Grain Dryer Maintenance: Clean and Inspect Components Before Harvest to Sustain Optimal Performance

From the July/August GRAIN JOURNAL

Al Arndt | District Sales Manager | Brock Grain Systems | Milford, IN

“When it comes to grain dryer maintenance, there are several tried-and-true techniques that will keep them running in top condition. Start by making sure all the bearings are lubricated, and check all the belts for tightness and wear. Also, inspect the dryer gas connections to ensure they are completely tight and not leaking. It’s also important to do a general visual inspection of the dryer for missing bolts, screen breakages, and so on. Any foreign material should also be cleaned off the dryer, because they start to take abuse if they aren’t cleaned from year to year.

“Check all the wiring and ground connections for tightness and corrosion. Also, check all grain handling equipment to make sure it’s in good condition. Make sure that the burner is clean and the port holes are free of debris, and test the dryer to make sure all electrical and gas components work correctly.”

Kerry Hartwig | Dryer Sales Director | Sukup Manufacturing | Sheffield, IA

“In the spring and early summer, I highly recommend grain elevator operators do pre-season checks. Don’t wait until your wet bins are full before you find out if your burner is going to fire. Many grain handling equipment dealers offer these kinds of services, which consist of making sure fans are blowing and firing, making sure the heaters fire and work the way they c should, and making sure your unload and load systems all work.”

“As far as some other specific maintenance tips: You have to keep clean any dryer that has screens. The dryer needs to be able to breathe, and the more it struggles with that when the screens are dirty, the less fuel efficient you’re going to be and the less capacity the dryer will have.

“It also should go without saying that clean dryers are much less of a fire risk than those that are not kept clean.”

Nathan Fries | Project Engineer | Chief Agri | Kearney, NE

“Generally speaking, good housekeeping is critical to safe dryer operation, so it’s important to always be diligent about clearing debris as it builds up on any interior or exterior dryer surfaces and components to help prevent fires.

“There are a number of best practices when it comes to proper grain dryer maintenance, and we break them down by pre-season, in-season, and post-season or general maintenance, some of which should be done daily, weekly, or quarterly.

“Prior to harvest, be sure to clean the dryer thoroughly, and lubricate all necessary components, including greasing all the bearings on fans, augers, etc. Re-install any doors on the dryer that were removed, and open the manual gas valve and inspect the gas train for any issues or leaks.

“For in-season maintenance, the following service should be done on a daily basis: Inspect and clean plenum interior for excess buildup; verify gas/oil pressure; verify air compressor is on and pneumatic discharger panel has sufficient air pressure; check levels of anti-freeze in line, if applicable; inspect discharging grain for consistent hopper fill levels and signs of trash buildup in discharger troughs; verify dust auger/air locks are clear from debris, if applicable; inspect and maintain dust filters or dust fans.

“We also recommend leaving the dryer full if drying is going to continue within a few days. This will help with the drying cycle by not having to recycle the bottom grain back to the wet holding tank. It also prevents the debris that has hung up on the laterals during drying from being blown down to the discharger of the dryer. Once the dryer has been unloaded, we recommend inspecting the discharging troughs/openings and cleaning if necessary before refilling.

“Every week during season, it’s also important to inspect pneumatic components for leaks or potential failures and to inspect the gas train for any leaks. We also suggest cleaning gas strainers (Y-strainers) and/or traps during this time. Finally, inspect reserve section c for any excess debris.

“During post-season, we recommend cleaning the dryer thoroughly and removing any and all trash or debris build-up on all dryer surfaces. Be sure to thoroughly clean the interior plenums area including on movable doors and dust auger as well. Remove the bottom hopper access doors to make sure the discharger is free of debris and working properly. Be extremely cautious and careful when working with the discharger and any part of the pneumatics as there are many pinch points and the possibility for injury. Always use proper lockout/tagout procedure and remove system pressure to prevent trapped potential energy in the pneumatic system.

“Also during post-season, continually supply 120V power to the panels. This will ensure that the panel heaters will run as needed and prevent any moisture buildup inside the panel

“Other than that, we recommend changing the PLC battery every three years. When doing so, it’s important to not remove the EPROM chip from the PLC unit. Otherwise, the program may be lost and the dryer won’t continue to operate.”

Randy Sheley | Grain Conditioning, Product Specialist | GSI | Assumption, IL

“When it comes to grain dryer maintenance, there are a few simple rules of thumb for ensuring they perform optimally. The first thing is to keep the dryer clean, especially when drying high-moisture corn. Outside screens can accumulate debris and fines quickly. If allowed to accumulate, the screens will become plugged and hurt the efficiency of the grain dryer. Eventually, the capacity of the dryer will drop.

“Fines tend to start collecting near the top of the dryer and work their way down. If you take the time to clean the top before the buildup continues down the dryer, the efficiency and capacity loss will be minimal.

“The best-known way to clean screens is with a power washer, but brushing with a broom is acceptable.

“Grain turners should be inspected and cleaned on a regular basis, especially when drying soybeans. Soybean pods can and will plug grain turners and can lead to dryer fires. The plenum divider hopper also needs to be inspected regularly and cleaned if necessary. Neglecting the plenum divider also can result in dryer fires. While inspecting the plenum divider hopper, be sure to check the inside dryer screens. They typically don’t accumulate debris or fines, but if they do, it would be a good indication that the entry hatches to the unload section are not sealed properly.

“Next, it’s important to cali- c brate dryers cautiously. If your dryer is equipped with moisture controls, it’s important to keep the moisture sensors calibrated with a trusted table-top moisture tester. Check the moisture on a set schedule, but only change the calibration of the dryer if a trend is observed.

“It’s also important to calibrate the dryer only when the target moisture (as checked by the trusted tester) is being discharged from the dryer. All testers use capacitive testing but not necessarily the same circuitry and software, so they won’t match at every point on the moisture curve. It’s only important that they match at the target moisture. When sampling grain, take small handfuls every 10 seconds or so over a minimum of a few minutes to ensure a representative sample.

“Lastly, it’s very important to be patient. When adjustments are made, it can take up to several hours to see the results at the dryer discharge. If a dryer is over-adjusted, it will discharge grain with big swings in moisture level. If a change is made to either the dryer unload speed or plenum temperature, stay with that adjustment until the discharge grain moisture levels off for at least 30 minutes. If further adjustments are needed, make them small and, again, wait for the grain to work its way through the dryer. With experience, larger adjustments can be made, but it’s important to always wait for any adjustment to work its way all the way to the discharge.”

Ricardo Reggeti | Regional Sales Manager | Mega Dryers | Wichita, KS

“One of the things that comes to mind first is to maintain a good grain flow through the grain columns, regardless if it is a cross-flow or a mixed-flow dryer. With most of the dryers, if you don’t have good grain flow, the grain doesn’t get dried uniformly.

“I also suggest making sure that your burner and combustion systems are well calibrated and working efficiently, and verify that you are maintaining the proper drying air temperature for that particular commodity.

“Also, it is important to continuously be monitoring the air-drying temperature and the grain temperature during the drying process. If the operator is constantly monitoring the temperatures inside the dryer, he will be able to notice any problem areas, such as a change in temperature that could represent a hotspot or a potential fire hazard.

“In preparation for harvest, make sure that there are no obstructions inside the grain passages that can lead to problems later on.”

Todd Muller | Sales and Marketing Representative | Ag Dryer Services Inc. | Elm Creek, NE

“Our absolute most important maintenance tip is to clean your dryer. Keep out any dust or excess grain, and then cover your burner when not in use to prevent dust and debris buildup.

“Additionally, keep the main doors closed on your power doors to keep all your electric components dry and as clean as possible.

“The reason general maintenance, especially cleaning, is so important is because of safety. Dryer fires are typically caused by lack of maintenance. Something as simple as cleaning your dryer can save a lot of headache as well as money down the road.”

Merle Lantzer, Engineer | Jesse Weaver, Engineer | Delux Manufacturing, Co.| Kearney, NE

“One of the keys to optimal dryer performance is the burner system. Cleaning the burners and maintaining the burner control system, igniter, and flame sensors are very important. This area is the heart of the drying process.

“Another big area is the electronic controls – they need to be protected from the elements. The control boxes are rated to protect this equipment, but you need to keep the doors closed. It’s easy to forget to close all the latches, which can lead to dirt and moisture contamination.

“In tough drying seasons, operators tend to push for more capacity, and sometimes maintenance gets put on the back burner. That really opens things up for potential problems. Even if it’s tough drying, you still have to take time for maintenance. Sometimes shortcuts lead to breakdowns, which just makes the situation worse.”

Wayne Leuning | Secretary and Treasurer |D&W Industries, Inc. | Sioux Falls, SD

“When it comes to grain dryer maintenance, the biggest thing is the c cleanliness of the dryer. It’s also important to run clean product through the dryer. If you prioritize these two things, your dryers will run pretty smoothly.

“It’s easier said than done, but cleaning them on a weekly basis in season will ensure they perform optimally and will help avoid any problems. Also, make sure all of your safeties are working on your dryers.

“These tips are pretty basic, but following them should prevent problems down the road.”

Dave Grill | Quality Control | Mathews Company | Crystal Lake, IL

“First of all, stay on top of general housekeeping: Make sure everything is clean and lubricated. Use the operator’s manual to know how often housekeeping is needed.

“Then, check the different components that make up the dryer. Look at the quality of the screens, make sure there aren’t any leaks. If the screens are galvanized steel, check for any rusted areas.

“Also, check auger flightings for wear. Check belts, chain drives, and gearboxes. The operator’s manual will recommend a particular oil and frequency for lubrication.

“Make sure to maintain the working environment around the dryer to ensure that any debris from the previous season is cleaned up.

“Then, after all of that is done, it’s time to test fire the dryer. With most dryers, there are a number of things that can be live tested. The fill system can be run, even though you aren’t putting grain in it. I always like to check the amperage loads of motors while I’m doing this and then compare it to the full load amperage of the motor. If a motor is wearing out, usually as a result of bearings, the amp draw and the sound will clue you that maybe the motor needs work. It’s much better to find these problems before the heat of the season, obviously.

“The same goes for the discharge system – whether it’s a rectangle-shaped dryer that has metering rolls or a round tower dryer that has some type of a sweep system, make sure they function properly. Almost all dryers are able to vary the discharge rate, so that should be checked, and the speed should be changed accordingly. All dryers have some type of a moisture control system, and to a certain extent, there’s some testing that can be carried out on that to make sure that the automatic moisture control system is functioning properly.

“Finally, run the fans and burners. In the operator’s manual for most dryers, there’s a section on test firing a fan and burner without having grain in the dryer. Even if you can’t test fire the burner without having grain in the dryer, at least run the fan. And once again, listen for the sound it makes. It should be smooth sounding. Take amperage readings to see if there’s a problem developing with the motor.”

Grain Dryer Maintenance Top Ideas

  • Perform pre-season checks to make sure screens are clean to reduce fire hazards and do visual inspections to check for potential problem areas.
  • Prior to harvest, clean the dryer thoroughly and lubricate all necessary components, including greasing all the bearings on fans, augers, and other equipment.
  • Inspect pneumatic components and the gas train for leaks or potential failures.
  • Clear all debris on a daily, weekly, and quarterly basis and clean screens with a power washer.
  • Prevent dust and debris build-up by covering the burner when not in use, and clean burners and check the burner control system, igniter, and plate sensors.
  • Make sure moisture sensors are calibrated if your dryer is equipped with moisture controls.
  • Keep electric components dry and clean as possible, and protect the dryer’s electronic controls from the elements and sunlight.
  • Run clean product through the dryer and maintain good grain flow and a proper temperature for each commodity to make sure grain is dried uniformly.
  • Check all safety equipment.

Randy Sheley of GSI discusses tower dryer capacity issues during the GEAPS Cornbelt Chapter meeting at 4B Components Ltd. in Morton, IL.