more of a disadvantage for road transport.
9
2nd3 Load simulation
Various measuring methods were used for the comparison. On the one hand each
tractor was measured in the practice-reflecting test stand with an eddy-current brake
at the PTO shaft, and on the other hand each tractor was driven along the transport
route already described, four times with a trailer and four times without (cf. Figure 2).
The tractors were all ballasted with a front weight of 900 kg for these comparative
transport measurements.
2nd3.1 Practice-reflecting test stand
The measurements on the test stand were carried out with a mobile eddy-current
brake fabricated by Messrs. Eggers (Type: PT302). The speed, output and torque at
the PTO shaft were measured for each tractor. The consumption was measured
volumetrically with the sensor FM 3-100.
Figure 3: Test stand measurement – eddy-current brake “Eggers Dynamometer” at the
PTO shaft
The engine brake connected to the PTO shaft shown in Figure 3 captures and
records the torque and the output of the tractor over the entire engine speed range.
The engine characteristics measured serve as a basis for the following comparative
transport measurements on the road.
10
2.3.2 Trailers
The actual test, on which the economic evaluations too are subsequently based, was
carried out on the road. To reduce traffic-related influences on the speed and
consumption, the route was travelled eight times by each tractor with each driver.
Four trips were made without a trailer and four trips with a loaded trailer.
For this purpose two Krampe dumpers were loaded with gravel so that they reached
a total weight of 18 tons. The two trailers of the same design were equipped with
different tires, as shown in the following table.
Table 2: Krampe dumpers used for the transport comparison test
The two dumpers have different tires and are operated with the optimal air pressure
for the total weight. This leads to different rolling resistances that could influence the
results. For this reason all the tractors were each driven along the route twice with
the Krampe 1 trailer and twice with the Krampe 2 trailer.
2nd4 Fuel consumption
The fuel consumption was determined volumetrically during the test stand
measurements. For this the sensor FM 3-100 belonging to the engine brake was
installed on the tractor’s own forward and reverse.
Figure 4: Volumetric fuel sensor at the test stand measurement
Krampe 1 Krampe 2
Tires Trelleborg Twin Radial
680 / 55 R 26,5 Michelin Cargo X Bib
600 / 55 R 26,5
Air pressure [bar] 3.4 4.0
Total weight [t] 18 18
11
For the measurements of the transport trips, each tractor was filled up with diesel and
Ad-Blue prior to the start and the liquid volume and filling level were documented.
After four trips in each case – in other words 164.8 kilometers – the tanks were
topped up again. A Horn fuel pump with meter was used for this. The Ad-Blue
consumption was recorded on topping up, using a 2 l measuring beaker with an ml
scale.
For the test stand measurements and the transport measurements the fuel
temperature was measured with an IR thermometer at the beginning and the end.
The IR thermometer used was a Voltcraft IR900-30s.
2nd5 Data logger and data evaluation
The tractors were equipped with GPS data loggers for the transport comparison in
order to record the actual speed over ground and altitude automatically.
Data loggers of the firm ASUS MyPal 365 were used for this purpose. The GPS
software “Field Rover II” in version 10.6 was installed in them. The systems work with
the EGNOS correction data signal, and depending on the reception conditions are
precise up to ± 30 cm. In addition to the position, they also supply data on the GPS
speed, the altitude and the course. Accordingly, the routes could be recorded as
“path” and used for further evaluations.
The following must be mentioned for a comparison of the speeds measured. Some
tractors (Fendt 724 Vario and John Deere 6210R AutoPowr) are equipped with an
electronic speed limitation that cuts in electronically at speeds of more than 50 km/h.
The other two tractors (New Holland T7.270 and John Deere 6210R DirectDrive) do
not have this automatic limitation integrated, so that on downhill stretches they
reached speeds of up to 60 km/h, which led to higher average speeds.
12
2nd6 Influence of the drivers
The driver of a machine is considered to be a main parameter influencing its capacity
utilization and efficiency of use. To reduce this influence on the test result, four
different drivers were deployed at the same time, so that each driver made the trips
with each tractor and each trailer. This makes it possible to ensure that the influence
of the driver is reduced to a negligible minimum. All four drivers are technically very
experienced staff of farm contractors and have many years of experience in
transporting agricultural goods in road traffic.
13
3rd Results
The comparison was carried out in calendar week 29 (2012) on the test section
southwest of Kaiserslautern. The results are set out below.
3rd1 Engine brake
At the start of the test all four tractors were examined with the mobile practice-
reflecting test stand. For this the engine brake was connected to the PTO shaft and
the volumetric fuel sensor installed on the respective tractors.
This test in the mobile practice-reflecting test stand serves as a starting point and the
engine characteristic data recorded serve as a basis for the transport comparison.
Figure 5 shows a screenshot of the measurements on the Fendt 724 Vario. All output
measurements relate to hp and hour. The factor 0.7534 is used to convert them into
kW.
Figure 5: Screenshot of the output/torque curve and the specific fuel consumption in the speed range of the Fendt 724 Vario on the mobile practice-reflecting test stand at a diesel temperature of 20 °C
For the Fendt, the output curve runs uniformly upwards up to an engine speed of
1800 rpm. The maximum output of 221.1 hp is achieved at 1750 revolutions, which
represents a difference of -18.9 hp by comparison with the stated output of 240 hp
(ECE-R24 max.).
14
The torque curve reaches its maximum (950.6 Nm) at 1400 revolutions and then
drops uniformly to the rated speed of 2100 revolutions.
The following figure shows a screenshot of the measurement table during the
measurements on the mobile practice-reflecting test stand.
Figure 6: Screenshot of the measurements of the Fendt 724 Vario on the mobile practice-reflecting test stand at a diesel temperature of 20 °C
The measurements in Figure 6 show that the maximum torque is reached at 1397
engine revolutions. The maximum output for the Fendt 724 Vario given as 240 hp is
not reached, as at 1750 engine revolutions a maximum output of 221.1 hp was
determined on the mobile practice-reflecting test stand – highlighted in yellow. As this
was measured at a diesel temperature of 20 °C – in other words with relatively cold
diesel – the measurement was repeated later at distinctly higher diesel temperatures
(see Annex 1 and Annex 2).
Figure 7 shows the output/torque curve of the John Deere 6210R with the DirectDrive
transmission newly presented in 2011.
15
Figure 7: Screenshot of the output/torque curve and the specific fuel consumption in the speed range of the John Deere 6210R - DirectDrive in the mobile practice-reflecting test stand at a diesel temperature of 35 °C
The torque curve fluctuates strongly at the beginning; as of 1650 engine revolutions it
drops continuously up to the rated torque at approx. 2150 engine revolutions. The
output curve rises continuously, and as of 1800 engine revolutions reaches almost
constant output that does not exceed 234.1 hp, representing a difference of -5.9 hp
compared with the stated output. The specific fuel consumption reaches its minimum
of approx. 159 g/hph at 1400, 1750 and 2180 engine revolutions. The torque
increase is 13.66% and thus reaches the highest value of all four tractors examined.
The measurement results were obtained at a diesel temperature of 35 °C, which
represents the second lowest temperature of all mobile test stand measurements
conducted in this survey.
The following Figure 8 shows the measuring results over the entire speed range of
the John Deere 6210R – DirectDrive. The line with the maximum output is highlighted
yellow.
16
Figure 8: Screenshot of the measurements of the John Deere 6210R - DirectDrive in the mobile practice-reflecting test stand at a diesel temperature of 35 °C
Altogether the John Deere 6210R – DirectDrive – only reaches its maximum engine
output of 234.1 hp at higher speeds than the Fendt 724 – Vario. The associated
higher fuel consumption rates than for the Fendt or New Holland are the
consequence, as Figure 8 and the following
Table 3 show.
Table 3: Comparison of the results of all four tested tractors at maximum measured
output in the mobile practice-reflecting test stand
Fendt 724
Vario
New Holland T7.270
Auto Command
John Deere 6210R
AutoPowr
John Deere 6210R
DirectDrive
237 hp
(97/68 EC) 261 hp
(EPM (ECE R120)) 240 hp
(IPM(97/68EC)) 240 hp
(IPM(97/68EC))
Max. power [hp] 225.2 230.4 239.2 234.1
Engine speed [/min] 1697 1748 1945 1951
Torque [Nm] 883.7 885.5 821.4 798
Consumption [l/h] 43.2 46.8 46.8 50.4
spec. consumption [g/PSh] 162.1 171.7 165.3 182.0
Diesel temperature [°C] 53 39 32 35
17
*measured without boost in the test stand, is activated automatically by the New Holland as of 15.5 km/h
The lowest specific fuel consumption at maximum output is achieved by the Fendt
724 Vario, as shown in Table 3. The Fendt reaches its maximum measured output
already at 1697 engine revolutions per minute, while the John Deeres only reach
their maximum output at 245 revolutions more and thus consume more fuel.
However, at 225.2 hp the Fendt falls short of the stated output by -14.6 hp. Without
the boost the New Holland lies in the output range stated by the manufacturer, and
the John Deeres lie within the acceptable tolerance range around the stated value at
maximum output on the mobile practice-reflecting test stand.
The torques measured at maximum output range from 885.5 Nm (New Holland) to
798.0 Nm (John Deere DirectDrive). The two continuously variable transmissions in
the Fendt and John Deere reach their maximum torque at around 1400 engine
revolutions per minute, and the New Holland only at 1500 revolutions per minute.
It is conspicuous that the diesel temperatures are very high for the measurements on
the mobile practice-reflecting test stand, above all for the Fendt at 53 °C, as the other
three tractors lie between 32 and 39 °C. This indicates that perhaps the reason why
the Fendt 724 Vario does not reach its stated maximum output of 240 hp lies here. In
the trade there is talk of a 2.5% reduction in output per 10°C higher diesel
temperature, see Annex 12 (Eggers, 2006; Lindemann, 2012).
Continued - Table 3: Comparison of the results of all four tested tractors at maximum measured output in
the mobile practice-reflecting test stand
Fendt 724
Vario
New Holland T7.270
Auto Command
John Deere 6210R
AutoPowr
John Deere 6210R
DirectDrive
237 hp (97/68 EC)
261 hp (EPM (ECE R120))
240 hp (IPM(97/68EC))
240 hp (IPM(97/68EC))
Max. torque [Nm] at engine speed [/min]
960.1 1397
977.4 1497
910.5 1390
907.0 1402
18
3rd2 Transport comparison
3rd2.1 Travel speed
The travel speed as essential measuring parameter for the transport performance in
road traffic was measured continuously every second by the GPS data logger (see
Chapter 2nd5).
Figure 9 shows the data stored for a measured trip by the New Holland T7.270 Auto
Command by way of example.
Figure 9: Actual speed in the altitude profile for the New Holland T7.270 Auto Command
Above all the speeds of over 50 km/h are notable here. These are possible with this
tractor, as with the John Deere 6210R DirectDrive, because the dual clutch
transmission is not braked electronically, as is the case with the other two test
tractors (Fendt 724 Vario and John Deere 6210R AutoPowr).
The following Figure 10 shows the influence of the driver on the average speed in the
transport comparison test.
19
Figure 10: Influence of the driver on the average speed, taking the New Holland T7.270 Auto Command and John Deere 6210R AutoPowr as examples
For the purpose of this study, four drivers were deployed on each of the tractors and
with each loading condition. The two tractors selected in the figure above initially
show a different speed level. The John Deere was altogether faster than the New
Holland.
The boundary difference (5 %) of 1.47 km/h makes it clear that despite the different
average speeds reached, the drivers are absolutely comparable within one tractor
type and do not display any significant differences. However, the differences between
the tractor types shown in Figure 10 are significant.
That is why in the further considerations we always calculated with the average
speed of the four drivers for the respective tractors, which is shown in Figure 11.
20
Figure 11: Average speed of the four drivers per tractor calculated/obtained
The average speeds shown indicate a clear trend. Despite the better weight and the
narrower tires for road transport (= lower rolling resistance), the Fendt achieved the
lowest speed (37.7 km/h). The New Holland and the John Deere 6210R DirectDrive
follow this. The highest speed of 43.8 km/h is achieved by the John Deere with
continuously variable AutoPowr transmission. The boundary difference of 1.8 km/h
indicates with an error probability of 5% that the differences between Fendt and New
Holland in this survey are not significant, just like the differences between the two
John Deeres. However, the difference between the leading group – the two John
Deeres – and the other two tractors from Fendt and New Holland is significant.
3rd2.3 Fuel/Ad-Blue consumption
The diesel fuel and Ad-Blue consumption measured as a further key component for
the efficiency comparison between the four tractors is considered more closely
below. For this purpose the filling levels of each fluid were determined during the
tests and supplemented by topping up before each change of driver or load condition
(see Chapter 2nd4).
21
Table 4 shows the consumption rates of diesel fuel and Ad-Blue measured in the
experiment for the different load situations.
Table 4: Diesel and Ad-Blue consumption at different load situations
Fendt 724 Vario
New Holland T7.270 Auto Command
John Deere 6210R Autopowr
John Deere 6210R
DirectDrive
237 hp
(97/68 EC) 261 hp
(EPM (ECE R120)) 240 hp
(IPM(97/68EC)) 240 hp
(IPM(97/68EC))
Full trip
Total diesel [l] 531.00 507.00 539.00 499.00
Liter Diesel je km 0.809 0.773 0.822 0.761
Liter Ad-Blue je km 0.036 0.042 0.000 0.000
Total [l/km] 0.846 0.815 0.822 0.761
Empty trip
Total diesel [l] 283.00 282.00 322.00 287.00
Liter diesel per km 0.431 0.430 0.491 0.438
Liter Ad-Blue per km 0.024 0.021 0.000 0.000
Total [l/km] 0.455 0.450 0.491 0.438
Total [l/km] 0.651 0.633 0.656 0.599
The expectation that SCR tractors display lower diesel consumption rates cannot be
confirmed by the data in Table 4. If one considers the trips with high pulling load = full
trip (trailer with 18 t total weight), it becomes apparent that the Fendt displays the
highest consumption (0.846 l/km) of diesel and Ad-Blue, followed by the John Deere
with continuously variable AutoPowr transmission, then the New Holland, and finally
the John Deere with DirectDrive transmission (0.761 l/km). The volumetric Ad-Blue
consumption by the Fendt in loaded condition amounts to 4.5% of the diesel
consumption, and for the New Holland 5.4% of the diesel consumption, and is thus in
the anticipated range. The manufacturers’ data state that the Ad-Blue consumption
depends on the load and can be between 2 and 7% of the diesel consumption. On
empty trips the Ad-Blue consumption should drop, but it only does this with the New
Holland – to 4.8%. With the Fendt, it rises from 4.5% to 5.6% of the diesel
consumption, which was not expected. This may be attributable to the high diesel
temperatures, as these influence the performance capability of the Fendt as shown in
Chapter Fehler! Verweisquelle konnte nicht gefunden werden..
The average fluid volume consumed as a mean value for both empty and full trips
shows that the John Deere with the DirectDrive transmission displays the lowest fluid
consumption of 0.599 l/km, followed by the New Holland, the Fendt and the John
Deere with AutoPowr transmission (0.656 l/km).
22
3rd2.3 Fuel temperature
The fuel temperature could be the essential parameter influencing the performance
capability of the tractors. The trade experts (Eggers, 2006; Lindemann, 2012)
assume an output reduction of 2.5% per 10°C higher diesel temperature. That is why
at the end of all the trips the diesel temperatures in the tank were determined.
The following figure shows the mean fuel temperatures for each tractor.
Figure 12: Diesel temperature at the end of the full trip in road transportation, mean value for all four drivers
Generally the trend indicated on the mobile practice-reflecting test stand
measurements (see Section Fehler! Verweisquelle konnte nicht gefunden
werden., p. Fehler! Textmarke nicht definiert.) was continued in road transport too.
However, there were also some changes – for instance the John Deere with
AutoPowr transmission at 37.8 °C now has higher diesel temperatures (+5.8 °C) than
on the test stand, while the DirectDrive displays exactly the same temperature as it
did for the test stand measurement. The New Holland with an average of 45.6 °C
shows the highest temperatures in transport, followed by the Fendt with 42.8 °C and
the John Deere AutoPowr with 37.8 °C. The two John Deere tractors are equipped as
standard with a fuel cooler, while the Fendt and the New Holland are not.
23
If the output reduction of 2.5% is to be expected on the grounds of the higher diesel
temperatures, then the output by comparison with the manufacturer’ data would
change as follows (see Figure 13).
Figure 13: Output and output shortfall by comparison with the manufacturers’ data as a function of the diesel temperature during transport (Index John Deere 6210R-DirectDrive = 100)
The output reduction due to the higher temperature of the diesel is then calculated at
7 hp for the New Holland, so that ultimately 253 hp are achieved instead of the stated
260 hp. The output reduction for the Fendt using this approach is 5 hp, for the John
Deere AutoPowr 2 hp, and the John Deere DirectDrive does not display any output
cuts as it is the reference value.
3rd3 Cost consideration
The costs of diesel fuel and Ad-Blue are to be considered as key components of the
efficiency considerations for this study.
The purchase prices for diesel fuel and Ad-Blue urea solution (without value added
tax) were used for the consideration of costs. The consumption rates already shown
in Section 3rd2.3 (see Table 4) for different load situations were also used. The cost
calculations for the consumption rates measured in the practical test are shown in
Table 5.
24
Table 5: Cost calculation for diesel and Ad-Blue for the consumption rates measured in various load situations
Fendt 724 Vario
New Holland T7.270 Auto Command
John Deere 6210R Autopowr
John Deere 6210R
DirectDrive
237 hp
(97/68 EC) 261 hp
(EPM (ECE R120)) 240 hp
(IPM(97/68EC)) 240 hp
(IPM(97/68EC))
Full trip
Total diesel [l] 531 507 539 499
Liter per km 0.809 0.773 0.822 0.761
Liter Ad-Blue per km 0.036 0.042 0.000 0.000
Euro / km diesel*² 1.003 0.957 1.018 0.942
Euro/km Ad-Blue*³ 0.029 0.033 0.000 0.000
Total [€/km] 1.03 0.99 1.02 0.94
Empty trip
Total diesel [l] 283 282 322 287
Liter per km 0.431 0.430 0.491 0.438
Liter Ad-Blue per km 0.024 0.021 0.000 0.000
Euro / km diesel*² 0.534 0.532 0.608 0.542
Euro/km Ad-Blue*³ 0.019 0.016 0.000 0.000
Total [€/km] 0.55 0.55 0.61 0.54
Grand total [€/km] 0.79 0.77 0.81 0.74
rel. costs* 101.70 98.77 104.31 95.22
* Index 100 = Average total costs of all tractors
*² Diesel: 1.2385 €/l without VAT
*³ Ad-Blue: 0.795 €/l without VAT
The calculation of costs for the individual tractors was carried out separately for
empty trips and loaded trips, as well as in the form of an equally-weighted mean
value from the two conditions. It becomes apparent that at full load the John Deere
DirectDrive at 0.94 €/km lies ahead of the New Holland, the John Deere AutoPowr
and the Fendt (1.03 €/km). This trend is not reflected in the same way for the empty
trips. Here the Fendt and the New Holland at 0.55 €/km lie in joint second place. The
mean value of the two load situations produces a trend similar to that for the full trips.
The worst consumption rate is obtained by the John Deere with AutoPowr
transmission, followed by the Fendt and the New Holland, and finally the John Deere
with DirectDrive comes out best at 0.74 €/km.
If the mean value of all four tractors is assumed to be 100, in relative terms the John
Deere DirectDrive at 4.78 % is better than the mean value, as is the New Holland
with 1.23 % points. The Fendt is 1.70 % worse than the mean value and the John
Deere AutoPowr 4.31 %. This produces a range of 9.1 % points between the best
and the worst tractor.
25
3rd4 Driver survey
The driver survey was carried out with a standardized questionnaire (see Annex).
Each driver completed this directly after his trip with the respective tractor. The
categories relevant for this comparison are shown in the following table.
Table 6: Result of the driver survey in the categories engine, transmission and overall impression, using the German school grading system (1 = high, 5 = low) with number of entries and average grade
Vehicle Fendt 724 Vario New Holland T7.270
Auto Command John Deere 6210R
AutoPowr John Deere 6210R
DirectDrive
Grade 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5
Engine 2.2 2.4 1.8 1.8
Performance impression 3 1 1 2 1 1 3 1 3
Noise 1 1 2 1 2 1 1 3 1 3
Maintenance points 1 2 1 2 2 1 2 1 1 2 1
Number 2 6 4 0 0 2 4 5 1 0 3 8 1 0 0 3 8 1 0 0
Transmission 1.8 3.2 2.3 2.5
Ease of shifting 1 3 2 2 3 1 2 2
Noise 1 1 1 1 1 1 2 1 3 1 2 1
Aut. programming 2 2 3 1 1 2 1 1 2 1
Reverse shifting 1 3 2 2 1 1 3 3
Displays 4 1 2 1 1 2 2 1 3
Number 9 9 1 0 1 1 3 10 7 1 6 9 0 3 2 4 7 1 1 2
Overall assessment 2.2 2.5 1.9 2.1
Engine 3 1 1 2 1 1 3 1 3
Chassis 1 3 3 1 1 3 1 3
Transmission 2 1 1 1 2 1 1 3 1 2 1
Lift unit/hydraulics 1 1 1 1 1
Cab 2 1 1 1 3 1 2 1 1 1 1 1
Number 3 10 2 2 0 2 6 7 2 0 4 11 2 0 0 4 10 3 1 0
The average grades for each tractor and for the relevant categories of the driver
survey questionnaire display a partly very heterogeneous picture.
In the engine category the two John Deeres each achieve a grade of 1.8 and thus lie
in the “good” range. This rating is attributable to the high average speeds achieved in
the transport comparison. The drivers give the Fendt a grade of 2.2, so that it is still in
the “good” range, as is the New Holland with the grade 2.4.
26
In the transmission category the drivers assessed the Fendt 724 – Vario best with the
grade 1.8, followed by the John Deere AutoPowr with a grade of 2.3. The drivers give
the semi-automatic dual clutch transmission (DirectDrive) from John Deere 0.2 grade
points less than the AutoPowr transmission. The John Deere is followed by the New
Holland with the grade 3.2.
Both John Deeres are given the grade five more than once for the poor display
position. The drivers add that the reasons for the 3.2 in the New Holland were an
intricate, complicated menu navigation and a cruise control that could not be used.
In the overall assessment by the drivers the two John Deeres take first and second
position. The ranking in the survey puts the John Deere 6210R AutoPowr ahead of
the DirectDrive, followed by the Fendt and the New Holland. The heterogeneous
assessment pattern for the Fendt and the New Holland is particularly striking. This is
due above all to the low transport speeds achieved by the Fendt and small deficits in
the operability/comfort (menu navigation in the display, lack of cruise control) in the
New Holland.
4th Summary
The transport comparison of four different tractors, transmissions and engine controls
in calendar week 29/2012 was carried out in order to determine their transport
efficiency in road transportation. For this purpose a route in the Rhineland Palatinate
southwest of Kaiserslautern was used and travelled with different load conditions
(empty trip, full trip).
One key question consisted of finding out how effectively the new semi-automatic
“DirectDrive” dual clutch transmission in the John Deere 6210R works. For this
purpose a comparison with the John Deere continuously variable AutoPowr
transmission, also in a 6210R, was carried out. In addition two further tractors built by
competitors, on the one hand a Fendt 724 Vario and on the other a New Holland
T7.270 Auto Command, were included in the comparison. Here too the Fendt is
equipped with a continuously variable Vario transmission and the New Holland with a
continuously variable double clutch transmission. In addition both tractors are
equipped with the SCR exhaust gas technology, while the John Deere machines are
equipped with exhaust gas recirculation and particulate filter in order to satisfy the
valid exhaust gas standards.
27
The additional Ad-Blue consumption was also captured during the tests in order to
subsequently be able to calculate the costs per kilometer driven.
First of all the actual condition of the four tractors was checked on the mobile
practice-reflecting test stand. The measurements on the mobile practice-reflecting
test stand using an eddy-current brake of type Eggers Dynamometer displayed initial
differences between the tractors. For instance the Fendt could not achieve its stated
output of 240 hp, but instead only managed 225.2 hp. This difference of -14.8 hp was
reflected in the transport comparison on the road with a 13% gradient, for here the
Fendt only achieved the lowest average speeds.
In the opinion of the testers this output difference measured on the test stand is
crucially attributable to the higher diesel temperatures. The Fendt in particular had
very high temperatures of over 50 °C in the diesel here. During road transport these
temperatures were slightly lower thanks to the airstream.
The different transmission technologies and their efficiencies were revealed clearly
when it came to road transportation. The fast accelerations necessary for
transportation can be reached by fast shift operations. Here the dual clutch
transmission especially of John Deere displayed its strength, as is expressed in the
low consumption rates. The comfort of the semi-automatic transmissions can still be
improved. For example these aspects carried particular weight in the subsequent
survey of the drivers. The lack of cruise control, the complicated program steps and
unclear and overloaded menus are just some of the remarks made by the four drivers
in this comparison.
The result derived from the measurements described and the costs per kilometer
driven calculated from this shows that the dual clutch transmission means lower
costs of transportation. The continuously variable transmissions caused higher costs
here. In this study the John Deere 6210R DirectDrive came off best with 95.22 %, in
other words with 4.78 points below the average of the four tractors tested.
28
The New Holland T7.270 Auto Command with 98.77 % was the second best tractor,
remaining 1.23 % below the average. The third in this cost per kilometer
consideration is the Fendt 724 Vario, lying just above the mean value at 101.70 %.
Fourth place was taken by the John Deere 6210R AutoPowr with 104.31 %. This
represents a range of 9.1 percentage points between the best and the worst tractor.
The question of where the high diesel temperatures come from remains open in this
comparison. It is possible that especially in the Fendt and the New Holland,
supplementary temperature reduction measures will bring the required output. The
larger engine with more power in the New Holland additionally brings lower
consumption at the same output.
The measurements are one factor, the drivers’ impressions the other. Here,
especially in the transmission category – which was the specific subject of this test –
the Fendt came off best with a good grade of 2. The continuously variable AutoPowr
transmission, the semi-automatic DirectDrive and finally the Auto Command
transmission were graded by the drivers on average 0.2 points worse each.
It remains to be noted that the John Deere 6210R with DirectDrive delivered the best
measurement results. Especially for transportation with fully loaded trailers – as used
in this test – the semi-automatic transmission demonstrates its advantage on
sections with strong gradients. This advantage is further reinforced by the unthrottled
speed on downhill sections. The high kerb weight and the high-torque engines lead
to a positive overall assessment by the test team.
29
List of references
Eggers H., 2006: Bedienungsanleitung der Wirbelstrombremse für die Zapfwelle „Eggers PT02“, p. 30
Eurostat, 2012: Agricultural income.
http://epp.eurostat.ec.europa.eu/portal/page/portal/eurostat/home/, retrieved on 30.07.2012
Lindemann S., 2012: Influence of fuel temperature on power measurements at the
PTO. Owner of Dieseltechnik Lindemann GmbH in Osterrönfeld, oral
notification on 3.8.2012
VDMA , 2012: Tractor registrations 2011.
http://www.vdma.org/wps/wcm/connect/8f71db0044a51b958bcdaf9c93f511f4
/Zulassungen+2011.pdf?MOD=AJPERES&CACHEID=8f71db0044a51b958b
cdaf9c93f511f4, retrieved on 30.07.2012
30
Annex
Annex 1: Screenshot of the power/torque curve and the specific fuel consumption in the engine speed range of the Fendt 724 - Vario on the mobile practice-reflecting test stand at 53 °C
Annex 2: Screenshot of the measurements of the Fendt 724 - Vario on the mobile practice-reflecting test stand at 53 °C diesel temperature
31
Annex 3: Screenshot of the power/torque curve and the specific fuel consumption in the engine speed range of the Fendt 724 - Vario on the mobile practice-reflecting test stand at 20 °C diesel temperature
Annex 4: Screenshot of the measurements of the Fendt 724 - Vario on the mobile practice-reflecting test stand at 20 °C diesel temperature
32
Annex 5: Screenshot of the power/torque curve and the specific fuel consumption in the engine speed range of the New Holland T7.270 Auto Command on the mobile practice-reflecting test stand at 39 °C diesel temperature without boost
Annex 6: Screenshot of the measurements of the New Holland T7.270 Auto Command on the mobile practice-reflecting test stand at 39 °C diesel temperature without boost
33
Annex 7: Screenshot of the power/torque curve and the specific fuel consumption in the engine speed range of the John Deere 6210R - DirectDrive on the mobile practice-reflecting test stand at 35 °C diesel temperature
Annex 8: Screenshot of the measurements of the John Deere 6210R - DirectDrive on the mobile practice-reflecting test stand at 35 °C diesel temperature
34
Annex 9: Screenshot of the power/torque curve and the specific fuel consumption in the engine speed range of the John Deere 6210R - AutoPowr on the mobile practice-reflecting test stand at 32 °C diesel temperature
Annex 10: Screenshot of the measurements of the John Deere 6210R - AutoPowr on the mobile practice-reflecting test stand at 32 °C diesel temperature
35
36
Annex 12: Correction factors for the output measurement
(Excerpt from the operating instructions for the PTO “Eggers PT02”, p. 30)
- the legally admissible tolerance ± 5 % to DIN 70020 - acc. to ISO 1585 and SAE J 1349 the Visco-ventilator remains switched off
Fuel per 10°C
temperature -2.5 %
Intake air per 10°C
temperature -1.0 %
Air pressure per 10 mbar
atm -0.15 %
Fuel per 10 Kg / m3
density -1.2 %
Fuel per 1 cSt
viscosity -0.8 %