Many augers are designed to perform best at a 35° angle. Others, such as the 16"-diameter Backsaver Auger from Farm King have a 44° angle. Either way, augers must be sized to slope along the top of bin eaves without bumping into them.
Move your grain with confidence and efficiency
One of the best ways to carry corn and soybeans to the finish line is a portable auger. It sounds easy enough, but miscalculating factors such as length, capacity and crop condition can result in excess downtime and poor grain quality.
"There are farmers who want to get the best buy possible," says Dave Ulrich, owner of Ulrich Sales, an auger and conveyor specialty store in Cedar Falls, Iowa. "Do you want the cheapest you can get, or do you want to get the best for your dollar for what you need?"
To avoid a costly mistake, here are six steps to guide your decision when matching an auger to your operation:
Measure the bin. Arriving at the proper auger size begins with an evaluation of your grain bin system. Measure the tallest bin on your farm or determine the tallest bin you expect to have based on expansion plans. Be sure to add in the height of the platform on which the bin stands.
The next step is to identify the height of that bin’s eaves, says Lee Yarrow, sales engineer for Hutchinson/Mayrath. In general, an auger will best fit a bin at a 35° angle, so the auger needs to be long enough to reach over the eaves, but not bump into them. Be aware that the ground under the auger tends to slope away from the bin.
Finally, factor in the diameter of the bin. For example, a bin with an eave height of 35' and a diameter of 17' would require an auger length of 61', says Greg Giesbrecht with Westfield Industries, which manufactures portable augers under brand names Westfield and Wheatheart.
Consider capacity with grain type. Augers handle corn and soybeans differently, meaning the capacity of grain that can be moved in an hour varies significantly.
Augers are generally rated for dry corn, so if an operator expects a wet crop, it’s a good idea to step up the auger diameter from 8" to 10". Farmers are increasingly moving to auger diameters of 13" and even 16" to handle more volume. Horsepower requirements also increase for wet crops.
Because of their round shape, soybeans don’t flow as smoothly as corn, adds Ulrich, who manages his family’s 400-acre corn and soybean operation. If a farmer moves 100,000 bu. of corn in a year and 25,000 bu. of soybeans, Ulrich multiplies the soybean total by seven—equivalent to 175,000 bu. of corn—to present customers with an accurate picture of the resulting wear and tear.
As a rule, a 10" Westfield auger can move about 6,500 bu. of grain per hour at 540 revolutions per minute (rpm), Giesbrecht says. A 13" auger will move 11,000 bu. per hour, and a 16" might move 23,000 bu. per hour. "A smaller auger might have the capacity to move the bushels per hour, but if they have high volumes, they might want to use a larger auger just because it will run less time and you’ll get more life out of it," Yarrow adds.
When choosing an auger, first calculate the height and diameter of the tallest grain bin on your farm.
Power up (or down). Whether powered by a tractor PTO, an electric motor or a gas engine, an auger’s ability to move grain depends on its diameter.
On the smaller end of the spectrum, an 8" or 10" auger requires a minimum of 50 PTO hp to 60 PTO hp, Giesbrecht says. On the larger end, a 16"-diameter, 125' auger needs up to 250 PTO hp.
Most augers are designed to run at 540 rpm, so it’s important to use the appropriate tractor. If a tractor is designed to operate at 1,000 rpm, a reducer should be used on the gearbox to cut the number of revolutions to 540, Giesbrecht says.
Farmers who want to use electric motors should verify they have access to the needed power source. Single-phase power can be used for a motor of up to 15 hp, but three-phase electricity is needed for motors with a higher rating, Yarrow explains.
Size up hopper height and options. Don’t forget about the hopper, which acts as a relay between grain wagons and the auger. Each manufacturer provides hoppers with different heights; the lower options are typically preferred, Giesbrecht says.
Options can also make hoppers work more efficiently. For example, a power swing allows the operator to move the hopper remotely, speeding the unloading process. Bin hoppers can be fixed to an auger for heightened efficiency compared with a poly hopper, which must be strapped to the auger, he adds.
Weigh the costs. As with all farm equipment, cost depends on size and options. A 61' Westfield auger costs between $12,000 and $15,000. A larger auger can cost as much as $68,000.
At Hutchinson/Mayrath, 6"-diameter units can run between $4,000 and $6,000, Yarrow says. A larger 13"-diameter auger can run between $20,000 and $30,000.
Another cost consideration: dealer proximity and support, Ulrich adds. Producers might be tempted to purchase an auger at auction only to discover that the nearest dealer support is 100 miles away or more.
"We have racks full of every chain, every sprocket, every pulley, usually 30 gearboxes on hand, and we have every PTO," Ulrich says.
Inspect the equipment. It might make sense to buy a quality used auger versus a new one. Ulrich recommends first reviewing the exterior for damage that shows how hard the previous operator ran it.
"Look to see if all the components have both fresh and residue grease," he says. "The presence of both means that the owner cared enough to keep it well lubed."
Common problems with used augers include dry hubs, stretched chains, worn bearings and gearboxes in need of rebuilding.
"The vast majority of expensive breakdowns farmers have are preventable if they would actually walk through all the pieces on their machine," Ulrich notes.
Size: Choose an auger length based on maximum bin height (also factoring in the platform), bin diameter and ground slope. Select a diameter based on needed capacity, with 6" at the low end for smaller volumes and 16" on the high end.
Speed: Auger diameter and angle affect the rate at which grain enters a bin. Moving a lot of grain? Consider a larger-diameter auger at 540 rpm for more than 20,000 bu. per hour. Moving a little? The same speed with a smaller-diameter auger can move approximately 6,000 bu. per hour.
Condition: Consider going up a step in auger diameter (e.g., 10" to 13") if you’re pushing your current auger close to capacity and your crop generally comes in wet from the field. This will ensure the speed you’re seeking without damaging the auger.
You can e-mail Nate Birt at email@example.com.
For more details on matching an auger to your grain-handling needs, including a calculator that figures auger length, flight speed and ground length, visit www.FarmJournal.com/augers
- February 2014