LEMKEN Rubin 12 disc harrows: Machine spotlight

LEMKEN has been a leading force in the field of soil cultivation and one of its latest products, the Rubin 12 compact disc harrows, is testament to its manufacturing excellence and ongoing commitment to servicing the global farming community.

A recent demonstration day at the IREC field station in Whitton, NSW, saw a modified Rubin 12, sporting 29-inch discs and a heavy ridge roller on the back, run in moist conditions over cotton trash sown on one metre-wide rows in a bankless channel system.

The Rubin 12 was showcased alongside the Karat 9 tyne cultivator to a crowd of cotton growers from the Riverina region.

One of LEMKEN Australia's newest releases, the Diamant 16 mouldboard plough which has just recently touched down in Australia, will also be showcased to farmers in the near future.

To cater to local conditions, the distance between the front and rear gang of discs on the LEMKEN Rubin 12 had been extended by almost 50cm.

“That was done based on feedback from North America, Canada and Australia on trash flow in cotton and maize,” said LEMKEN Australia managing director, Robert Wensing.

“The big difference between these machines and others is the disc diameter and angle – every disc is at a 20 degree angle to the ground and 16 degree angle to the forward direction of the machine.

“So, it is a lot more aggressive than a normal speed or compact disc.”

The Rubin 12 was initially launched in Australia two years ago but has been heavily modified to better suit the tricky cotton conditions.

“The biggest advantage is the sheer size of the disc and the 20 degree angle to the soil so it tends to cut right underneath the root mass,” Wensing said.

“We look to work at 20cm deep right across the profile, aiming below the bottom of the furrows to tear every cotton plant out to make sure it won’t regrow."

The LEMKEN Rubin 12 features a symmetrical disc pattern so instead of the front row of discs flowing one way, and the rear discs flowing the opposite way, the machine has an equal split on the front and back.

“This means the machine tracks better behind the tractor and there is more efficient setting of the GPS autosteer – overlap setting can be reduced from 50cm to five to 10cm,” Wensing said.

“A lot of technology has gone into the design of the centre covering disc to be able to do that.

“It has a heavy overload protection device of 300-400kg of breakout force – one can let go if it has to without lifting the whole machine out of the ground, and it protects life of the bearing quite significantly.”

Wensing said trials had been undertaken in northern NSW with the machines working on different angles across the paddock.

“Here we have 100 per cent of the cotton dislodged and uprooted at a consistent 20cm of depth right across the profile,” he said.

“It is definitely flat enough to run an air seeder straight behind it with no other passes required."

He added the Rubin 12 works in hard, dry or heavy soil and is all about intensive cultivation in one pass.

The demo LEMKEN Rubin 12 disc harrows at Whitton was pulled by a Case IH Magnum 340.

The serrated concave discs have a diameter of 73cm and a thickness of 6mm, allowing for working depths of up to 20cm.

Each concave disc is individually attached to the frame with pre-tensioned spring elements to maintain working depths even in hard soils.

They are inclined 20 degrees to the soil and 16 degrees in the direction of travel to provide optimal mixing and crumbling results.

The discs are always true-track following and can independently deflect upwards if they hit an obstacle, and quickly return to their working position.

The concave disc bearings are designed as maintenance free so there is no need to grease or adjust them.

The Rubin’s design allows space between the disc and stalk enabling soil to pass through easily.

An internal six-fold cassette sealing ensures protection of the bearing against dust and moisture.

An impact harrow behind the first row of concave discs guides the soil flow and slows it before the second row.

A leveling harrow behind the second row of concave discs leaves a flat surface.

A self-locking device allows the easy adjustment of the working depth of the harrows.

Both harrows feature central depth adjustment. The depth indicator is integrated into the frame and can be easily read from the tractor cabin.

The Rubin 12 comes rigid or semi-mounted – on rigid implements the working depth is adjusted either hydraulically or with a series of holes, while the working depth of the folding and semi-mounted is adjusted hydraulically.

The folding semi-mounted models have five, six and 7m working widths and are equipped with following rollers with pendulum suspension.

A short distance between the coupling points and the wheels allows the semi-mounted Rubin to be easily manoeuvred.

The LEMKEN Rubin 12 disc cultivator is priced from $40,545 plus GST for the 3m linkage model.

A LEMKEN Karat 9 fitted with a roller was also showcased at the demo day. The model had inter-row spacing of 250mm and came with the option of 30cm wide blades.

“This is a primary tillage tool for making sure we can remove all the cotton trash - there is a wedge on the back of each tyne so you can quick-release it to change them over,” Wensing said.

“The row of discs on the back purely level out the furrows from the last row of tynes and the roller allows wheat to be drilled directly behind this with one pass.

“Our aim with both machines is turn this country around so growers could go behind a single pass and sow wheat in the knowledge the ground has been pupae busted, levelled out and created a bit of tilth for the seed."

Look up LEMKEN tillage and seeding equipment for sale

Working width (cm):  400

Tractor output (hp):180-320

Weight (kg): 2616

Discs: 22

Disc diameter (mm): 736