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International Perspective: A Different Use for DirectCommand

by Apr 25, 2011International Perspectives

It is inevitable that Ag Leader’s products are going to be used in unusual situations around the globe. During our recent training for International Distributors, I got to hear of one such situation from Mac Nel, who currently works for our South African distributor. Mac has been involved in the use of a DirectCommand system on locomotives to apply herbicides. Below is his description of the problem, the solution and the challenges: 

Command center.

A customer got in touch with us and asked if we had a system that could vary herbicide according to the different speeds they would be traveling. They were particularly interested in applying the same amount of herbicide from 0km/h up to around 60km/h, with all the speeds in between. They also wanted a record of everything they had sprayed as proof of where they had sprayed and how much, as they had local government contracts to spray the train lines in certain areas with certain conditions. We told them we had a DirectCommand system that would be able to vary the rates according to their speed (at first we told them that the maximum speed they could achieve would be 40km/h, but they have successfully tested the system at higher speeds).

They were also very pleased to find out they could use the AutoSwath feature to switch sections off where the tracks had already been sprayed, especially in the train yards where there are many overlapping tracks going in different directions. Their biggest challenge was to apply 450L/ha with a train that is slow to reach full speed (50km/h), and to maintain the correct dosage without missing areas or over-applying. They use diesel locomotives that like to keep at a constant 40-50km/h, but they have to slow down when entering train yards and around towns in rural areas.To re-calibrate the whole time was becoming an issue, so they turned to us to provide them with the technology to automatically increase and decrease the amount of herbicide being applied. 

Center and side section.

They have currently sprayed a total of about 600kms worth of train tracks in and around the Gauteng region at an average of 40km/h, applying between 320-440L/ha. The maximum they have applied, using a 100-100 nozzle on both sides and a 60-50 nozzle in the middle of the train, is a rate of 400L/ha at 60km/h.” Just a couple of stats regarding the installation… “We have a DICKEY-john Flow meter and fast valve, as well as DICKEY-john section valves. We are also using an Ag Leader® Integra display with a GPS 1500 receiver with e-Dif® technology.

The power is from two truck batteries which run the entire electrical system for the train as well. There are three 50,000 litre water tanks being towed, and inside the train there are a series of pumps and actuators supplying the mixing tanks with water and the solution to be applied. The total amount of liquid for the solution tanks is around 8,000 litres.” 

Mixing tanks.


Control valves and section control.

Thanks a lot, Mac, for sharing this rather unusual application for our DirectCommand system!