Aggregate Working Load Limit

Ok a bit embarrassing but I need a refresher from my flatbedders. I have just been hauling lumber locally for over a year now and the reg book is confusing me at the moment.

I have 3/8 grade 70 chains and Standard ratchet binders. Apparently rated at 6,600 lbs. I'm picking up a piece of cargo that is 27,000 lbs and has four tie down points. Are 4 direct tie down chains enough or can I only use 50 percent of the WLL of each chain?I remember that there is a simple way to calculate it. Can I just double the WLL of the chain? Can't remember If someone could respond with a simple breakdown of how they calculate and short explanation that would be great! Thanks.

And now I'm extra confused. So I get 50 percent of the anchor point too??

Nick, if you do a direct tie down you'll have 6,600 pounds WLL per chain. That's assuming your tie down point on the trailer and cargo are rated at that. You always calculate your WLL by the weakest link.

If you secure it at four points you'll have an aggregate WLL of 26,400 pounds. The math doesn't make it legal. You'd probably be able to deliver it safely, but it wouldn't turn out good if somebody wanted to check your securement. Can you throw a strap on it in addition to your chains? Or can you get a couple of extra chains and maybe do two direct tie downs on a couple of the anchor points on the cargo? Those two suggestions would work to remedy the issue.

Sorry, I just saw your request this morning.

In that photo example you showed us those are not examples of a "direct tie down." That is why they calculate 50% of the WLL of the device.

Actually I can't see the photo really well on my phone. I may be way off on that last comment.

Direct tie down ( from trailer to cargo or trailer through point on cargo and vac to same side of trailer) gives you 50% of WLL on item used. Indirect (from oneside of trailer of through or around cargo and to the other side of trailer) gives 100%. Whatever the weakes point between chain ratchet and anchor determines your actual WLL per securement device. Aggregate is the sum of all securement devices and must equal at least 50% of cargo weight. It must also stop movement in all 5 directions.

Brandon is correct. I got confused on those terms of "indirect and direct." Sorry about that, and thanks Brandon for jumping in here.

Nick, I apologize. I have gotten lax on these regs. On this dedicated account we are required by the customer to do things by a higher standard. I am so accustomed to the standards here that I forget the actual technicalities. Time for me to do a refresher myself.

Ok a bit embarrassing but I need a refresher from my flatbedders. I have just been hauling lumber locally for over a year now and the reg book is confusing me at the moment.

I have 3/8 grade 70 chains and Standard ratchet binders. Apparently rated at 6,600 lbs. I'm picking up a piece of cargo that is 27,000 lbs and has four tie down points. Are 4 direct tie down chains enough or can I only use 50 percent of the WLL of each chain?I remember that there is a simple way to calculate it. Can I just double the WLL of the chain? Can't remember If someone could respond with a simple breakdown of how they calculate and short explanation that would be great! Thanks.

Neek,

Sure hope you worked that load out...

Where've you BEEN ?!?!?

Some of us TT peeps would love nothing more to hear 'something' from ya.. HAPPY DAD'S DAY, too .. BTW!

~ Anne ~