Exclusive Test Drive Dakar Seeder, from Horsch

After testing Horsch's three precision seeders, the Maestro Duo in Terenos, in Mato Grosso do Sul, the Maestro Evolution in Barreiras, in Bahia, and the Maestro Kompass at the Gralha Azul Experimental Farm, in the metropolitan region of Curitiba, we completed the portfolio of Horsch seeders with the Dakar 18NT model in Rio Grande do Sul. Unlike the Maestro line seeders, this machine is aimed at sowing small grains and high planting densities. It is worth noting that Horsch separates its seeding machines by the type of seeds they apply, for example, for small seeds such as winter crops (wheat, barley, etc.) and cover crops, the Dakar line of seeders was developed, and for summer crops, or large seeds, such as soybeans, corn and cotton, the Maestro line of seeders was developed.

Although manufactured in Brazil, the Dakar features some components from models offered in Germany. According to the manufacturer, through the tropicalization project, 90% of the machine started to be produced in the country with the exception of the electrical components (sensors and cables), furrow closing wheels and the seeder coupling system. Therefore, the entire structural part is of Brazilian origin. The main differences between the German and Brazilian projects are in the sowing line. In Brazil, the pantographic system is used, due to the amount of straw and crop residues present in agricultural areas, and the hydraulic system for individual line pressure, responsible for increasing adaptation to the terrain and controlling the depth of seed deposition.

We have already mentioned on previous occasions that Horsch introduced products in Germany to the point of changing the way we think about agriculture and, mainly, soil management in that country. With experience and innovation, Horsch increased conservation management practices, proposing machines that reduced soil movement and intensive tillage, traditional in European countries. Reduced handling equipment, such as the Joker RT, recently launched in Brazil, has brought a new face to agriculture, reducing operations and intensity, in addition to saving fuel and improving soil conditions. Therefore, comparing Horsch's portfolio in Germany with that of other traditional companies, it is possible to observe this conservationist profile. The history of the brand's creation has a strong North American influence and is based on agriculture without a plow.

In this context, the Dakar is a machine specially designed to bring precision to a practice where this principle was not normally applied. In general, the machines used to sow pastures, cover crops and winter crops are technologically inferior and, therefore, less accurate. These are machines that sow in high quantities and with a continuous flow of seeds, without applying the concepts of singularity and precision in the spacing between seeds. However, Dakar emerged to change this reality, bringing technology and developing a unique product in the Brazilian market.

The Dakar seeder is a large machine, sold in Brazil in two versions, the VF model which is offered in a width of 8 m (46 lines) and in a width of 10 m (60 lines), both with a spacing of 17 cm between lines. And the NT model, which is offered in working widths of 12, 15 and 18 meters, with 70, 88 and 106 sowing lines, respectively, spaced 17 cm apart. Therefore, to carry out this month's Cultivar Máquinas Magazine Test Drive, we tested the Dakar 18NT seeder consisting of 106 sowing lines, with row spacing of 17 cm, totaling 18 meters of working width.

Vehicle, wagon or tank

One of the main parts of the machine is the vehicle, also called a wagon or tank that includes a fertilizer reservoir, in which several important components are placed on a robust chassis and where the side planting bars are attached.

The vehicle was completely developed to facilitate coupling, support the tanks and contain all connections, dosers and fertilizer and seed conductors. It is considered a vehicle because, during movement, the side planting bars close on it, so that the dimensions of the machine in transport position allow it to move autonomously, without the need for special trucks for transportation.

The machine's coupling header to the tractor's drawbar is the same as that of other Horsch models. Made in Austria, it has a safety chain and a jack for support and adjustment of the coupling height. The hydraulic connection uses three remote control valves (VCR), one for each turbine, one dedicated to opening, closing and lifting the planting bars and free return. The electrical connection is made via a standardized socket, used in the extra power system, and responsible for powering the sensors.

The fertilizer and seed tanks are placed in series, further ahead is the fertilizer tank with a capacity of 4.500 kg, followed by the seed tank with a capacity of 4.000 kg, totaling 8.500 kg for the Dakar NT seeder models. Unlike the precision seeders in the Maestro line, which have a total capacity of 9.000 kg. Access to the deposits is through separate gates, equipped with protection bars against the entry of unwanted objects, which could cause damage to the dispensers. The tanks are watertight, to maintain pressure inside, since the fertilizer and seed are transported from them by means of a positive air current. In the lower part of the tanks are placed the dosing systems, the seed doser, with double rotor, driven by two hydraulic motors, and the fertilizer dosing system, also double, which uses the channeled rotor mechanism, allowing the disconnection of sections in both cases.

On the side of the warehouses there is a large platform for the movement of people during inspection and supply, with handholds and protective railings, accessed by a five-step ladder.

At the rear of the wagon there is a frame where the planting bars (fertilization and seeding) are attached and from which the four hoses responsible for distributing seeds and fertilizer depart to each side of the machine. In this frame there is the presence of two air accumulators, which serve to facilitate the floating of the planting bars and their adaptation to the terrain.

The wagon is supported by two wheels measuring 520/85 R42, on an adjustable structure that allows the gauge to be changed, reducing it by 3,10 m for transport and expanding it by 3,70 meters for work. Two sensors on each side measure the position of the gauge and inform the system so that, with the shaft closed, the opening of the planting bars and collision between components is prevented.

Planting bars for fertilizing and seeding

Planting bars are the structures where the furrow opening and fertilizer and seed deposition components are added. In this test we were able to see the particularities of this system and the differences between the systems used in Germany and those developed for the Brazilian market.

As the Dakar is a project derived from machines produced in Germany, but developed particularly for the Brazilian market, it presents marked differences. The first is that in Germany a pivoted line articulation system is used, which serves very well for prepared terrain and is quite regular in terms of microrelief. For the Brazilian market, where direct sowing is practiced, with maintenance of all straw and the natural roughness of the land, plus that resulting from the passage of other machines, a pantographic system was chosen, where the freedom of vertical oscillation of the line is bigger.

In addition to this pantographic system, the manufacturer included a difference in length between contiguous lines, an offset of 65 cm between lines, that is, one line is shorter than the other. Since this gap facilitates the movement of straw between the lines, preventing the machine from clogging.

As the planting bars are enormous in length, a system was designed to transfer weight from the wagon to the lines, using independent hydraulic pistons and other smaller ones placed in each line, responsible for pressing them against the ground and ensuring the regularity of the depth. of sowing. This vertical force (downforce) varies from a minimum of 82 kgf to a maximum of 282 kgf. Furthermore, to guarantee even better quality during the sowing process, the manufacturer differentiated the pressure applied to the line by the pistons, depending on the lever arm generated by the different line lengths.

Weight transfer takes place through hydraulic pistons, the larger ones apply 160 bar of pressure and are used to open the planting bar, while the smaller pistons, present in each planting bar (one per bar), apply pressure of 65 bar. and provide the maintenance of pressure along the bar, with fluctuation occurring due to the action of pressure accumulators. For the operator, the pressure on the bar appears individually, on the monitor, for each piston placed in the sowing line, in percentage form, that is, zero pressure is that applied by the weight of the line itself, and can be increased up to 100% with the limit pressure imposed by the hydraulic cylinders.

At the end of the bars, wheels were placed with a large contact and support area, measuring 550/60 – 22,5, and a structure for placing metal ballasts at the ends of the planting bars, which in the case of the machine we tested were in number of eight weighing 35 kg each.

When it is necessary to collect the bar, for transport and displacement, two pistons placed in the central frame of the wagon will lift the frame and two other hydraulic cylinders will collect the lines upwards and then forwards, towards the deposit, where there is a specific location for support.

Eight distribution towers are placed at the top of the planting bar, four for seeds and four for fertilizers, distributed in four towers on each side of the equipment.

Fertilization system

The fertilizer application system is made up of two central dosers placed at the bottom of the tank, from where the product is carried by means of an air current generated by the turbines to the distribution towers, which, through dividers and smaller hoses, will conduct the fertilizer application system. fertilizer up to the seeding lines.

In the sowing line, a double disc furrower, of different sizes, opens the furrow and deposits the fertilizer between them, while two side wheels close the furrow. There is a gap of 30 cm between the furrowers and the closing wheels. In double disc systems, both in fertilization and seeding, the discs are 15 and 16 inches in size.

Sowing system

As with fertilizer, the seeds are also carried by an air current from the turbines and the towers are only responsible for dividing and distributing the product mass between the sowing lines. However, the amount of air applied can be changed, to control the product flow, through diffusers that limit and direct the air flow. There are two turbines, one for fertilizer and the other for seeds, which generate an air flow, taking the products from inside the deposits to the loading of the distribution towers, with rotations that vary depending on the dose and input used.

During the test we were able to observe the movement of straw between the lines, facilitated by the 65 cm offset between them. Furthermore, we verified that the pantographic articulation system and the pressure exerted by the cylinders allow the monitoring of the terrain and, therefore, a better regularity in the uniformity of seed deposition, both in quantity and in depth.

Two depth control wheels were placed on the sides of the two discs, one on each side, providing precise adjustment of the planting depth, which is done by inserting a pin into the holes. Each combined pin and hole position represents a 1 cm change in depth. Therefore, during the Test Drive, we measured the deposition depth of around 4 to 5 cm.

It is worth noting that each of the 106 lines is identified with a number, which is repeated on the tower diffuser, to facilitate the operator's easy intervention when, on the monitor, there is information about interruption/obstruction of flow in the line. All lines have their presence sensor, which informs the system of obstruction problems or lack of product (seeds or fertilizer).

Technology and embedded electronics

The machine is equipped with a management system called I-Manager, which controls seeding, using the open Isobus standard and Horsch Connect, which enables telemetry of the operation with remote monitoring of the work performed. For those customers who already have an Isobus monitor, Horsch allows them to use their own system, enabling them to receive signals from the machine's sensors. In the case of Sementes Aurora, where we carried out the test, the Fendt brand tractor had its own system and used Fendt monitors to control functions of both the tractor and the Dakar seeder.

Horsch Connect is a telemetry system, with internet connectivity that reproduces a visualization screen of the field work, of the location where it is used and with internet access in bands available on site, without the need for a corresponding cell phone operator. In addition to presenting information from the sensors of each line (seed and fertilizer). Horsch also offers customers its own Isobus standard monitor called the Touch 800 Monitor.

Monitoring the work inside the cabin, it was possible to observe all the operating parameters of the tractor and the machine, indicating that the operation was being carried out at 9 km/h, with an approximate turbine rotation of 3.500 rpm, in addition to the instantaneous fertilizer flow rates ( 200 kg/ha) and seeds (135 kg/ha). A vertical bar graph indicated the percentage of force applied to the planting lines.

However, the most impressive and useful thing, in our opinion, is the application provided by the manufacturer that allows you to activate the doser and simulate an adjustment to calibrate the equipment. In addition to remote viewing, the application allows control/management of the machine from outside the operator's station, making it possible, with this feature, to activate the dosers and simulate the adjustment.

To accompany this magnificent machine, we were accompanied in the field by a Fendt tractor, model 942 Vario, purchased by the client to make up this high-tech mechanized set.

Final considerations

It was a very positive experience to be able to follow and learn about this machine in the field, during the small grain sowing operation, with a precision similar to that used in sowing larger grains.

However, we need to be aware of the use of new technologies in modern machines, especially those that use hybrid forms of power, as the magnitude of hydraulic power consumption must be considered when sizing the tractor that will pull and drive the machine. In the past, only the mechanical power available at the drawbar was considered and currently, in modern machines, the hydraulic power and even the electrical power consumed must be considered, if applicable.

We were very impressed with the customer's opinion, expressed by the planting manager, Mr. Evandro Tramontini, who, when asked about his consideration of the machine's work, was emphatic in informing that the main qualities, in his opinion, were the excellent standard of sowing and the regularity in the quantity of seeds applied, in addition to the uniformity of the depth of seed and fertilizer deposition. For them, who work with seed production, this is a requirement when choosing machines.

He also emphasized the articulation capacity of the lines, which copy the terrain well, even with the amount of straw present in the area during the test. Therefore, his opinion is very important, as he presents experiences with machines from other brands on the farm.

Finally, we highlight the industrial quality of the product, which qualifies it as Premium in joining, welding and finishing elements. We had already been impressed by this detail in Horsch machines and increased our satisfaction as it was a product manufactured and assembled in the new factory in Curitiba (PR), with national engineering and labor standards.

Test location

The Horsch Dakar test drive was carried out at Fazenda Remanso, owned by the company Sementes Aurora. Although the company's headquarters and some areas are located in the city of Cruz Alta (RS), the farm where we were is located in the municipality of Tupanciretã. We followed the completion of wheat sowing, a key operation in the production of quality seeds that was being carried out at a speed of 9 km/h, with a rate of 135 kg of seeds and 200 kg of fertilizer per hectare. The area was covered with turnips as a cover crop.

In Cruz Alta, the store of the exclusive dealer Horsch Duaggro is being opened, which is the brand's first store in the state of Rio Grande Sul. There is great commercial expectation, as the store is huge and serves customers demanding quality machines.

They supported us during the test Adriano Placotnik, who is an agricultural machinery operator at Sementes Aurora, and Evandro Tramontini, who is the company's planting manager. Furthermore, they told us that with this set it is possible to carry out the wheat sowing operation with a quality that exceeds expectations and is much higher than that performed by machines from another brand that the property uses.

Also with us were representatives from Horsch, Alan Pitol – after-sales consultant, Fernando Pockrandt, who is a trainee in the company's marketing, Lucas Bastos, from factory engineering, acting as validation coordinator, and the products and management specialist ground driver, Edir Nisczak, who was with us in other tests of the brand.

Jose Fernando Schlosser,
Daniela Herzog,
Daniel Ciro de Sousa,
Agrotechnology Laboratory
Nema – UFSM