Whether hauling equipment across a job site or across town, it must be properly tied down to a trailer.
Federal Motor Carrier Safety Administration Rule 393.106 is very specific about how to determine the aggregate working load limits for tie downs.
The Federal Motor Carrier Regulations' aggregate working load limit (WLL) uses equipment weight to identify the number of tie downs needed, as well as the tie downs’ capacity. The basic requirement is that tie downs must have a combined strength equal to at least 50 percent of the load being secured.
The rule requires that the aggregate working load limit is the sum of one-half the working load limit of each tie down that goes from an anchor point on the vehicle to an attachment point on the cargo.
Know the load rating of the trailer and the weight of the equipment that is being moved. The load rating can be found on the trailer identification plate or in the operator's manual. Equipment weight is obtained by referring to the owner's manual.
Use the information to ensure your load is under the legal load limit, which is 80,000 pounds in most states. Heavier loads, as well as those that are physically oversized (over-dimensional loads), require special trailers and permits.
Note that overloading a trailer can cause tire damage, and premature axle and bearing failure. It can also seriously affect handling, braking and acceleration. State and local regulations can be more restrictive than federal rules, so make sure you know the regulations for all the areas where you are hauling a load.
For example, if hauling a 20,000-pound backhoe, the chains must support a minimum of 10,000 pounds. A 3/8-inch grade 70 chain has a rated capacity of 6,600 pounds. Because this is divided by two according to the load limit calculation, four 3/8-inch chains are needed to properly secure the machine. If hauling a 40,000-pound excavator, more chains would be needed, or a larger half-inch chain would need to be used to tie down the equipment.
The best tie down angle is 45 degrees, which enables the chain to perform to its maximum designed working load.
To prevent damage to the equipment, pay attention to securement points on the machine. Also, double check the chain lengths after attaching to make sure the chains are not rubbing against hydraulic hoses. Refer to the equipment manual for manufacturer-recommended securement points.
Chains wear out over time and should be inspected prior to each use. Remove from service any with cracked, stretched or fatigued links. Also make sure any tie-down points, binders, hooks and clevis pins meet capacity regulations.
In summary, here are DOT’s recommendations:
Less than 10,000 lbs. – Use the four-corner tie down approach. Only two tie downs are required, however the four tie downs addresses the lateral movement issue.
Over 10,000 lbs. – use the four corner tie down approach. Add additional direct tie downs to drive axles as first option for adding working load limit. This provides extra protection for forward movement. As a second option, use indirect tie downs.
For articulated vehicles – use the four-corner tie down approach and secure articulation point either by indirect or direct approach.
The working load limits listed in the tables are to be used when the tie down material is not marked by the manufacturer with the working load limit. Welded steel chain which is not marked or labeled to enable identification of its grade or working load limit shall be considered to have a working load limit equal to that for grade 3 or 30 proof coil chain.
Neff Rental drivers are trained to properly load, unload and haul equipment. Oftentimes, they add extra chains to their loads to ensure that the equipment is properly tied down. While this takes longer to load and unload, the extra precaution ensures that the load arrives and leaves your job site safely. For information about Neff Rental, visit www.NeffRental.com, of call 888-709-NEFF.
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