Fit to be Tied

| November 01, 2001

Cargo securement has been a problem since the days when wooden ships carried most cargo (after all, we still call transportation “shipping”). Securing cargo was critical on ships not only because whatever got loose in a storm could hurt the crew, but also because shifting weight could make the ship unstable, and even cause it to sink.

Smart truckers know that the same principle applies to them: Proper loading and lashing of cargo makes for a more stable vehicle, and a safer and easier ride not just for the other traffic, but for truckers themselves.

Cargo securement is a lot like braking: The name of the game is friction, says Jim Feddern, motor carrier enforcement manager at the Ohio State Highway Patrol and chair of the Commercial Vehicle Safety Alliance vehicle committee. Summing up the whole science of cargo securement, he observes, “It’s not about tying cargo to the trailer. It’s about maximizing the friction between the cargo and the trailer. That’s why blocking and bracing are so effective, and why using rubber mats can also be a great aid to cargo safety.”

Know your cargo
Feddern believes when it comes to loading cargo, “The main thing is to know the weight and other characteristics of the cargo.” Is it slippery like steel or dressed lumber, or will it develop friction like concrete pipe? And there’s a big difference between a 40,000-pound load and something that weighs 20,000 pounds.

Start out with a clean deck. Then, know the size and working load limit of each tie-down.

Larry Strawhorn, vice president of engineering at the American Trucking Associations, points out that tie-down materials are rated using a safety factor of three. In other words, if a chain breaks under 3,000 pounds of tension, its working load limit is 1,000 pounds. Both experts explain that you simply find out the total weight of what you’re securing, then make sure you install enough tie-downs. You have enough when the sum of all their working load limit ratings equals one half the cargo’s weight (that’s the applicable rule in the Federal Motor Carrier Safety Regs). Doing the math this way will be a big help in operating safely and passing roadside inspections.

Then, if possible, use blocking or bracing to block movement. “Use sturdy timbers, not just a piece of a 2×4,” says Feddern. Ideally, any block will have a beveled edge so the cargo will have a wider surface to rest against and be less likely to crush the wood and work its way loose.

Strawhorn says one critical issue is “getting the right torque on the reel hubs. Most truckers believe that if a 200-pound man pulling on a 6-foot bar is good, then a 300-pound man on an 8-foot bar is better. It’s not true! Obviously, if you’re bending protectors and links, you’re going much too far.”

It’s normally not a good idea to use a cheater of any kind, or substitute another pry bar – the one provided by the winch or tensioner maker is designed to help you apply the right amount of torque. Then, says Strawhorn, “You have to calibrate yourself.” That’s not easy because most suppliers don’t seem to give torque ratings for tightening their straps or chain. He suggests you contact a dealer or distributor who has a relationship with the manufacturer for training materials, then study them.

This cargo is secured properly, with straps and chains attached to built-in winches and attachment points, and protective materials also in use.

Avoiding classic mistakes
“Gravity is not a load securement device,” says Feddern. Roadside inspectors see plenty of trucks loaded with dense materials like concrete block piled neatly, but otherwise unsecured. Just because it’s heavy doesn’t mean it’ll stay in place. Tie everything down, no matter how heavy it is.

Truckers also get into trouble because they make a good-faith effort to tie down the cargo, but don’t do the job scientifically and end up a bit short. Know the cargo weight and ratings of your tie-downs, calculate carefully on paper or with a calculator, and then use enough tie-downs to satisfy the rule.

Strawhorn says it’s important to use the right grade of chain. Grade 8 is hard and brittle, and it can chip. Bigger may not necessarily be better, so he doesn’t recommend Grade 10. By far the best is Grade 7, which is labeled “transport” for good reason. While manufacturers’ type codes differ, if there’s a 7 in the code, that means it’s Grade 7 chain.

Fit to be Tied

| November 01, 2001

Cargo securement has been a problem since the days when wooden ships carried most cargo (after all, we still call transportation “shipping”). Securing cargo was critical on ships not only because whatever got loose in a storm could hurt the crew, but also because shifting weight could make the ship unstable, and even cause it to sink.

Smart truckers know that the same principle applies to them: Proper loading and lashing of cargo makes for a more stable vehicle, and a safer and easier ride not just for the other traffic, but for truckers themselves.

Cargo securement is a lot like braking: The name of the game is friction, says Jim Feddern, motor carrier enforcement manager at the Ohio State Highway Patrol and chair of the Commercial Vehicle Safety Alliance vehicle committee. Summing up the whole science of cargo securement, he observes, “It’s not about tying cargo to the trailer. It’s about maximizing the friction between the cargo and the trailer. That’s why blocking and bracing are so effective, and why using rubber mats can also be a great aid to cargo safety.”

Know your cargo
Feddern believes when it comes to loading cargo, “The main thing is to know the weight and other characteristics of the cargo.” Is it slippery like steel or dressed lumber, or will it develop friction like concrete pipe? And there’s a big difference between a 40,000-pound load and something that weighs 20,000 pounds.

Start out with a clean deck. Then, know the size and working load limit of each tie-down.

Larry Strawhorn, vice president of engineering at the American Trucking Associations, points out that tie-down materials are rated using a safety factor of three. In other words, if a chain breaks under 3,000 pounds of tension, its working load limit is 1,000 pounds. Both experts explain that you simply find out the total weight of what you’re securing, then make sure you install enough tie-downs. You have enough when the sum of all their working load limit ratings equals one half the cargo’s weight (that’s the applicable rule in the Federal Motor Carrier Safety Regs). Doing the math this way will be a big help in operating safely and passing roadside inspections.

Then, if possible, use blocking or bracing to block movement. “Use sturdy timbers, not just a piece of a 2×4,” says Feddern. Ideally, any block will have a beveled edge so the cargo will have a wider surface to rest against and be less likely to crush the wood and work its way loose.

Strawhorn says one critical issue is “getting the right torque on the reel hubs. Most truckers believe that if a 200-pound man pulling on a 6-foot bar is good, then a 300-pound man on an 8-foot bar is better. It’s not true! Obviously, if you’re bending protectors and links, you’re going much too far.”

It’s normally not a good idea to use a cheater of any kind, or substitute another pry bar – the one provided by the winch or tensioner maker is designed to help you apply the right amount of torque. Then, says Strawhorn, “You have to calibrate yourself.” That’s not easy because most suppliers don’t seem to give torque ratings for tightening their straps or chain. He suggests you contact a dealer or distributor who has a relationship with the manufacturer for training materials, then study them.

This cargo is secured properly, with straps and chains attached to built-in winches and attachment points, and protective materials also in use.

Avoiding classic mistakes
“Gravity is not a load securement device,” says Feddern. Roadside inspectors see plenty of trucks loaded with dense materials like concrete block piled neatly, but otherwise unsecured. Just because it’s heavy doesn’t mean it’ll stay in place. Tie everything down, no matter how heavy it is.

Truckers also get into trouble because they make a good-faith effort to tie down the cargo, but don’t do the job scientifically and end up a bit short. Know the cargo weight and ratings of your tie-downs, calculate carefully on paper or with a calculator, and then use enough tie-downs to satisfy the rule.

Strawhorn says it’s important to use the right grade of chain. Grade 8 is hard and brittle, and it can chip. Bigger may not necessarily be better, so he doesn’t recommend Grade 10. By far the best is Grade 7, which is labeled “transport” for good reason. While manufacturers’ type codes differ, if there’s a 7 in the code, that means it’s Grade 7 chain.

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