New rear-mounted DISCO mower impresses

With an impressive 4.2 m operating width, the new CLAAS DISCO 4400 becomes the largest rear-mounted linkage side mower yet released by world’s leading forage harvesting manufacturer.

CLAAS Harvest Centre General Manager – Product, Tim Needham, says the new model incorporates the award-winning MAX CUT mower bed, central pivoting, floating suspension and a compact vertical transport position. “MAX CUT has set the standard for chop quality, ultra-smooth running and fuel efficiency since its introduction in 2014,” he says. “Its innovative design enables the large drive sprockets of the mowing discs to be placed well forward, ensuring maximum possible overlap and surface area with multiple teeth engaging at two points. Uniform spacing between the discs ensures a consistent cut."

“The wave-shaped mower bed is forged from a single piece of 5 mm thick steel profile, which in conjunction with the skids creates a dirt-repellent tunnel effect. The specially hardened inserts are shaped differently to accommodate the mowing discs as they run together and apart. This design provides a shear bar for an effective cut and maximum overlap for optimum crop flow without clumping.”

Like all CLAAS DISCO mowers, the PTO speed can be reduced to 850 rpm to reduce fuel consumption in lighter crops without compromising cutting performance. The permanently-lubricated mower bed is fitted with the SAFETY LINK safety module as standard. “Each cutting disc is protected by a predetermined breaking point, isolating it from the drive train in the event of contact with a foreign body,” Tim says. “An axial bolt holds the cutting disc firmly in place to prevent it flying off.”

The blades and covers of the counter-clockwise rotating discs are now painted red to avoid confusion during blade changes, which is standard equipment for all DISCO mowers in 2022. A removable blade box with separate compartments for new and used blades is now fitted as standard.

The optional double-swath laying is especially useful on wet or soft ground as it avoids driving on the forage. The mower bed is pivot-mounted at its centre of gravity for optimum ground-contour following. An adjustable spiral spring ensures that the mower bed comes down evenly during lowering, while two vibration dampers stabilise it as it is raised. Two pivot points on the arm at right angles to the direction of travel ensures optimal ground-contour following on uneven ground or when mowing banks.

DISCO 4400 incorporates the tried-and-tested ACTIVE FLOAT adjustable suspension system and CLAAS’ unique hydraulic collision protection. “ACTIVE FLOAT allows the ground contact pressure of the mower bed to be adjusted from the cab by spool valve while on the move,” Tim says. “In the event of a collision, the mower bar swings back and over the obstacle thanks to a rotating pin inclined at an angle of 15 degrees. Oil from the collision protection system is forced into the suspension ram to further depressurise the mower bed, protecting the mower from serious damage. Once past the obstacle, the mower bed automatically swings back to its working position.”

A unique vector folding system allows the mower to fold vertically to 120 degrees, effectively reducing the transport height to 4 m. “In its transport position, the mower is positioned diagonally behind the tractor and is supported by the headstock, thereby shifting the centre of gravity to the tractor’s longitudinal axle,” Tim says. “This solution significantly reduces the load on the front axle, which in turn, has a positive impact on the tractor’s steering behaviour. It also reduces sway, making it easier to negotiate tight bends, narrow roads or gates, which can be troublesome for linkage mowers that fold behind the tractor.” The optional storage headstock enables the mower to be parked in its transport position.

The DISCO series spans more than 30 front-mounted, rear-mounted and trailed models with operating widths from 2.2 metres through to 10.7 m, which are all fitted with the same award-winning MAXCUT mower bed.