Even routine repairs beneath a continuous-flow, in-bin dryer can be dirty, difficult and dangerous work — better suited for a contortionist than a farmer. Yet, a simple “floor lift” transformed what was once a beastly working environment into one that is now comparatively attractive for Clay Mitchell and his father, Wade, who grow corn and soybeans near Waterloo, IA.
Rather than having to regularly encounter an ugly and awkward work space to perform maintenance throughout harvest, the Mitchells decided to raise their perforated, drying bin floor 3½ ft. in 2005, giving them 5 ft. of total clearance. “The elevated floor allows easier servicing of the drying machinery, regardless of whether grain is in the bin or not,” says Mitchell. “Even when the drying bin is full, you can monitor and service everything conveniently.”
Raising the floor proved to be economical as well, requiring only about 120 man-hours, good welding skills, some steel I-beams and several handfuls of nuts and bolts, he points out. While fairly simple and low-cost to implement, Mitchell notes that the benefits from the floor lift have been attractive ones.
Constant cleanliness is just one example. “(The extra headroom) gives us easy access to clean the dust, grain particles and fines from underneath the drying floor,” says Mitchell. “It also helps to keep insects out during storage.”
Easier access under the drying floor also encourages more consistent monitoring and greater bin safety. “It lets us remove combustible materials more easily,” says Mitchell. “It also reduces the risk of bin fires and allows us to use higher temperatures without as much worry.”
Several thermocouples track the air temperature in the chamber below the drying bin floor and within the grain itself. The sensors help to keep the Mitchells informed about drying conditions via their laptop computers and wireless network, even while driving a tractor or combining crops. If the sensors detect a problem, they can investigate and make changes before any costly damage occurs. Keeping the area clean under the floor also helps to reduce moisture buildup and minimize rust problems inside the structure.
The Mitchells rely on three industrial blowers to provide negative airflow from the augers and the grain leg and to vacuum out chaff and dust through plastic tubing. The tubing leads to a covered grain wagon, which can be easily transported and dumped away from the grain bins.
In the past, the pounding from the floor auger feet tended to loosen the self-drilling screws that held down the flashing and auger tracks. The Mitchells replaced those screws with grade-eight nuts and bolts that are much easier to tighten or replace from below — even if the drying bin is full.
Floor augers are also positioned in an adjacent grain cooling bin. The floor augers in the drying and cooling bins, when combined with dedicated conveyors from the dryer to the cooler, and from the cooler to various storage bins, create a continuous-flow drying and cooling system.
The storage space lost when raising the floor was more than compensated for by the increased drying capacity resulting from continuous-flow drying and cooling, says Mitchell. He adds that the throughput was actually increased by a factor of three.
“During harvest, grain handling and monitoring is continuous,” he says. “It's almost a full-time activity.”
With so much time and attention focused on the crop's wellbeing at harvest, it helps to have safe and easy access to the inner workings of the drying bin. To accept anything less would be just plain ugly.