Large-scale spraying solution

By: Brent Lilley, Photography by: Brent Lilley

Date: 28.03.2012

Agricultural sprayers have come a long way as Farm Trader’s Brent Lilley discovered when he flew south to test out the Househam sprayer on a paddock of maize

Large-scale spraying solution

The machine tested was a new Househam AR3000 sprayer, owned by Hyde Brothers Spraying of Canterbury. The test took place at Hinds, mid Canterbury, and the job at hand was a post-emergence spray of 20 hectares of maize at an application rate of 150 litres/ha. Typical of Canterbury, it was a perfectly flat and square paddock.

When I got there Simon, the driver, had just finished filling the sprayer with water and mixing the chemical in. Everything was located on the left-hand side of the machine, with a flexible length of suction hose coiled on the side for filling and a control panel to manage all the operations needed for filling and mixing the chemical. Combined with the control panel is a decent-sized storage locker for safety equipment and clothing. There is also a tap from the clean water tank for hand washing.

The 25-litre stainless steel chemical induction hopper is located on this side of the sprayer next to the control panel and drops down to waist height for easy filling. A great idea that is incorporated into the induction hopper is a spray jet and an empty chemical bottle washer. A sight glass on the main tank located next to the induction hopper also makes filling to a desired level very straightforward.

Operation
Operation of the sprayer was really quite simple: the booms are unfolded with a switch in the cab and then set to the desired height with a switch also on the control panel on the right-hand armrest of the operator’s seat. The type of nozzle that is being used and the target application rate are programmed into the TMC (total machine control) monitor. With the machine in field mode, the electronic park brake is released and the joystick is simply pushed forward to move. The spray is turned on or off at the desired spot, with the master control switch on the joystick that can be turn off in sections.

Twin Ramsey valves on the machine control the flow rate to match the ground speed, achieving the desired application rate that is programmed into the computer. There is a direct sensor on the flow rate and the TCM will display the target application and the achieved rate. This can alert the driver to problems such as blockages and is surprisingly accurate.

The first pass around the paddock is definitely the hardest part of the job: unless it is stored in the GPS from a previous visit, the end of the boom seems a long way from the cab and rather close to the fence. This was easier when following the maize rows than it would be on some other crops. Once the boundaries have been set on the Fieldmaster GPS the job gets much simpler, with a light bar and a graphic display to show you the correct line to drive in. When spraying the land, the machine will automatically start and stop the spray on the headlands with great accuracy, thanks to the GPS and the air shut-off nozzles.

This sprayer was also fitted with an eight-section boom control that can be manually controlled or will auto shut-off using the GPS, which would be particularly handy when spraying odd shaped paddocks. With little effort we managed to spray the 20 ha of maize in around 40 minutes, although I’m sure it took longer with me there.

Once the job is finished, the sprayer is very easily cleaned and flushed out: as the spray lines are recirculating, they can be flushed with water from the clean water tank while sitting in the cab.

The machine
The Househam AR3000 is in the mid-range of self-propelled sprayers that the company builds. It uses CAT engines in all its sprayers; this machine had a 6.6 170hp turbo CAT engine. The components that make up the sprayer are all mounted on a very robust looking steel chassis, which in turn is mounted on active air ride suspension that gives the machine good stability in the paddock and on the road. The air suspension gave an excellent ride and will be appreciated by those spending long hours in the sprayer.

The wheel track width on the sprayer can be hydraulically adjusted between 1.83 and 2.13m from a switch in the cab. This will improve the flexibility of the machine when spraying different crops and on different properties.

The boom pump and tank
Like most sprayers, there are full-range boom and tank options available on the sprayer – this machine was running a 24-metre variable geometry boom. Variable geometry enables the tilt of the boom on either side of the machine to be altered independently. On this machine, it could be adjusted manually from inside the cab, but an option of ultra-sonic boom levellers is available to maintain the boom position from the ground.

The boom is very well constructed from steel box section with stainless steel spray lines and triple body nozzles. The spray lines are recirculating with air shut-off nozzles, meaning the spray is always at the nozzle and will stop and start spraying instantaneously.

The standard pump for the machine is a four-cylinder 270 litres/minute Altek pump, but this machine was fitted with a larger six-cylinder 380 litres/minute Altek. Househam uses Altek pumps on its machines because it believes they are very robust and reliable, giving a long service life.

The tank on this machine was a 3000-litre Glass reinforced plastic tank but stainless steel is available as an option.

The cab
The cab on the machine is very spacious, with plenty of glass for great visibility. The driver’s seat and steering column are positioned in the centre of the cab, with room for all the sprayer controls and joystick located on a console built into the right-hand armrest of the driver’s seat. Two separate monitors are mounted at eye level on the front right-hand pillar of the cab: one for the Fieldmaster GPS and the other for the TMC, which displays all of the operating information for the machine. To the left of the driver’s seat there is plenty of room for storage and a passenger’s seat, which is positioned low to keep annoying passengers out of the operator’s vision!

The cab has air conditioning with carbon filters to keep the chemicals out and the air clean. Electric mirrors also save climbing about on the outside of the machine to adjust them.

The verdict
A self-propelled sprayer is a huge investment to make, but the Househam AR3000 sprayer is a massive leap forward from some outdated spray rigs still in use today. With large scale farmers and contractors always needing to spray for more hours than there are in a day, when conditions are suitable, it makes sense to invest in a purpose-built machine like the Househam AR3000 sprayer, built by a company that solely builds spraying equipment.

With the Fieldmaster GPS for guidance and auto on/off for the spray, operation of the machine is made very simple. The hydraulically adjustable wheel track width offers greater flexibility for the machine to be used in different situations, and the air ride suspension will offer an attractive benefit for those spending long hours in the cab.

Overall, it is a well thought out machine, built and designed to a very high standard.

Positives
Air ride suspension gives a very smooth ride
Recirculating spray lines on the boom
The Househam sprayer is a purpose-built machine.

Negatives
As with all self-propelled sprayers, the max road speed is 40kph, which would be a disadvantage for those with a lot of ground to cover or with a truck-mounted sprayer.

Specifications
Engine   CAT 6.6L, 170hp turbo-diesel, Tier III
Transmission  Fully hydrostatic 4WD, low, medium and high ranges
Steering   Selectable 2 or 4-wheel steering
Suspension   Active self-levelling, load compensating air suspension
Tank    3000L glass reinforced plastic tank
Pump   4-cylinder, 270L/min Altek pump
Boom    24m tri-fold with hydraulic fold, lift and tilt
Ground clearance 890mm
Wheel track  Adjustable from 1.73 – 2.03m
Fuel tank  200L plastic tank
Max speed   40kph
Unladen weight 6500kg
Overall width  2.8m
Overall height  3.6m
Overall length  7.5m