Compaction Concerns Contribute to Applicator Design
Even weight distribution is the Holy Grail for applicator manufacturers. Several manufacturers claim one or more models/configurations within three to four percent or less of even weight distribution. As tank volume and booms increase in size and weight on a given model, the variance tends to increase as well. A critical point in evaluating distribution is that it stays relatively the same as the tank goes from full to empty.
PHOTO COURTESY OF AGCOAll-wheel steering offered by manufacturers keeps front and rear wheels traveling in the same track for compacting soil in only one wheel track. For Case IH, Hagie and Miller St. Nazianz, the road to less compaction led to a center-mounted tank with the cab at the front balancing the engine at the rear. From there, the three diverged with Case IH putting the boom to the rear and Hagie and Miller placing it at the front. Hagie's lightest weight sprayer utilizes two 500-gallon saddle tanks as part of its compaction reduction effort.
AGCO sought improved front and rear parity with its 2012 introductions by moving the front axle back a little more than 10 inches to put more weight over the front end. This, along with other changes, puts the front-to-rear weight distribution for the RG900 RoGator with a 90-foot boom in that plus or minus three percent ratio.
Distributing each wheel's weight over the greatest footprint is also important, suggested Paul Haefner, business development manager for the Northwestern U.S., AGCO Application Equipment. "It is best to minimize compaction where you can," he said. "One way is with tire pressure and ground contact area. With the VF tire from Michelin, we can run at 34 pounds versus 62 pounds pressure, giving us a wider, longer footprint within the row, yet running safely on the road."
Burns noted that an increasing number of customers are ordering Case IH applicators with two sets of tires. "They like wider tires for spring application when soils are wetter and there is more concern over compaction, but less concern over staying between rows," he said. "They switch over to narrower, conventional row-crop size tires later in the season."
Compaction concerns are also contributing to rapid adoption of all-wheel steering, noted Criddle. "We already had the tightest turning radius in the industry, but our customers said that didn't translate into minimizing compaction," he said. "They wanted a machine that would track rear to front to truly minimize compaction."
REDUCING CROP DAMAGE
When AGCO first introduced all-wheel steering, GatorTrak, it found a niche market in cotton production states. Now interest in reducing compaction and crop damage at the headlands is driving demand in the Corn Belt as well.