Test drive new Valtra A850R tractor

With 89 hp of power, the A850R is the new cab model of Valtra's A2R Series, a medium-sized tractor that stands out for the versatility that different operations in this power range require.

Even in this period of pandemic, with reduced working hours and many professionals working from home, companies are presenting new features in their lines of agricultural machinery. With a raw material supply crisis, managers have used creativity to launch new products that add to the brands' offering. To discover one of these launches, Revista Cultivar Máquinas moved its team to the city of Campinas, São Paulo, to see the Valtra brand tractor, model A850R, with 89 hp. 

Valtra's line of tractors in the country is made up of nine series and 40 models, ranging from small fruit tractors starting at 69 hp, to large tractors in the S4 Series, with the largest model reaching 375 hp. The series to which the tested model belongs is the A2R, which has four models: A800R, with 80 hp; A850R, 89 hp; A950R, with 99 hp, and A990R, with 105 hp. The A800R model is available to customers for purchase through the Mais Alimentos program. The A2R series has been offered to the market since 2019, with platform models, and since last November it was launched in the cab version and presented to the dealer network.

The A850R model succeeded in offering the A750 model tractor, which was very popular, especially among small and medium-sized producers. Although it is not the entry-level series, due to its engine power and being equipped with a cabin, it is a medium-sized, multi-tasking tractor aimed at medium-sized producers, from fruit growing, livestock farming, horticulture, among other activities that require a tractor of this comprehensive power range. After all, the Brazilian market offers a lot of these models that have power close to 100 hp.

Motor

The engine that powers this model is the 33CwC3, from the AGCO Power brand, with three cylinders, a displacement of 3.300cm3 and equipped with a turbocharger and intercooler. In the previous series that the A2R followed, the fuel injection system was mechanical and now the injection is electronic, controlled by a central unit positioned under the front hood, on top of the air filtration system. With this configuration, the maximum power obtained from the engine is 89 hp (65 kW) at 2.000 rpm according to the SAE J1995 standard. Maximum torque occurs at 1.500rpm and reaches 330Nm (33,6kgf.m).

With this innovation in the injection system, the user will benefit from a reduction in the level of emissions, more torque availability, provided by instantaneous adjustment of the quantity, and moment of injection, provided by sensors distributed in the engine, but also greater protection, as it If a fault occurs, the tractor will enter safety mode before further damage occurs.  

When opening the tilting hood, which, by the way, has a great opening angle, you will notice five radiators. The first, from the engine's water cooling system; the second, from the intercooler; the third, the air conditioner; the fourth, for fuel, and the fifth, for hydraulic system oil. 

Transmission

The transmission system of this model can serve four customer options. Firstly, the transmission of the standard version is synchronized with eight forward and four reverse speeds, the second alternative is a box with 12 forward and eight reverse speeds that uses a speed multiplier, the third adds a “creeper” super-reducer. and provides 16 forward and eight reverse gears, and as a more advanced version, the one that has a synchronized mechanical reverser, giving 12 forward and 12 reverse speeds. As the transmission version present in the model we tested was equipped with a “creeper” super-reducer with 16 forward gears and eight reverse gears, it was possible to find five gears in the range of 6km/h to 10km/h, more recommended for field work. and soil preparation. 

For us, who know the traditional principle used by Valtra of using the same transmission oil for the hydraulic drive, it was a positive surprise to learn that the EP SAE 90 transmission oil is exclusive to Valtra and that the ISO VG oil is used in the hydraulic system. 68, specific for hydraulic systems. It is also interesting to mention that the hydraulic pumps are external, located on the right side of the engine, which avoids the need to disassemble the tractor to maintain this system. 

The power take-off (TDP) has a standard rotation of 540rpm, but as alternatives the customer can request that the tractor comes with the 540/540E or 540/1.000 option. In a tractor of this size and power range, the economical 540 option is very important, as in light work, such as spraying, this will be the most recommended.

The three-point hydraulic system uses two robust external pistons and provides a lifting capacity of 2.600kgf. The activation is done using a single lever. The implement's descent speed is controlled using a lever located behind the operator's seat. The drawbar is an oscillating type, with coupling height adjustment.

The remote control system is independent and uses a gear pump, generating a maximum flow of 40 liters per minute with constant flow. The maximum system pressure is 180kgf/cm2. All models in the series can be equipped with one to three valves, depending on the customer's needs.

Organization

The basic design of this tractor is Finnish, with some features that differ from others. When starting to visually appreciate the tractor, you will notice that the front support is a single piece that at the front serves as a support for the front weights and extends as a support for the front axle until it joins the front part of the engine. This entire piece weighs 230kg and to it, to ballast the front part, four more pieces weighing 37,5kg each can be added. 

The ZF-branded front drive axle is centrally positioned, but maintains good clearance. The fuel tank is structural, involving the cardan shaft that drives the auxiliary front traction and can receive a volume of up to 79 liters of diesel oil, which can be expanded up to 104 liters with an auxiliary tank. 

Ergonomics and operating station

Regarding the operating position of this cabin version, some considerations may be interesting for analyzing the project. Access to the cabin entrance door is via a three-step ladder, with a non-slip corrugated metal surface. 

The only entrance door is on the left side and on the right side the glass is glued onto the cabin structure. The emergency exit is through the rear window. 

Once seated in the operator's seat, the controls are well positioned, whether through pedals, levers or switches. At the front, a panel with a tachometer, thermometer, fuel gauge and a digital panel with information on engine speed and instantaneous fuel consumption, an hour meter and, when the PTO is activated, an indication of its angular speed. The position of the manual accelerator is a little strange, with a large lever positioned on the side of the panel, moving up for acceleration and down for idling. 

The position of the steering wheel column is adjusted using a pedal located between the clutch and dual brake pedals. On the right side of all these pedals is the accelerator foot control of the engine speed.

The control and gear selection system is based on two levers placed to the right of the operator's seat, one for speed, where we have the L, H and R positions, corresponding to the low, high and reverse gear system, respectively, and the gear lever with four positions, corresponding to 1, 2, 3 and 4. Also on the right side are the two remote control system levers, the single three-point hydraulic system control lever, the PTO actuating lever and the to choose the rotational regime, which in this case selected the normal PTO mode of 540rpm and economical mode, 540 E. On the operator's left side is the parking brake and creeper super-reducer lever. It is interesting that to form the system of a 16-speed transmission over a 12-speed transmission, the creeper only acts on the low group, L.

All control of air conditioning direction and selection of its operation is placed on the roof of the cabin. In front of the operator there are three air directions and on the right side of the roof there are operating controls. 

At the rear, a window with good opening also serves as an emergency exit. On its frame there is a cable and harness entry of up to three inches, for logical communication with coupled equipment. 

Special care must be taken on the cabin floor, protected by a rubber mat with skirting boards that prevent it from lifting, protecting against the entry of dirt. 

On the right side, on the outside, the project included the placement of a plastic battery protection box and a small tool box. 

As protective measures for the operator, the manufacturer offers, among other devices, a shield-type PTO protector as standard. To put the tractor into operation there are two devices for safety and inadvertent activation, making it necessary to place at least one of the gear levers in neutral and press the clutch, which is a characteristic of the brand.

Several hours of testing

The test we carried out with the Valtra tractor, model A850R, was carried out in traditional ways, with a lot of field work and the opportunity to test the most different situations. There was plenty of time and area available and an implement well suited to the tractor. We used a Piccin V-harrow, model GAPCR, with two sections of eight discs each, with approximately 2.200mm of usable working width.

During the test we were assisted and accompanied by Flávio Pinotti Pastori, who is the Product Marketing Coordinator, Tractors & Front Implements at Valtra, who firstly explained to us a very important functionality available in this model, which is the possibility of establishing a memory of rotation. During work, the user can set a target rotation that they wish to use, for the journey or for maneuvers. If you choose to use it on the way, as is more common, you can return to the predetermined rotation just by touching a switch. To set the speed, simply accelerate the tractor to the desired speed and click the switch for three seconds and the memory will activate. During work, the user will realize the usefulness of this device, as they do not need to search for the desired rotation using the foot or hand accelerator. However, if during use the operator wishes to use the accelerator, it will remain available.

During the test we made consecutive passes on a rough terrain made up of mixed vegetation, with a predominance of brachiaria-type grasses, alternating marches and rotations. We used a speed of 7,2km/h as a base, in 3rd gear reduced to 2.000rpm, where we saw instantaneous consumption of 8,5 to nine liters per hour, but we also carried out part of the test using 4th gear reduced and also 1st high system gear. We concluded that in terms of comfort, fuel consumption, level of wheel slip and overall stability, the 3rd gear of the low gear system performed best.

We were able to work a good part of the morning and afternoon evaluating various aspects of the tractor that we were interested in testing. Regarding the operator's position, although the seat had mechanical cushioning, it was possible to notice a good position adjustment and proximity to the steering wheel, in order to provide a lot of comfort. The climatic conditions inside the cabin were quite good, thanks to the excellent air conditioning and the adequate position of the air vents. As for visibility, the width of the front glass and the good position of the columns were noted to improve visibility and monitor possible obstacles on the ground. The small diameter, three-spoke steering wheel makes the instrument panel easy to see. Even though it is a small to medium-sized tractor, the project includes several places for personal objects, which are so useful for our current habits of using mobile phones, glasses, etc. Inside the cabin, noise is greatly minimized, even in heavy operation such as harrowing on firm ground. 

As for the engine, which we already knew from other tests, we confirmed its ability to transmit torque and maintain the chosen speed. Since the engine now has electronic injection, the lack of smoke previously seen in engines with mechanical injection is notable. This is one of the gains obtained by this new technology. 

Test in the countryside and in the middle of the big city

The test site was the Central Experimental Center (CEC) of the Agronomic Institute of Campinas, known as Fazenda Santa Elisa. It is a farm of almost 700 hectares, very close to the city center of Campinas, where the research, development and innovation activities of the traditional Agronomic Institute are carried out, which, in turn, maintains a partnership with the tractor manufacturer.

Due to the pandemic, face-to-face work is currently very limited on site, however, there is an immense structure made up of many buildings used in scientific and technological research, mainly in strategic areas of agricultural production in the state of São Paulo, such as coffee growing, horticulture, grains and fibers.

More than a simple research site, Fazenda Santa Elisa is a huge environmental reserve, with large trees and a huge variety of vegetation. We couldn't have a better opportunity to spend a day testing agricultural mechanization.