Farms are increasing in size and bigger farms demand bigger implements. Therefore, Kuhn built a new self-propelled sprayer. This sprayer is popular all over the world, and is also steadily gaining a firm foothold in South Africa. Valtrac, the reputable provider of agricultural equipment, is the importer and distributor of this standard setting sprayer.

The Kuhn Stronger HD 4000 was launched at NAMPO this year, and its sturdy 36-metre aluminium beam stretched almost across the whole Valtrac stand. Tokkie Nel, a farmer from the farm, Krom Elmboog near Newcastle, bought the first Stronger. The healthy crops on his farm bear testimony of the wisdom of his choice.

The most exciting and revolutionary feature of this sprayer is the Bosch electronic propulsion system. Stronger is the first sprayer to use this propulsion system to control everything from wheel slip, engine revolutions, and pump pressure (by adapting engine revolutions) and it is the main reason for the astonishingly low fuel consumption of the 4 000-ℓ sprayer.

The Trimble GPS system is equally advanced and is built onto an Android platform. This allows the farmer to connect to the internet should he need Valtrac’s technical team to gain entrance to the system. Trimble’s recapitulation is superb – the sprayer will follow precisely in its previous tracks every time. This ensures minimum damage to Tollie’s soya beans, maize and wheat.

The 36-metre beam works very well with his 12-metre planter and spends much less time in the crops than his previous sprayer. “The sprayer causes far less damage to the crops, and due to the wider beam, we cover a field in fewer runs. This saves diesel and labour,” says Tollie’s farm manager, Willem Botha. They also use the sprayer to apply fertiliser and other plant nutrition.

Apart from the fewer runs needed, the Stronger 4000 uses dramatically less diesel than its predecessor. “The Stronger uses 500 to 700 ml of diesel per hectare, depending of the wetness of the soil. Our previous sprayer had a shorter beam and used a litre of diesel per hectare,” says Willem.

The section control of the beam is divided in 9 sections and every four-metre segment controls itself independently. This ensures that the spray supply is cut off immediately so that no unnecessary spray runs down the system.

Willem Botha, Farm Manager on Krom Elmboog, shows how he can remove his hands from the steering wheel while the sprayer turns around at the headland and accurately follows the return track of the next run all by itself.

Valtrac also offers a revolutionary twin-header sprayer system. This inexpensive option was developed by Kuhn and can be added on order. When the sprayer moves slowly, the finer sprayer is activated, and when it accelerates, it switches over to the larger sprayer head to apply more spray. At an even higher speed or when high volumes must be applied, both sprayer heads are activated. This system ensures uniform drop size at various working speeds at about a third of the cost of other technology for the same function. Moreover, there is the benefit of lower maintenance costs as you may still use your standard sprayer heads. The twin sprayers work astonishingly well and effect a very even application. Also, the sprayer heads do not protrude from under the beam.

The beam is kept stable by Kuhn’s floating beam balance mounting. The oil accumulator and a return spring on the beam work together to restrict damage to the minimum in the rare event of hitting an obstacle.

All parts of the Stronger 4000 that come into contact with the spray are made of stainless steel, including the 4 000-litre tank and the centrifugal spray pump that can displace 600 litres per minute. With this pump, you can easily fill the tank within four minutes. The stainless-steel tank lasts much longer than a plastic tank and does not crack so easily. Also, it is easier and quicker to clean as nothing can permeate the tank walls. The size of the 4 000-litre tank reduces the number of refill runs, thereby saving even more time and fuel. The life of the sprayers and hoses is extended due to the 400-litre onboard clean-water tank that can be used at the end of a shift to properly wash and rinse the whole tank and sprayer system.

This modern machine is fully four-wheel drive and all the wheels are driven hydraulically. All the hydraulic drive system’s components are electronically controlled, and wheel-slip is controlled separately on every wheel. When one wheel begins to spin, the oil flow to that wheel is reduced until the wheel-slip on all the wheels are balanced again. The same thing happens when braking – then the hydraulic anti-lock braking system comes into play. With all this information at its disposal, the diesel engine can regulate itself to work at the most suitable revolutions to attain the lowest fuel consumption and the highest efficiency, even in difficult conditions.

An intelligent hydrostatic gearbox continuously transmits the correct amount of power to this advanced system.

The sprayer has no accelerator pedal, in fact there is no work for your feet and everything is done with a control arm. When you push the control arm forward, the engine starts turning at 1 600 revolutions per minute. As the speed increases and more power is needed the revolutions go up. That is the reason why the Stronger 4000 works so frugally with the fuel.

On the road, the sprayer effortlessly runs at 30 km/h and in the field an efficient, comfortable spraying speed of 15 km/h is maintained. To brake, simply pull back the control arm. The beam functions are also controlled with buttons on and next to the control arm.

Al the functions of the sprayer, including forward and reverse, are controlled with the control arm and console.

Returns automatically

Willem is very pleased with the sprayer’ ability to turn around at the end of the field automatically. Fortunately, the sprayer demands that you touch a button on a screen when the headland is approached to make sure that the operator does not fall asleep.

For farmers who still do not feel at ease with all the electronic technology, a mechanical pressure gauge outside the cabin can be seen from the driver’s seat. The view from the cabin is also better than in previous models and the air cushion under the operator’s seat ensures many hours of comfortable spraying. The wheel spacing of the Stronger can also be adjusted on the go from the cabin and the ground clearance under the belly is 1,8 metres.

To keep up with Valtrac’s modern implements and solutions, contact Attie de Villiers at 083-261-9863 or 056-817-7308 or Also visit

Willem Botha only has to pull a lever to drop the mixing and application tank. You may forget the tank in this position, because as soon as the sprayer starts its run, it automatically retracts into its niche in the sprayer’s body.
The 380/90-inch radial ply tyres of the Kuhn Stronger HD 4000 are narrow enough to minimise damage to crops, but big enough to ensure proper traction and riding comfort.


The sprayer’s suction pump easily displaces 600 litres per minute to the 4 000-litre tank.