When is high not high enough? | When new corn varieties produce taller stalks, axles need to follow
FARGO, N.D. — The term “high clearance sprayer” takes on new meaning when these machines fight to stay atop corn hybrids that have recently gone from six to eight feet tall.
Hagie is one of the companies trying to keep up with the higher crops. Its new STS12i sprayer, which it debuted at the Big Iron show in Fargo earlier this year, now has 73 inches free clearance.
“We came out with what we call our tall corn package a while ago,” said company rep Eddy Roesch.
“We shell the entire under belly of the sprayer with panels to let the tops of the plants flow past without snagging anything.”
The aluminum spinner hubcaps installed on the display sprayer were reminiscent of the “moonie” hubcaps installed on Bonneville Salt Flat hot rods.
Roesch said the idea is much the same. Smooth lines make all the difference, whether you want smooth air flow at 200 m.p.h. or smooth biomass flow at 15 m.p.h.
“That’s all part of the tall corn package. The aluminum spinner hubcaps guide the corn plant past the wheels with the least amount disturbance or damage to the foliage or tassles,” he said.
“The (nitrogen tool bar) is another option we’ve added recently to address tall corn. Dribbling N between your corn rows is not the best way of applying in-crop nitrogen. Dribbling works, but actually putting nitrogen down into the soil works better. More than 90 percent of the nitrogen needs come after the corn is knee high. The taller the corn, the harder it is to make that application. So our NTB (nitrogen tool bar) uses coulters with high pressure injection to place your nitrogen into the soil between the rows.”
Roesch said the small case letter “i” on the STS12i designates product injection.
The new sprayer carries 240 U.S. gallons of injectable chemical on the machine. There are two 60 gallon and one 120 gallon product tanks.
Each of the three product lines is independent of the others, with its own injection pump and metering system.
This eliminates the need to pre-mix large volumes of chemical in the main 1,200 gallon water tank. The main water tank holds only clean, uncontaminated water.
“You can switch products pretty easily going from one field to the next,” he said.
“You never have any leftover mixed product when you finish a field, and you don’t waste time rinsing changing from one crop to the next.”
Spray efficacy is enhanced by the standard equipment droplet monitoring system, which gives the operator the ideal droplet size based on spray tip size and pressure.
The basic STS12 chassis was upgraded this year, but there are still a number of changes. The 2015 sprayer is powered by the Cummins 6.7 litre Tier 4 final, putting out 300 horsepower. The power now runs through a new infinitely variable drive system.
“You not only choose how fast you want to spray, but you also choose how many shift points you want to get up to that speed. If you want 20 shift points to reach 15 m.p.h., that’s what the machine gives you.”
The sprayer is hydrostatic all-wheel-drive with traction control.
The cooling system now pulls clean air from the top side of the machine, so plugging is less of a problem. The standard equipment hydraulic drive fan is reversible to clean out the air path and improves fuel economy by as much as 15 percent, according to Hagie.
Fresh air for the operator is also essential. The new Hagie cab comes standard on all models with the Sy-Klone RESPA air filtration system. All sprayers also come standard with a back-up camera.
The STS16 prototype for 2015 that Hagie brought to Big Iron uses the same frame as last year but with a Cummins 365 h.p. engine, the new Hagie cab and changes to the hood and tank placement.
The 1,600 gallon sprayer has an all-new drive system, keeps the perfect 50-50 front-rear weight distribution full or empty and has been been fitted with giant brakes at the front.
“We’ve installed huge disc brakes on the front wheels for excellent stopping. We’ve got big rotors with two callipers on each rotor. These are the squeeze type callipers with a piston on each side rather than the slider type,” he said.
“There’s no hesitation or confusion in an emergency stop because it’s all tied into the operator’s hydro handle in the cab. The (deceleration) pedal helps you boost headland turning efficiency. They haul the sprayer down in a big hurry.”
The 800 metric tires on the option list give Hagie a much heavier leg design as standard equipment as well as a severe duty suspension option. The severe duty suspension uses a solid inner leg and thicker wall out leg, along with higher load rated hubs.
Roesch said the 800 series tires and the rubber track option, which is new for 2015, are the two main reasons for heftier legs.
Rubber tracks are high on the option list for farmers with soil compaction issues. The downside of rubber tracks is that maximum ground speed in the field is limited to 14 m.p.h., while road speed is limited to 20 m.p.h.
Hagie says an empty sprayer with 50-50 distribution exerts a down force of 25 pounds per square inch with 380 tires, while the sprayer exerts a force of only 9.8 p.s.i. with metric 800 tires.
However, the same sprayer with 15-inch-wide rubber track puts down only 8.4 p.s.i.
In comparison, a human boot print exerts five p.s.i. Hagie says compaction caused by as little as four p.s.i. sacrifices yield.