A full set of butterfly mowers, with conditioners and groupers, not only places a huge strain on the rear of a tractor but can also cause stability problems when folded. The latest Kuhn mower, known as the FC 9330 RA, addresses this problem.

The two rear units of the new set have a cutting width of 3.5metres while the front mower is 3.1m wide. This creates an overall cutting width of 9.3m with an overlap of 42cm to reduce the likelihood of uncut strips being left when turning or working across slopes.

The grouped swath width can be adjusted between 1.8m and 3.6m, or the groupers can be lifted out of work altogether. 

The company has aimed to reduce the total weight through redesigning the grouper units, making them more compact and using aluminium as the main constructional material for the frames carrying the belts.

This is said to offer a "significant weight saving" over previous models due to fully integrating the groupers into the machine design.

Twin hydraulic pumps for Kuhn mower

The grouper belts are driven by two separate pumps with the oil reservoir located within the frame. This arrangement allows them to be operated independently of each other.  

An inclinometer installed within Kuhn's ISOBUS compatible control systems can automatically adjust the belt speeds when crossing slopes to ensure consistent swath formation.

All the other operational functions (folding, lifting/lowering at the headlands, suspension) are driven by a valve unit connected to the tractor's own hydraulics.

The company claims that by dividing up the tasks in this way, hydraulic requirements during work are reduced, eliminating overheating and increasing the responsiveness of all the functions involved.

Full operation of the machine can be controlled by any ISOBUS terminal or Kuhn's own control units. The most frequent actions can also be performed through the company's own joystick option.