15 September 2000

Monsters hungry for action

The National Forage Maize

Day held at Shinfield, Berks,

last week provided its visitors

with a selection of maize

hungry self -propelled forage

harvesters. Peter Hill reports

STAND by your clamps… Contractors will begin clearing grass and maize silage fields with 600hp monster forage munchers next year as Claas forges ahead in the self-propelled harvester power race.

Unveiled at the National Forage Maize Day, the Claas Jaguar 900 boasts 25% more power than the current range leader, the 481hp Jaguar 880. It also features a semi-automated hydrostatic transmission for easie driving, and a 6m (20ft) rotary cutter that feeds eight rows of maize into the hungry machine.

The Jaguar 900 comes in response to continuing demands from contractors for bigger outputs and increased operating efficiency.

"Because of low milk prices, contractors are under more pressure than ever not to put up charges, but they are also seeing their costs continuing to rise," says Trevor Tyrrell of Claas UK. "The only way to cope is to extract more capacity from the harvesting team to keep down the cost a tonne of forage clamped."

The 900 promises a near-30% boost in maize harvesting productivity, reckons Claas, from about 28ha a day (70 acres) with a Jaguar 880 equipped with a six-row header to 36ha a day (90 acres) from the 900 and its standard eight-row rotary attachment.

"In grass, we would reckon on an average output of 60ha (150 acres) a day for first-cut silage from the 880, but 80ha (200 acres) from the bigger machine," adds Mr Tyrrell. "With a pre-production example, one contractor this year cleared 96ha (237 acres) in a 13 hour day, putting more than 4000t of grass into the clamp."

At this rate of intake, contractors will be looking to put two loaders on clamps – one to roll, one to shovel forage in as quickly as possible. But the 900s capacity also raises the prospect of replacing two forage harvesting teams with just one.

"That would enable contractors to still work large acreages, but would significantly reduce the amount of support needed in terms of tractors, trailers, loaders and drivers," says Mr Tyrrell. "It would also make the job easier to manage."

Though following the same format as its predecessors, the Jaguar 900 is a little longer in the chassis, but no less manoeuvrable thanks to a tighter-turning rear axle. A Mercedes-Benz twin-turbo intercooled diesel V8 engine, developing 605hp at 1800rpm, sits transversely in the tail with power bands transmitting drive to the chopping cylinder, blower, feed rolls and attachment.

The hydrostatic ground drive is more sophisticated in that it has a variable output motor as well as a variable output pump. In place of the 880s three-speed gearbox is a two-speed unit, but the new design provides more operating speed versatility.

An electronic control system automatically adjusts the hydraulic drive motors output to counter increased load from soft ground or hills. So the system effectively provides two speed settings in each gear to keep things on the move.

"Previously, the operator adjusted the system under manual control but at times this would have involved stopping to change gear," says Mr Tyrrell. "With the new design, that should not be necessary."

Other changes include feed rolls now reversed by hydraulic power to spit out forage plugs less aggressively; easier adjustment of maize header auger speed to match feed roller speeds; and longer chop length settings for maize.

All drives and other components are uprated to cope with the power hike, as is the cooling system. The rotating screen is replaced by a fixed cone-shaped screen with increased airflow; a vacuum sweep keeps it clean. Radiators and coolers are stacked vertically instead of in ranks to also maximise airflow. &#42

Claas put the Jaguar 900 self-propelled forager through its paces at the National Forage Maize Day. With a 605hp Mercedes-Benz diesel V8 and eight-row rotary maize attachment, it should be capable of felling 36ha/day (90 acres).