Weight Distribution across a flatbed trailer?

Learning how to properly distribute the weight on your trailer comes with experience and repetition. You need to know what your empty weight is full of fuel and I would say ½ tank of fuel. You also need to know your axle weights while empty too.

In my early days I would get loaded and go find a scale. I made a notebook with what each load weighed and it's position on my deck. This was my way of keeping track of everything and learning my equipment. After a couple of months and multiple loads I was able to load my trailer and get the weight distributed properly so I wasn't always having to reposition my load. It's not always easy to do because each load is going to be different and have different characteristics.

In your example load with the four coils I would load my 53' step deck like thos...

Bottom deck is 42' long

5K coil 3' behind the step
5' space
10K coil
5' space
5K coil
5' space
10K coil

 

Are you running a spread or regular tamdem? Whats your empty axle weight?

 

Center of trailer for loading is half the distance from the kingpin to the center of the trailer axles. You want to scale your wagon unloaded but full of fuel. Since you have multiple items, utilize the 1/4, 1/2, and 3/4 spots of the trailer, according to the kingpin and the trailer tandems and not the side marker. Should be fairly easy to figure out how to load them and get both the trailer axles and drive axles even.

Luck in battle.

 

More often than not I just let the yard/loader dude do his thing. Weights are generally spread great, but I can adjust them if need be...

They ask, and I tell them. Very rarely have I ever needed to make adjustments by adjusting hitch pins...

 

For one thing, you also have to take height and size of the coils into account also. For instance, in reference to regulations, you need to put a smaller, lighter coil at the front of the trailer, which ends up techically being a header for all intents and purposes..then you need to consider the actual weights. With a spread at back, it get the heavier coil(s) closer to it, than the front, but always being mindful of the balance and structural integrity of the trailer.

In your example, the first one would have both 5,000 lb coils in the front, and the 10,000 lb coils to the back separated by a little space closer to that spread. If you have a sliding tandem, that's going to be more trial and error, because you'll need to try and have your axles set before loading because once loaded, they may not move at all from the weight.
The same principles would apply with your second scenario. The smaller/lighter always goes to the front, heavier to the back.

 

First off, finding the center of your trailer like TripleSix mentioned (king pin to center of spread) is pointless. If you put 50k lbs there then the truck and trailer get 25k. Using imaginary weights as I don’t know your specifics, it sounds like a good idea until you realize you already have 15k on your truck axles already from weight of the truck and trailer. While your trailer has let’s say 7k lbs already. So in this scenario putting 50k in the center of your trailer is as retarded as one of my dogs. You need to find the center where weight is evenly distributed between trucj and trailer then go about 6” behind that so you don’t risk being overweight as you’re allowed 6k lbs more on a spread axle trailer.

in your first example I would do a 5k, the two 10ks, then the other 5k so the weight is balanced and I can use just 1 tarp to cover them. If it was no tarp I would do 4’-6’ space between them (2-3 stand pockets for example) as it’s better for the trailer to spread out weight.

 

I will get the popcorn started.
You get the beer.

 

This is why I like a 48' spread. Center on the turn signal and it'll scale. If it doesn't it never would, just find a good way to get it there.

 

As a disclaimer, I'm a door slammer, but Six is on point. You are as well, but you're applying Six's logic to get to the ultimate answer. Knowing where the center point is allows a driver to know where the balance point is. If a truck with a fixed tandem spread scales out at 12,000/15,000/7,000 empty with center point X and you want to put 50K on the trailer then a driver knows that they're already overweight. So let's drop cargo weight to 46k. If the freight is loaded on the center point 23k is going on the drives, 23k on the trailer. That won't work. The driver needs to shift 4,000 lbs to the rear, which by my math is 3 feet back from the center point.

Knowing where the center point is not the ultimate answer as to how the freight needs to be loaded, but it's the starting point to understand weight distribution. One shipper said "I'm going to load you XXX", and that would probably have worked but my tandems would have been all the way up with a 1k differential between drives and tandems. I made him stretch me out to the back doors, ran at 42.5' KPRA with balanced weights. Two weeks ago I was loaded with 43K but the load only hit the 40' mark internally. I was skeptical, but put the tandems to the front and ran to the trucks stop to scale out - I was 36 and change on the drives. Back to the shipper, they reworked but I was still at the 42' mark and I told them it wouldn't work. We kibbitzed and they reworked me again, spreading me out to the 50' mark - scaled out at 34k on the drives with the tandems all the way forward. I knew where my center point was, which allowed me to avoid having to go back a second time.