George G. Maher
- Extension Agricultural Specialist
North Dakota State University Extension Service
Stuck! The tractor won't go forward or backward, and you need
help! Or, that stump or rock has got to be moved. while backing
the tractor into position for pulling, do you ever wonder,
"Is that weld repair on the hook good? What about the chain
repair we made with a bolt? what's gonna break first, the
chain or the hook?"
Think
about these questions when selecting a tow rope, chain, or
cable for pulling something. A lot of power will be attached
to whatever towing device you choose, easily stretching it
to the limit. the hook, chain or cable will become a missile
that could cause a terrible injury or death as it rebounds.
A new,
1-inch nylon rope in excellent condition has a breaking strength
of up to 25,000 pounds. New steel cable of 1 inch diameter
in excellent condition may break at 10,000 pounds, and chain
with links make of half-inch diameter material may break at
2,400 pounds. The type and size of hook that is frequently
used may break at 4,000 pounds. Whatever combination of these
materials you select for a towing device, the weakest part
always breaks first. When it breaks, the rest becomes a deadly
projectile. Parts such as ball hitches, clevises, chains and
even complete bumpers have broken loose, becoming dangerous
missiles.
Nylon
rope tends to recoil straight back to the point of attachment.
The broken hook is like a bullet. Steel cable whips about
furiously as it recoils, and chain rebounds unpredictable,
eventually winding around anything in its way. All towing
materials are dangerous when recoiling from a stretched condition
and most can go through tractor cabs and pickup window. The
result is often a serious, disabling injury or death.
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Matching the right size of towing device to the vehicle
doing the pulling is extremely difficult because of various
surfaces, soil conditions and types. Always use the strongest
and best tow rope, cable or chain available. Use the strongest
hooks that you have. Fasten them securely and be sure
that the bumper or drawbar is secure.
Always hitch to the drawbar of the tractor doing the
pulling (Figure 1). Hitching to anything other than
the drawbar dramatically increases the chance of tipping
the tractor.
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When using more than one vehicle for pulling, do not hitch
them single file, with the total effort exerted on only
one chain, cable or rope. Instead, hitch each vehicle
independently, otherwise too much power can easily be
applied to the final towing device (Figure 2). Carefully
coordinate the efforts when more than one towing unit
is used.
How can you make towing safer? First, clear the area
of people, both helpers and watchers. Second, always
hitch to the drawbar. Third, make sure everything -
bumper, drawbar, hooks, chain, cable or nylon rope -
is strong enough to handle the load. Fourth, make sure
that all attachments are secure. Finally, apply the
power smoothly without jerking - do not attempt to use
the elasticity of nylon rope to increase your pulling
power.
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For more
information on safe towing operations or more tips on other
farm safety measures you can adopt, contact your local Cooperative
Extension agent or Extension Agricultural Engineering, NDSU,
Fargo.
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NDSU Extension Service, North Dakota State University
of Agriculture and Applied Science, and U.S. Department
of Agriculture cooperating. William H. Pietsch, Director,
Fargo, North Dakota. Distributed in furtherance of the
Acts of Congress of May 8 and June 30, 1914. We offer
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and Reproduction Information: Information in NASD does not represent
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NASD Review: 04/2002
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