There’s more to extraction than hooking and pulling
There’s probably nothing more frustrating than seeing a key piece of equipment buried up to its axles in mud. After this year’s wet planting season—and with harvest upon us—that frustration is fresh in farmers’ minds.
However, there’s more to equipment extraction than just hooking up the chains and pulling. That’s the message Fred Whitford of Purdue University conveyed to farmers at all of the 2013 Corn College sessions.
"All too often, the sense of urgency keeps us from thinking about the consequences of what could happen if we don’t take the proper precautions," Whitford said. "Extracting equipment is anything but routine, and farmers need to understand that using a cut towing strap, an undersized clevis or chain, or a weak attachment point can lead to expensive machinery repairs, injuries or worse."
Before you start pulling, first consider your environment. For instance, be aware of power lines. Make sure your actions won’t upset nearby waterways. If there are spray tanks or other components that might leak, take precautionary measures to keep everything contained.
Next, think through the four "zones" of equipment extraction.
A low-grade hook like this one will meet its match and break.
The stuck zone. As the name suggests, the stuck zone is the area immediately surrounding the equipment.
"Your first goal is to determine how much weight you need to move," Whitford advised. "Consider the total gross weight of what is stuck, including the vehicle, trailer and payload that you will need to pull."
Don’t forget to account for how deep the equipment is buried and the resistance that the stuck vehicle will encounter as it is pulled out. Mud can create its own suction, making it difficult to
extract equipment. If the machine is really entrenched, you might have to dig out around the tires and remove the ridge of soil to break the suction and allow the wheels to be lifted up and over.
The tow zone. The size of the towing vehicle depends on the weight of what’s stuck and how deep it is buried.
"It takes bulk to move hulk," Whitford said. "It’s surprising how much force it takes to unstick stuff. A good rule of thumb is that the towing vehicle needs to be of equal weight to the stuck vehicle."
Position the towing vehicle on higher ground, if possible, and make sure that vehicle is positioned to have better traction, Whitford added.
The danger zone. "It’s safe to say that there is great potential for danger anywhere around an extraction site," Whitford said, citing the common mistakes people make when extracting equipment, such as standing too close to the vehicle or using towing devices that aren’t strong enough.
If you plan to use a chain as your towing device, check its pulling grade. When you don’t know the ratings of your chains and hooks, you’re dealing with "an unknown in the laws of pressure," Whitford said. "The chain will fail when it finally meets its match."
Also, inspect the chain to make sure that it is in good condition. Don’t use chains that have stretched, bent or welded links. Even if a chain has pulled out dozens of vehicles before and has never failed, it can stretch after repeated use and become weaker.
When it comes to hooks, make sure the hook’s rating is equal to or greater than the chain’s rating.
For safety’s sake, never jerk chains or cables, he added. Clevises, hooks, hitches and chains can become deadly during failed extraction attempts. When these devices snap under pressure, they can whip through a truck windshield or human flesh in the blink of an eye.
"Chunks of metal, folks—when they come flying loose, they’re like missiles," Whitford said.
Don’t use towing ropes or straps for pulling stuck equipment. While these tools might be strong enough to pull a piece of equipment down a road, they can’t handle the torque required to extract heavy equipment from muddy conditions, Whitford said.
"Towing is pulling," Whitford said. "You don’t have to be very strong to do that."
This clevis is solid, but all of its strength is defeated by the knot in the strap.
Instead, invest in recovery ropes or straps, also known as "jerk straps." These straps are specifically designed to stretch, somewhat like a rubber band, in order to extract stuck equipment. They can handle being jerked around, Whitford said, but the best way to use them is to stretch them, and then let the strap contract and do the work.
Finally, "Be careful about how you hook up things," Whitford said. Pay special attention to the attachment points, as they have labeled strength ratings, as well. Also, inspect the strap itself for safety issues. Are there sharp edges touching it? Did you place something heavy, such as a truck floor mat, over the strap to help knock it down if it breaks? Are you able to protect your windshields in the event of a breakage?
The clear zone. You’ve checked all of the towing straps and how you’ve hooked them to your vehicles. You’re ready to tow … or are you? There’s still one final check: Keep onlookers out of the line of fire.
"Establish a circular clear zone around the entire area of at least 100' and don’t let any bystanders in that work area," Whitford advised.
Once you start pulling, remain calm. Use the lowest gear possible, try to pull in a straight line and let the towing equipment do the work.
"Resist the natural instinct to back up the towing vehicle, get a running start and yank out the stuck equipment," Whitford said. "The connection needs to be short enough that it minimizes how far debris can fly, should something break, but long enough that the towing vehicle is on solid ground. That is why it’s important to have 25' to 30' of cable, rope, strap or chain on hand."
Once you’ve extracted the stuck equipment, take a few minutes to properly inspect, clean and store recovery straps and ropes. Check for weak-nesses and tears. Inspect the equipment that was stuck for leaks or other damage.
Go Back to School in 2014
Throughout the year, you can attend a series of agronomic training events with Farm Journal experts Ken Ferrie, Missy Bauer and Phil Needham. These events include Planter Clinics, Corn College Fundamentals, Corn College Advanced, Soybean College and Wheat College.
Registration opens Oct. 1. Call (877) 482-7203 or go to www.FarmJournalCornCollege.com for dates, locations and to register.
You can e-mail Jen Russell at firstname.lastname@example.org.
To hear Fred Whitford explain more about how to safely extract farm equipment from wet spots, visit www.FarmJournal.com/stuck