[tracer]

http://i205.photobucket.com/albums/b...210101024a.jpg

This is a pic of the grader I moved from Montreal QC to Stoney Creek, ON (close to Buffalo, NY and US border). I used 2 chains in the front, 2 in the middle, and 3 in the back. I know most guys use only 4 chains for something like this (plus one more chain over the blade, right?) but I wanted to comply with the DOT requirement of 0.4 G for the forward movement and 0.5 g for the rearward movement. Which means the chains in the back of the machine must be able to withstand roughly 40% of its weight. And to add to confusion, there's an "aggregate work load limit" requirement, where all chain WLL together must be equal to at least 50% of the machine weight BUT - get this - only chains that go from one side of the trailer to the other side through or over the load are awarded the full WLL (4,700 lbs in my case). If a chain's one end is hooked to the trailer and the other - to the machine, for the purpose of the "aggregate work load" requirement it only counts as 50% or 2,350 lbs with my 4,700 lb WLL chains.

Could they have made it more complicated?

So, I put a bunch of chains on the rear of the grader (especially since it had wheels) and made sure chains were going from one side of the trailer to the other - through the 'eyes' on the frame of the machine. If you looked at the grader from the back, it looked like I had 20 chains in there

So, ow do you calculate how many chains to put on a machine like this? Weight: 33,600 lbs. Length: 28 ft. Height: close to 10 ft.[ATTACH=CONFIG]626[/ATTACH]

[rank]

I remember before you got your step you were talking about pulling a grader. Looks like you found one. Below is a cut and paste from the FMCSA rule book.

Minimum Working Load Limit for Cargo Securement Devices and Systems
The aggregate working load limit of any securement system used to secure an article or group of articles against movement must be at least one-half the weight of the article or group of articles. The aggregate working load limit is the sum of: One-half the working load limit of each tiedown that goes from an anchor point on the vehicle to an attachment point on an article of cargo; and The working load limit for each tiedown that goes from an anchor point on the vehicle, through, over or around the cargo and then attaches to another anchor point on the vehicle.

[tracer]

Originally Posted by rank

I remember before you got your step you were talking about pulling a grader. Looks like you found one. Below is a cut and paste from the FMCSA rule book.

Minimum Working Load Limit for Cargo Securement Devices and Systems
The aggregate working load limit of any securement system used to secure an article or group of articles against movement must be at least one-half the weight of the article or group of articles. The aggregate working load limit is the sum of: One-half the working load limit of each tiedown that goes from an anchor point on the vehicle to an attachment point on an article of cargo; and The working load limit for each tiedown that goes from an anchor point on the vehicle, through, over or around the cargo and then attaches to another anchor point on the vehicle.

Didn't I say the same in my post? So, for the machine weighing 33,600 lbs you'd need 4 chains, provided they go from one side of the trailer to the other via a hole/eyelet on the grader. But with only 4 chains you'll be in violation of Rule #2: 0.4 G restraint in the rear from the forward movement.

[rank]

Originally Posted by tracer

Didn't I say the same in my post? So, for the machine weighing 33,600 lbs you'd need 4 chains, provided they go from one side of the trailer to the other via a hole/eyelet on the grader. But with only 4 chains you'll be in violation of Rule #2: 0.4 G restraint in the rear from the forward movement.

I guess you did. I really only had time to skim it. Depends on how long your chains are. If they are long enough to go from trailer through the ties down lugs and back to trailer yes, you can get away with 4 chains.

If the chains are shorter and you need to run them from tie down lugs to the trailer, you would need 7 chains.

As far as the g force requirements are concerned, I can tell you the DOT guys don't go into it that deep. We've moved literally hundreds of pieces of equipment and we've been ticketed once. The driver drove the 10,000 lb tractor fwd until it touched the drop of the step deck, then set the parking brake and secured it with one chain across the hitch at the rear of the tractor. DOT cop pulled him over on the 401 in Whitby and fined him.

[tracer]

Originally Posted by rank

Depends on how long your chains are. If they are long enough to go from trailer through the ties down lugs and back to trailer yes, you can get away with 4 chains. If the chains are shorter and you need to run them from tie down lugs to the trailer, you would need 7 chains.

As far as the g force requirements are concerned, I can tell you the DOT guys don't go into it that deep. We've moved literally hundreds of pieces of equipment and we've been ticketed once. The driver drove the 10,000 lb tractor fwd until it touched the drop of the step deck, then set the parking brake and secured it with one chain across the hitch at the rear of the tractor. DOT cop pulled him over on the 401 in Whitby and fined him.

So as long as I have enough chains to cover 50% of the weight and these chains go from one side of the trailer THROUGH or OVER the machine and terminate at the other side of the trailer, I should be okay. I guess it wouldn't hurt to block the wheels somehow too... Plus add one more chain to secure the blade, if there's one.

[allan5oh]

It's not a matter of how many chains, it's a matter of do you have chains that are properly sized.

(a)(2) Working Load Limit. Tiedown assemblies (including chains, wire rope, steel strapping, synthetic webbing, and cordage) and other attachment or fastening devices used to secure articles of cargo to, or in, commercial motor vehicles must be designed, installed, and maintained to ensure that the forces acting on the devices or systems do not exceed the working load limit for the devices under the following conditions, applied separately:

(a)(2)(i) 0.435 g deceleration in the forward direction;

(a)(2)(ii) 0.5 g acceleration in the rearward direction; and

(a)(2)(iii) 0.25 g acceleration in a lateral direction.

(d) Aggregate working load limit for tiedowns. The aggregate working load limit of tiedowns used to secure an article or group of articles against movement must be at least one-half times the weight of the article or group of articles. The aggregate working load limit is the sum of:

(d)(1) One-half the working load limit of each tiedown that goes from an anchor point on the vehicle to an anchor point on an article of cargo;

(d)(2) One-half the working load limit of each tiedown that is attached to an anchor point on the vehicle, passes through, over, or around the article of cargo, and is then attached to an anchor point on the same side of the vehicle.

(d)(3) The working load limit for each tiedown that goes from an anchor point on the vehicle, through, over, or around the article of cargo, and then attaches to another anchor point on the other side of the vehicle.

With any heavy wheeled vehicle you should only use direct tiedowns, and these tiedown WLL's must add up to the cargo weight. When you use indirect tiedowns, you actually get double the WLL. The way they wrote the law is silly. They should've said the aggregate has to equal the weight of the cargo, you get 1X for direct tiedowns, but 2X for indirect (passing through) instead of this half baloney. For a quick example a 40,000 lb load can be secured by 4 5,000 WLL straps. As long as it's not over 30 feet(not prevented from forward movement) or 40 feet (prevented from forward movement).

So to calculate your grader:

Weight of 33,600
Four tiedowns using direct method

33,600 / 4 = 8400 WLL

Would be legal if you used four tiedowns of 7/16" or 1/2" chain. Or double each corner with 3/8" chain. Of course your securement points and binders have to be rated above this as well. In Canada you cannot use 5/16 chain for any heavy wheeled vehicle, the WLL must be above 5000 lbs for any tiedown(5/16 is rated for only 4700 lbs). That's why I say it's the size of the chain that matters, not how many.

On my trailer the tiedowns are only rated for 6600 lbs, even though it isn't stated on the trailer. So I'd need to use 8 3/8" chains minimum for that grader.

[allan5oh]

Rank do you ever use the indirect tiedown method with heavy wheeled/tracked vehicles? I don't think I've ever seen that. All the RGN stuff we do it's always 4 big chains one at each corner using direct method.

[allan5oh]

Have at it tracer:

USA:

Part 393.100: Which types of commercial motor vehicles are subject to the cargo securement standards of this subpart, and what general requirements apply? - Federal Motor Carrier Safety Administration

393.100 through 393.136

Canada:

http://www.ccmta.ca/english/committe...2010_Final.pdf

[rank]

Originally Posted by allan5oh

Rank do you ever use the indirect tiedown method with heavy wheeled/tracked vehicles? I don't think I've ever seen that. All the RGN stuff we do it's always 4 big chains one at each corner using direct method.

Not often, but I have. Mostly I use that method when I don't have enough shorter chains to make it legal so I'll hook the other end to a different point and voila! My chain just magically doubled in strength. Or sometimes I'll do it if I'm nearing the end of the chaining and I don't feel like lugging another chain out LOL. Usually tho, my chains are too short to use that pass through method.

From reading his post (properly, the 2nd time) I gather Tracer has 5/16" chain.

[allan5oh]

Originally Posted by rank

Mostly I use that method when I don't have enough shorter chains to make it legal so I'll hook the other end to a different point and voila! My chain just magically doubled in strength.

I've often wondered why don't guys do the X at the back, but with just one chain. Go from passenger side on the trailer to drivers side hook on the cargo, over to the passenger side hook on cargo, back to the drivers side of the trailer. That way you could get away with just 2 chains. But you may not satisfy the x amount of tiedowns every x feet. Like this:

________
\      /
 \    /
  \  / 
   \/
   /\
  /  \ 
 /    \
/      \

Originally Posted by rank

From reading his post (properly, the 2nd time) I gather Tracer has 5/16" chain.

Then he's not legal in Canada regardless of how many he has.

I need some 3/8 chain as well.