John Deere 8500 Self-Propelled Forage Harvester

Efficient machine design

Capacity, harvesting quality, machine efficiency, and total cost of ownership have always been important differentiators for self-propelled forage harvesters (SPFH). Machine size, weight, or soil compaction associated with weight, and tire size is critical to producers' acceptance of certain machines on their fields. A key demand on the 8000 Series was to find a machine layout for optimum weight distribution and maximum capacity potential.

The driveline concept has been optimized for maximum flexibility in setting the individual component speeds and also synchronizing certain functions for maximum harvesting quality. Specific component design has been implemented to improve efficiency.

Components have been laid out for matching the power demand, not only of today’s producers, but also meeting potential requirements of future users.

Most advanced wear-resistance technology is applied on all crop-flow elements to assure full-season harvesting uptime. Longer component wear life significantly lowers the cost of ownership.

Holsteins eating forage grains

The unique Dura-Drum™ cutterhead design, together with the portfolio of cutterhead configurations, allows 8000 Series machine owners to perfectly specify their harvesters for meeting all operating demands. Three different cutterhead configurations with 10, 12, or 14 lines of knives, a full or half set of knives, and in conjunction with 1100 or 1200 cutterhead rpm provide an overall range of length of cut (LOC) from 3 mm (0.12 in.) up to 52 mm (2 in.). The 8000 Series Self-Propelled Forage Harvesters (SPFH) meet any customer requirements.

Kernel processor technology

John Deere Premium KP™

John Deere XStream KP™

Industry-leading crop processing technology, such as from a conventional roller kernel processor, or from the latest XStream KP disk processing technology characterizes the 8000 Series approach to highest harvesting quality, essential for maximum performance.

8000 Series SPFH can be equipped with crop reprocessing technology, resulting in corn silage samples complying with highest-quality standards and kernel processor scores. Crop processing principles are implemented on the harvesters reflecting the various crop conditions as well as the harvesting capacity of the machines relative to their engine power.

In the 8100 and 8200 models, the John Deere Premium KP is installed in base.

On machines in the higher performance classes (8300 – 8600), the choice between the John Deere Premium KP and the John Deere XStream KP allows for tailoring a machine exactly to the needs and requests of dairy or biogas producers. The metabolic speed of crops in meat production or ultra-high performing dairy cows or a biogas digester is essential, where the fermentation speed is the key to the economic success of the plant.

To address different crops and crop abrasiveness, different rolls can be selected. Furthermore, the speed differential can be altered, addressing the processing requirement relative to predominant crop maturity or moisture.

With the swing-in/swing-out concept, the kernel processor can be easily set to its working or storing position. The swing-in/swing-out is conveniently done in the machine service compartment. The processor swaps with a crop transition chute with just a few turns. In short-term alternating application, the processor can stay in its parking location. When it is not needed for a longer time, an optional articulating lifting beam with an electric hoist allows convenient removal from the machine.

Kernel processor swing out

Kernel processor swing in

Kernel processor

Chopping technology

Rotor flywheel design

8000 Series SPFHs feature the unique John Deere Dura-Drum™ design. The cutterhead's distinct flywheel design or the retracting knife segments protecting the rotor against destruction by foreign objects remain unchanged. Cutterhead speed is set at 1100 rpm at rated engine speed.

Although the main crop flow components have been relocated in the machine, key features like a short spiral cutterhead band and the reverse knife sharpening method assure the advantages of exceptionally low power demand for cutting and crop transition remain on the 8000 Series.

On the cutterhead, the regular spiral cutterhead band can be replaced with a recutter floor featuring a set of mower bar knife sickles sticking out into the crop flow. The chopped crop mat is screened while passing the floor, so that leaves or longer crop particles are re-cut for perfect chopping results under adverse conditions.

Such a recutter floor can also be provided as a bi-pack with the machine from the factory.

The operator can choose between two adjusting cycles:

1. After a grinding activity the procedure is interrupted to allow knife inspection, only the grinding icon on the display is lit.
2. Knife grinding and shear bar setting are performed successively without interruption, both grinding and shear bar icon on the display are lit.

Shear bar options are also offered.

Cutterhead

Cutterhead

Cutterhead

All 8000 Series machines are narrow body and come with a standard harvest channel. The feedroll channel measures 660 mm (26 in.). A drum equipped with knives is 12 mm (0.5 in.) wider on either side, assuring a uniform crop flow across the full width of the cutterhead. This prevents uneven wear on knives, which would cause poor shear bar setting and result in poor chop quality.

When rebuilding seasonally with new knives on 8000 Series, the cutterhead is a fixed dimension, and the cutterhead housing is then adapted to the drum size with shims under the housing wear liners. By doing so, it is assured that the cutterhead is perfectly seated in the housing, safely preventing crop particles from bypassing the drum alongside the side walls.

The cutterhead diameter has been set to 670 mm (26.4 in.), complete with knives to allow for 12-knife rows on the rotor’s circumference as well as addressing the crop unloading angle into the redesigned crop transition. The higher number of knives significantly improves the machine's harvesting capacity when chop length needs to be extremely short.

8000 SPFHs use heavy-duty knife equipment. Knives are 9 mm (0.4 in.) thick and feature extra-long 20-mm (0.8-in.) hard facing. The knives are longer, allowing a sufficient knife overhang; this allows using up the entire hard facing on the knives without the necessity of relocating them, and still retain efficient crop throwing to the kernel processor or crop accelerator.

The knife carrier profile has been improved so that there is no negative impact on the crop transition from an extended knife pocket unloading cycle. This configuration also avoids premature crop stream funneling in front of the critical kernel processor processing gap.

Cutterhead design and configuration options, including a Dura Line™ option where the individual knife carriers are hard faced, specifies a machine for its desired application.

Shear bar

Shear bar configuration

The traditional knife/shear bar configuration does not change at all. There are significant design and handling changes implemented on these machines, conceived to deliver a much higher performance.

The shear bar is fixed with three bolts on a massive cast-steel anvil. This anvil is mounted on bearing spring plates out of high tensile but yet flexible steel. This shear-bar anvil design allows asymmetric shear bar traveling to address potential one-sided cutterhead wearing through systematic off-center machine loading.

A second design change driver was on the natural shear-bar wearing cycle; the generic bending forces between knives and shear bar would be significantly elevated on machines with higher-capacity potential. The middle fixing prevents the shear-bar gap from increasing in the machine's center assuring perfect crop-cut quality throughout the entire life-cycle of the shear bar.

On the 8000 Series, remote electronic knife sharpening and shear-bar setting come standard. The machine automatically applies the right shear-bar setting method appropriate to the cutterhead maintenance situation.

An extended setting procedure is automatically applied when a new shear bar has been installed and set the first time, or whenever the operator has had the shear bar intentionally travel away from the cutterhead.

This is a more complex adjustment logic assuring a shear bar will be set absolutely parallel to the knife line, independent from the initial shear bar position.

After a normal periodic knife grinding, a shear bar quick-adjustment logic would move both sides of the bar simultaneously to final position.

Unique machine layout maximizes power efficiency

Maximized harvesting efficiency

Power-efficient crop handling and machine propulsion in the field are critical to maximum field performance on given engine power.

On the 8000 Series Self-Propelled Forage Harvester (SPFH), this is addressed through a unique machine layout leading to a fully harmonized crop path, avoiding any abrupt change of flow direction in the channel.

The 8000 Series machines feature automatic header detection, which automatically triggers all relevant calibrations and pre-settings memorized on the machine controllers.

Header lateral ground adaptation as well as a driveline synchronized with the machine crop feeder, or an optional dual header drive where the pickup tine reel would adapt the machine forward speed, and the feed auger speed would be in line with the feedroll speed, are leading to unobstructed crop entry into the harvester. Capacity and harvesting quality is maximized.

Advanced header control and active header guidance on corn heads allows precise header positioning through feelers, while the head is not in contact with the ground, resulting in an absolutely even stubble field.

Header attaching comfort is unmatched. Operations are reduced to manually applying the locking lever, and quick-coupling electric and hydraulic services.

Cooling package serviceability

Cooling package accessibility

The entire cooling package for the 8000 Series Self-Propelled Forage Harvester (SPFH) cooling system can be accessed from the service compartment in the middle of the machine. Everything can be reached easily in one spot on the machine, making daily servicing convenient. The constantly rotating radiator screen allows a wide opening angle for easier service. No tools are required for servicing the air filters. The filters can be reached when standing on the left side of machine in the service room.

Fuel tank

Fuel tank

The standard 1100-L (290.6-gal.) fuel tank and 43-L (10.6-gal.) urea tank are located in the low center and on the low center left-hand side of the machine. This guarantees a low center of gravity. Both tanks’ filler necks are accessible from the cab stairs. Refueling is done from one single position.

Cutterhead access

35 degree V-opening

Feedroll door opening

The 8000 Series cutterhead unit concept provides two methods to access the shear bar and cutterhead for inspection or maintenance.

Leaving the header mounted on the machine and releasing the top locking mechanism together with the top side pivot pin, while the lower clamps remain locked, allows access to the shear bar and the knives through a 35-degree V-opening.

Detaching the header and releasing the upper and the lower locking mechanisms, provides convenient access through a feedroll door opening action, similar to the 6000 and 7000 Series Harvesters.

34 percent larger footprint

Weight distributed evenly

ProDrive is the industry-leading ground-drive propulsion.

Due to weather conditions, the harvesting window becomes shorter and in some areas around the globe, the machine has to work under very wet and soft soil conditions. This leads customers to get a forage harvester which is able to manage harvesting in these varying conditions.

The 8000 Series with the ground-drive-propulsion ProDrive, in conjunction with largest tires in the industry and optimized weight distribution, leads to maximum performance and uptime in soft soil conditions.

The largest tires, with a diameter of 1067 mm (42 in.) and a width of 900 mm (35.4 in.), deliver in comparison to a 7000 Series tires, a 34 percent larger footprint helps the 8000 Series with increased traction as well as less ground compaction.

The 8000 Series performs without compromises due to the industry-leading ground clearance, especially in soft soil conditions.

ProStream Crop Flow

ProStream Crop Flow

A key concept for the 8000 Series Self-Propelled Forage Harvester (SPFH) line was to position all crop-flow components to avoid any restrictions, as well as to design the crop path for minimum kinetic friction on the particles.

The 8000 Series crop-flow channel begins at the harvesting unit pickup tines or crop-row pointer. On the actual harvester, it starts with the feedroll arrangement. John Deere has implemented a concept layout well proven on the 7000 Series.

Key characteristics are a set of front feedrolls where, when the header interface is in a vertical position; the upper-front feedroll (UFFR) reaches out about 60 mm (2.4 in) over the crop in front of the lower one, grabbing the mat from the harvesting header and pulling it into the feedroll gap. This is a key function when corn headers without feed augers are mounted; assuring the machine’s crop feeder is the sole length-of-cut (LOC) metering unit of the harvester.

On its way to the cutterhead, the radial-arc-feed roll arrangement applies pressure to the crop for superior cut quality. The crop mat is perfectly compressed until the last second before transitioning into the knives.

From the moment the knife pockets start unloading, the cutterhead band takes the crop particle stream, collecting it for launching into the crop chute.

The crop path follows a constant curve between the cutterhead floor and the accelerator entrance. The crop accelerator, the spout transition, and the spout build the machine’s crop discharge device. All components that have an acceleration impact on the crop perfectly integrate tangentially into this curve for a fully unobstructed crop flow.

With 1800 rpm, the accelerator provides sufficient thrust to the crop stream for loading with the largest of heads without consuming excessive power. Rather than being carried by the accelerator rotor, the crop follows the curve of the accelerator band before moving through the transition directly into the spout base, from where on it follows the spout contour.

The crop hits the transition front liner just below the spout entrance at a shallow angle, minimizing component wear and inertia losses. This constant flow curve was designed to the spout as gently as possible so that the crop flow components had the least friction effect on the crop particles.

Sufficient space on the vehicle for a cab that allows for more operator leg room, though keeping the overall machine compact, was a key demand.

Ultimately, the 8000 Series SPFHs provide superior crop-flow efficiency, resulting in industry-leading machine capacity in respective horsepower classes as well as low-specific-fuel consumption (amount of diesel per ton of crop harvested). Combined with Dura Line™ technology, the 8000 Series SPFH triggers the lowest possible machine maintenance with minimal cost of operation.

8000 Series crop discharge

Crop accelerator

Crop accelerator

On its way to the trailer, the crop has to be elevated more than 4 m (13 ft) high between the accelerator exit and the spout end. It has to overcome a certain friction along the transition and spout liners until it is ejected off the spout end cap. When opening corn fields, producers can expect crop being airborne over a distance of 15 m to 20 m (50 ft to 65 ft) into the following trailer.

It is the task of the crop accelerator to provide sufficient thrust with appropriate efficiency to the crop particles to be loaded in all circumstances. An exactly specified air inlet in the accelerator housing assures a perfect spout crop jet when the kernel processor is installed.

Crop transition

The crop transition is completely lined with high-grade wear elements, which can easily be inspected and replaced from the machines service compartment through an access hatch. A unique manufacturing process allows even, customized hardening of the wear liners, perfectly addressing the individual wear situation in the cone. The transition is bearing the massive head gear-driven spout turning mechanism.

8000 Series SPFH features a spring-loaded cam-torque limiter inside the spout-turning drive mechanism. The spout hitting an obstacle is perfectly secured. However, the spout would never rotate uncontrolled and hit the cab. The spout turning sensor precisely monitors the spout position even when the spout clutch would have been triggered and mechanical end stops additionally secure the system.

Spout with multiple length components

Spout

The spout on the 8000 Series features modular architecture. On the basic module, the wear liners are a structural part of the component. This module features a box design closed by the wear liner. A worn-through liner discovered too late would not lead to damage of the spout structure, but replacement would rebuild the spout like new.

The liner of the base module is segmented addressing the wear situation on individual sections. In the standard configuration, all four liners on the base module are made of Hardox® steel; however, for severe conditions, section one and two can be specified in Dura Line™ version.

When specified with HarvestLab™, section two would carry the near-infrared (NIR) sensor. In this case, the wear liner always comes in Dura Line™ version, and it would feature quick-attach clamps for easy maintenance of the HarvestLab sensor.

The HarvestLab installation is easy and is completed by directly bolting it to the wear-liner segment. The NIR sensor is once aligned with the carrier sheet, and whenever serviced, the entire assembly is then unlatched from the spout and then re-clamped.

Header mounting and ground contour following

Header mount

8000 Series front-end interface is a laterally tilting frame. Multiple factors led to John Deere’s common harvesting units interface plate and redesigned header mounting, including:

• The need for more front feedroll travel as well as a greater roll diameter addressing the increased harvesting capacity of the new line.
• The intention to integrate the lateral tilt device into the harvester vehicle, because the larger feedrolls of the machine would not allow for enough tilt with the combine interface.
• The ground adaptation can be passive, with a set of springs bringing back the frame into neutral level position or active (optional) with a hydraulic cylinder, positioning the header in reference to the signals from AHC sensors on the respective header.

This change eliminates multiple lateral-tilt devices on headers. An additional advantage is the header's self-centering feature of the attaching cones on the frame required to implement the automatic header drive-shaft coupler. Central header locking is a standard feature and comes with the hydraulic multi-coupler.

High-arc spout showing available extensions

There is a set of intermediate spout extensions of various lengths addressing the loading distance relative to SPFH header width. For weight reasons, the spout extensions are built from aluminum alloy with a thin steel liner inside. The spout end-cap module bolts to those intermediate sections.

The standard configuration shipped from the factory would be dedicated to grass harvesting with a windrow pickup or corn harvesting with a 6-m (20-ft) corn header. A second spout segment to extend the spout for 7.5-m (25-ft) header width can be by-packed with the harvester. For 12-row, 9-m (30-ft) corn harvest, a foldable spout segment is available.

Hardox is a trademark of SSAB Technology AB.

Crop intake

Crop intake rolls

Mechanical spring

Both Series of self-propelled forage harvesters (SPFH) use four feed rolls to ingest crop with the top rolls pulled down by four springs. Their tensioning can set manually. All four rolls are driven with an infinitely variable transmission and speed synchronized to ensure smooth and reliable feeding of the cutterhead.

Feedrolls

The front set of feedrolls in charge of taking the crop off the front-end harvesting unit have been redesigned to be more adaptive to the tremendous variability of harvesting conditions.

The upper-front feedroll (UFFR) is now solely a ridge-type design and standard fit with replaceable and reversible wear teeth. The ridges feature a triangle-teeth design and are part of the roll segments. Behind the ridges there are tapered composite teeth bars clamped on the segmented roll. The wear slats feature the same triangle-teeth design on one side and are smooth on the other side, which makes them ideal to adapt the roll to the full range of crop conditions from dry and smooth hay to wet and sticky alfalfa.

The lower-front feedroll (LFFR) features a similar design; however, replaceable teeth bars with identical serration are optional wear elements. Inside the lower front feedroll is a rectangular tube carrying the metal detector coils, helping the operator to enjoy full machine and crop protection.

IVLOC™

Infinitely variable length of cut IVLOC

The entire feeder assembly is driven from the main feedroll transmission on the right-hand side of the roller frame. Power is sourced from the hydrostatic motor. The static set of lower-front feedrollers is directly driven from the gearcase. The moving set of upper-front feedrollers have their proper transmission on the left-hand side supplied with power via a transversal U-joint shaft. The main concept driver is to allow wider crop channels inside a narrower machine fit with the biggest tires in the industry.

Machine foreign-object protection

A points to the stone detector and B points to the metal detector sensors

The well-known and proven electromagnetic metal-detection system with its multi-sectional sensor coil is standard on all John Deere SPFHs. When tripping, metal object location in the crop mat is indicated in the cab. Also, the metal detector would trigger the selective control valve (SCV) 1 on the SPFH to automatically raise the crop compressor device on the grass pickup. Re-engaging the feedrolls would then lower the device into place again.

As an option, the metal detector can be completed with an additional stone detection feature where a sensor is placed inside a rectangular tube within the lower front feedroll. This sensor is correlated with a second sensor located on the right-hand side of upper front feedroll arm. One sensor detects stones striking the lower roll, as the other detects rapid feedroll movement of the upper roll. Both sensors work together, and as a result the verification of a solid foreign object is significantly improved, minimizing stone detector false tripping.

When the sensor is tripped, the feedrolls stop both with the metal detector or stone detector and automatically raises the crop compressor device on the hay pickup. Re-engaging the feedrolls would then lower the device into place again.

Stone detection offers a competitive advantage in the marketplace as it detects not only large stones or rocks, but small ones as well using knock sensors. This system provides operators with peace of mind while chopping in rocky conditions to prevent damage to the SPFH. Detecting stones and preventing them from entering the crop path of the machine not only reduces damage to the machine but also lowers the cost of operation and increases uptime to the customer which leads to increased productivity and performance.

Header drive and control

The 8000 Series SPFHs supply crops to the chopping components.

Improvement is driven by automatic header detection, variable and efficient hydrostatic header and feeder drive concept, revised header ground contour following, sophisticated machine protection technology, and feedroll redesign.

Automatic header detection

8000 Series machines are equipped with the multicoupler interface for all hydraulic and electric services to the SPFH harvesting headers. Through the electric wiring coding in the multicoupler, distinct header identification is assured, allowing it to automatically refer to customized header settings stored in the respective controllers onboard the SPFH. This allows the operator to instantly call back all settings that resulted from the last harvesting experience. All calibrations required for proper header operation are automatically recalled in full when attaching the header.

Hydrostatic header drive

Hydrostatic motor

On the 8000 Series, the harvesting headers are driven by a hydrostatic service. The hydrostatic pump on the machine’s main power take-off (PTO) transmission supplies power to the motor behind the vehicle front axle. A U-joint shaft assembly transmits the torque to the header entry transmission.

An optional dual-header drive provides a power split to the feeding components such as on a grass windrow pickup. In this case, the hydrostatic service would drive the pickup auger and a second hydraulic service would separately power the pickup tine reel.

Variable oil-flow control allows easy synchronization of drive speeds with the velocity of respective components on the harvester. The entire header can be driving with a constant speed setting, or the header main drive can turn at a desired speed ratio synchronized with the harvester’s feedroll speed.

The dual drive allows individual synchronization of the header feed auger with the feedrolls and the header tine reel with the vehicle’s forward speed when harvesting.