Comparison of class VII and VIII harvesters

Focusing on medium and large properties, the John Deere S 770, Case IH 7150, Valtra BC 7800, Massey Ferguson 9795 and New Holland CR Evo 7.80 harvesters, compared by Cultivar Máquinas, have technologies and systems capable of satisfying the most demanding producers.

In Brazil, grain production areas are expanding rapidly, requiring larger harvesters in order to obtain greater operational capacity. However, this requires correct planning, sizing and selection, aiming to optimize the harvesting operation on rural properties. In general, the choice of a grain harvester depends on many factors, for example, type of crop, size of the area and time available for harvesting. To this end, agricultural machinery manufacturers provide harvesters of different models and power classes, aiming to meet the varied demands depending on the needs of each producer.

In this sense, we bring to the readers of this edition of Revista Cultivar Máquinas a technical comparison of grain harvesters intended for medium and large properties, bringing together machines from classes VII and VIII from five national manufacturers: John Deere, Case IH, Massey Ferguson, Valtra and New Holland. The John Deere S 770, Case IH 7150, Valtra BC 7800, Massey Ferguson 9795 and New Holland CR Evo 7.80 models were analyzed.

To choose which models would be included in the comparison, we chose to initially consider the nominal power of the engine, however the different models were distributed between classes VII and VIII, according to the classification criteria established by the National Association of Vehicle Manufacturers. Automotive (Anfavea). In this way, we consider the maximum engine power, declared by the manufacturer, grouping all machines in Class VIII. For this, we apply a limit value of 5% considering the maximum power of the engine, corresponding to the difference between the machine with the lowest and the highest power. In this way, we classify only one model from each manufacturer based on proximity criteria, within a range in which they compete with each other in the market. 

The information contained in this comparison was obtained directly from technical materials available on the manufacturers' websites.

ENGINE AND TRANSMISSION SYSTEM

Grain harvesters have several systems, requiring energy to process a large volume of material, combined with their own displacement in the field, which leads to high power demands. 

The Case IH 7150 and New Holland CR Evo 7.80 harvesters are equipped with an FPT engine, model FPT Cursor 9. The Valtra BC 7800 and MF 9795 models share the same AGCO Power engine, model 9.8AT3. John Deere uses a John Deere engine, Power Tech Plus model, in the S 770 model.

The value for nominal power of the engines that equip the Valtra BC 7800 and MF 9795 harvesters is 415 hp, at a speed of 2.100 rpm. The John Deere S 770 harvester has 378hp at 2.200rpm, while the Case IH 7150 and New Holland CR Evo 7.80 models also have a 378hp engine, but the speed is not stated. In this comparison, all harvester models have a power reserve that is activated when overload occurs due to the simultaneous activation of systems, such as, for example, unloading grains during harvest. This power reserve, popularly called Power Boost, provides maximum power of 431 hp for the John Deere S 770 harvester, 450 hp for the MF 9795 and Valtra BC 7800 models and 442 hp for the Case IH 7150 and New Holland CR Evo 7.80 harvesters. 

The John Deere engine of the S 770 harvester has six cylinders with 9.000cm3 of displaced volume, and the FPT engine also has six cylinders and 8.700cm3 of displaced volume, equipping the New Holland CR Evo 7.80 and Case IH 7150 harvesters. 9795 from Massey Ferguson and BC 7800 from Valtra have an AGCO Power 9.8AT3 seven-cylinder engine, with 9.800cm3.

When comparing the models by power produced in each cylinder, the best relationship is found in the John Deere Power Tech Plus engine, with 71,8 hp/cylinder, followed by the FPT engine, with 63 hp/cylinder, and the AGCO Power with 59,3 hp/cylinder. cylinder. When we consider volume displaced by the engine and nominal power, the FPT engine presents the best ratio (23cm3/hp), followed by AGCO Power (23,6cm3/hp), and John Deere (23,8cm3/hp). In any case, we observed little disparity in the data, indicating a similarity in projects and technological levels.

As for fuel injection, all models use an injection system with electronic management, meeting the provisions of the Air Pollution Control Program from Motor Vehicles – Proconve, MAR-1 (Agricultural and Road Machines – Phase 1). To reduce the level of pollutants emitted into the atmosphere, AGCO Power 9.8AT3 engines are equipped with the so-called SCR System (Selective Catalytic Reduction). For the same purpose, John Deere engines use another technology, the cEGR (Cooled Exhaust Gas Recirculation) system. The engines that equip the New Holland CR Evo 7.80 and Case IH 7150 harvesters, in addition to having an iEGR (Internal Exhaust Gas Recirculation) system, use SCR. To enable greater efficiency and lower fuel consumption, the FPT Cursor 9 engines have a turbine with mechanical Wastegate pressure control and variable geometry (eVGT). 

Aiming to reduce stops for cleaning the cooling system, the AGCO Power 9.8AT3 engines that equip the MF 9795 and Valtra BC 7800 harvesters have V-Cool and V-Flow technologies, allowing the reversal of air flow and the exhalation of accumulated particles in radiators.

Regarding the transmission system, all models included in this comparison are of the hydrostatic type, which allow for greater agility and practicality in speed variations. 

The Case IH 7150 harvester has four speeds and features electronic gear shifting. The New Holland CR Evo 7.80 harvester, in addition to having the basic functions of a hydrostatic system, has Intelli Cruise automatic speed control technology. 

The John Deere S 770 model has two speed ranges, with Power Shift operation, commercially called Pro Drive. During transport, the transmission also integrates with an engine speed control system, Eco Mode, making it possible to travel at lower engine speeds, providing greater fuel economy.
Regarding the MF 9795 and Valtra BC 7800 models, the transmission system has four gears and eight working speeds. The speeds are activated using a switch (Low/High), positioned on the armrest.

TRACKING, SEPARATION AND CLEANING 

The threshing system of the harvesters included in this comparison is of the axial type, that is, it has a longitudinal rotor that, in addition to threshing the crops, separates the grains from the straw, due to the difference in size and mass. The New Holland CR Evo 7.80 harvester features two rotors with an individual diameter of 0,431m, totaling a track and separation area of ​​2,3m². The other harvesters in this comparison feature a single rotor with a diameter of 0,80m in the Massey Ferguson 9795 and Valtra BC 7800 models, corresponding to 1,36m² and 2,2m² of threshing and separation area, respectively. The John Deere S 770 harvester has a rotor with a diameter of 0,762m, with 1,1m² of track and 1,54m2 of separation. The Case IH 7150 harvester features a rotor with a diameter of 0,762m, a track area of ​​1,1m2 and 1,7m2 of separation.

The rotor rotation must vary throughout the harvesting operation, so that the adjustment favors threshing and separation, without causing damage to the grains and crop losses. Meeting this requirement, in the harvesters evaluated, the rotation can vary from 264rpm to 1.235rpm for the MF 9795 and the Valtra BC 7800; 230rpm to 1.300rpm for the John Deere S 770 harvester, and 250rpm to 1.150rpm in the case of the Case IH 7150 harvester. The New Holland CR Evo 7.80 harvester does not inform the public of the rotation amplitude of the rotors. 

The harvester grain cleaning mechanism consists of a tray, fan, upper sieve and lower sieve. The purpose of the tray is to stratify the threshed and separated material, allowing the lighter material to be left on the surface and the denser material at the bottom, so that, when projected onto the sieves, it can be better separated by density due to the action of the wind. The upper and lower sieves separate the grains from smaller materials, so that the grains can be sent to the reservoir, and what has not yet been threshed is sent to the tailings. 

Therefore, in addition to the technologies present in each system, the sieve area is important information, as it allows you to define the system's ability to clean the grains, whether in quality or volume. Of the models evaluated, the MF 9795 and BC 7800 harvesters have the largest sieve area, measuring 6,1m². The smallest area observed was in the John Deere S 770 harvester, with 5,1m2, with the other harvesters having intermediate values, of 5,5m2 and 5,4m2, for the Case 7150 and New Holland CR Evo 7.80 harvesters, respectively. 

All harvesters feature technologies in the cleaning system to improve quality and processed volume. In this sense, the automatic adjustment of wind speed in the cleaning system in relation to the longitudinal unevenness of the harvester stands out, that is, on slopes the fan speed reduces and on slopes it increases to compensate for the harvester's inclination and avoid losses. 

On the S 770 harvester the system is called Dyna-Flo and on the CR Evo 7.80, Opti-Fan. The other harvesters in this comparison do not specify the presence of this technology. The automatic feeding control system (Harvest Smart) of the John Deere S 770 harvester controls harvesting speed depending on grain loss levels, engine load and threshing pressure on the rotor. This harvester uses the Combine Advisor system, which continuously monitors the quantity of broken grains and impurities in the elevators and makes adjustments according to configurable limit values. New Holland's CR Evo 7.80 harvester has an additional feature (Intelli Cruise) which consists of an automatic system for adjusting the harvester's forward speed, so as to always operate at maximum engine capacity. This system can also be configured to automatically limit the machine's forward speed when estimated losses reach predefined values.

Another feature that increases the efficiency of the cleaning system and reduces losses on slopes is the self-leveling system, which has the function of compensating for the side inclination of the harvester, keeping the cleaning system horizontally level. Among the harvesters in this comparison, only the CR Evo 7.80 presents this system in its technical specifications. 

CAPACITIES AND DIMENSIONS 

When analyzing the models in comparison, considering the dimensional characteristics, we highlight that Valtra's MF 9795 and BC 7800 harvesters have the largest grain tanks, with a capacity of 12.334 liters, with a discharge tube flow of 150 liters per second. The John Deere S 770 harvester has a grain tank with a capacity of 11.600 liters and a discharge flow of 135 liters per second, with the lowest capacities being observed in the New Holland CR Evo 7.80 and Case IH 7150 models, with 10.700 and 10.600 liters, with flow rates of 126 and 114 liters per second, respectively. 

The length of the discharge pipe is also an important requirement as it facilitates unloading. The Case IH 7150, John Deere S 770 and New Holland CR Evo 7.80 models have lengths of 8,30, 7,90 and 7,30 meters, respectively, and the MF 9795 and Valtra BC 7800 harvesters feature a discharge tube with 7,40 .XNUMX meters long.

Considering the mass of the harvesters, Valtra's MF 9795 and BC 7800 models have the highest masses, 20.210kg and 20.090kg, and with intermediate masses, the John Deere S 770 and New Holland's CR Evo 7.80, with 18.970kg and 17.188kg. , respectively. The Case IH 7150 harvester had the lowest mass among the harvesters in this comparison, at 16.130kg. The difference in height between the models included was one meter, considering the shorter and taller models. The MF 9795 and Valtra BC 7800 models are 5,10 meters high, while the Case IH 7150 and CR Evo 7.80 harvesters measure five and 4,10 meters, respectively. The John Deere S 770 model does not have height information in its technical specifications.

Only the John Deere S 770, MF 9795 and New Holland CR Evo 7.80 harvesters presented length values ​​in their technical specifications, corresponding sequentially to 10,40, 13,24 and 8,4 meters. Considering working autonomy, the Case IH 7150 and John Deere S 770 model harvesters feature fuel tanks with a capacity of 950 liters. The tanks of the MF 9795 and Valtra BC 7800 harvesters hold 870 liters, with the smallest fuel tank capacity being that of the New Holland CR Evo 7.80, with 750 liters.

TECHNOLOGY AND PRECISION AGRICULTURE 

Innovative technologies, combined with precision agriculture tools, make grain harvesters true offices on wheels. The resources made available under this name contribute to reducing operator fatigue, facilitating harvest adjustments, reducing lost time, increasing machine productivity, in addition to allowing knowledge and productivity management at each point in a field. In addition to this, we have harvester models that perform automatic configuration per crop, eliminating any manual adjustments in adjustments and calibrations during harvesting.

The Case IH 7150 features the AFS system (Advanced Farming System), an optional package with autopilot, productivity monitoring and mapping system. The Auto Guide system, based on GPS and combined with mechanical guidance, makes the harvester precisely follow the rows of plants to be harvested, and when associated with the RTK signal, provides accuracy of 2cm.

The John Deere S 770 harvester has a generation 4 screen, which offers navigation facilities similar to smartphones. The harvest monitoring system (humidity and productivity), associated with Harvest Doc and an SF6000 antenna and receiver, allows mapping productivity in harvested areas. The machine is equipped with Auto Trac autopilot, which guides the machine via satellite. In the case of corn harvesting, this is assisted by the row sensor (Row Sense), combining satellite positioning data with data from the row sensor. 

Equipped with the harvest monitoring package (humidity and productivity sensor and NH AG372 GPS antenna), the New Holland CR Evo 7.80 is prepared for precision agriculture. The equipment can be installed at the factory or later, according to the user's needs. A color display (Intelli View IV) with touch screen monitors all harvester functions and reports on machine performance. It offers an autopilot system, with signal options of increasing precision, from free signal to RTK. 

The MF 9795 and Valtra 7800 harvesters feature the Auto Guide 3000 guidance system, with decimeter (standard) or centimeter (optional) precision. This system allows machines to be driven along a planned line, always maintaining full use of their cutting width. When the Omnistar correction signal is not enabled, Auto Guide works as a submetric using the internal Trupass algorithm. For these two models, the optional FieldStar II Precision Agriculture system provides instant measurements of grain moisture and crop productivity through impact sensors. The Farm Solutions system processes data at different points in the field, reporting productivity in kg/ha of dry grains. An optional telemetry system (AgCommand Advanced) provides the transmission of data obtained by the harvester in real time.

CUTTING PLATFORM

For grain crops, mainly soybeans, the five machines compared have a platform specification between 35 and 40 feet in cutting width. Manufacturers also provide recommendations for irrigated rice, using rigid platforms, and special platforms for corn. 

John Deere recommends the Hydra Flex Draper 770F platform for grain harvesting for the S600 model, with a flexible cutting bar and flotation resulting from the use of hydraulic cylinders. The manufacturer reports that the fluctuation reaches approximately 15cm. For rice, the recommended platform is the Hydra Flex Draper 600R model, which is manufactured with wear-resistant components. 

For corn cultivation, the recommended platform for this machine is the Hydra Flex Draper 600C, which is characterized by ease of maintenance as it does not require tools to access the attack angle adjustment mechanisms. The manufacturer praises the improvement of the project in terms of reliability, as several items were worked on in this regard, such as worm width, adjustable scrapers, chassis strengthening, sealed transmission with oil-bathed lubrication, divider nozzle protection scrapers and rubber retention, with easy adjustment of the angle of the dividing nozzle and wider collection chains. This platform connects to the machine through just one point, which speeds up the coupling and disengaging process.

For the 7150 model harvester, the Case IH brand recommends the Draper platform, which can be rigid or flexible. The flexible platform, called 3020 Terraflex, is recommended for grains in general, with the Field Tracker® system providing flexibility to follow the microrelief of the surface. This platform has the advantages of having a larger auger diameter and retractable fingers throughout its entire length. For rice, the recommended platform is the 2010 model with rigid cutting bar. The manufacturer reinforces arguments that the knife boxes have greater durability and that the load capacity of the bearings has been increased, resulting in less maintenance and, therefore, fewer stops. New tracks were also placed on this machine in order to reduce wear, reducing maintenance costs. 

For grains in general, the Valtra BC 7800 uses the Draper 600FD platform, which also has a flexible cutting bar with the Schumacher cutting system, well known for its quality and features such as double fingers and knives and rollers mounted in inverted positions, one in relation to the other. Just like the John Deere platform, the Draper 600FD has a single-point hitch. The inclination of the bar in relation to the horizontal can vary by six degrees upwards and six degrees downwards. As an alternative, both brands offer a traditional spiral platform, which is the Hiflex 600F model, whose main feature is lower weight compared to the Draper version using a system provided by Schumacher, with cutting bar flexibility. 

Massey Ferguson informs that there are no indications for a rigid cutting bar platform for the MF 9795 model. The recommended flexible platform is the Draper Dynaflex 9300, MF 9255 and MF 9250. It uses the Schumacher cutting system, as well as the Valtra product , as the companies are from the same Group. Therefore, the slope of the cutting bar is the same, as is the single hitch point. The manufacturer highlights as the main virtues of its equipment the hydraulic adjustment of the knife angle and the pressure on the ground, the cardan transmission and the transport carriage for low speeds. 

It is a platform that is characterized by simplicity, as the cardan and mechanical drive for the other components eliminates electrical and hydraulic drives that can cause maintenance costs. Among the models offered by Massey Ferguson, the reel can be split or in a single piece, in the cases of the MF 9255 and 9250 platforms, respectively. The rubber mats are reinforced with fiberglass and the sides have a different width than the central one. A balance between width and speed prevents material return. 

For corn, the two manufacturers' alternative is the L, M and HiChopper version platform. One of the valued points in these models is that the project was developed to always separate the stem from the cob at the entrance. 

The platform recommended for New Holland's CR Evo 7.80 harvester is the flexible Draper, Super Flex version, for grains in general, and rigid for crops such as irrigated rice that are unavailable for the widths recommended for this class, but available in the width 30 feet of cutting. The manufacturer highlights the existence of torsion blocks, dividing the unit into small sections, for platform flexibility, as well as height and fluctuation control with electric drive. The information that air pockets are available to support the knife box is also interesting. There is a specific offer for bean cultivation. Furthermore, it is stated that the side conveyors are narrower than the central one, to prevent the return of harvested material. This manufacturer also reports having equipped the system with a low-speed transport device. 

The corn harvesting platforms recommended for this harvester model are of two classes, the Exitus, more economical, and the Premium, more developed and technological. The Premium platform can be purchased with spacings of 50cm and 80cm between lines, it features more technology in the project, such as aluminum side drive protection with lubrication, main transmission shaft bearing and pick-up chain with greater load capacity, deck adjustment of the disconnector actuating hydraulically from the operator's station and the individual clutch per line unit. 

FINAL CONSIDERATIONS 

When carrying out this comparison we noticed that some manufacturers do not offer enough information for the customer to better understand the product, which can be a decisive factor when choosing a particular model or brand of harvester. Furthermore, the information contained in the form of comparison is important and facilitates decision-making by farmers when purchasing a new harvester, adequately meeting the producer's needs. 

Therefore, choosing the ideal harvester model from those offered on the market by different manufacturers represents gains in efficiency and operational performance, considerably reducing operating costs.

Jose Fernando Schlosser, 
Walter Boller,
Junior Garlet Osmari and
Gabriel Almeida de Aguirre,
Agrotec - UFSM
Alexandre Russini,
Unipampa
Gilvan Moisés Bertollo,
UTFPR