Binding Tractor to Trailer

[Reb954]

My understanding and practice is to apply the 45 degree angle from front to back of the trailer, not from the trailer deck up. The reasoning is to keep or minimize the chance the load will move sideways or forward or back which will help in keeping everything top side up. If the truck, trailer and load are turning over, I doubt I will be too concerned about whether the load stays attached to the trailer or not.

 

[3gunr]

I have been hauling multiple different tractors 140 miles one way to my farm for 20 yrs. iI put 2 chains up front and one in the rear on the drawbar. never had an issue , If i have an implement on the rear i use several straps on it.

 

[Tractor Seabee]

Tractor Seebee, this response is not directed at you so please don't take offense.

When I read the "trust the science" comment, my mind equated it to the "trust me" saying we all hear and avoid anyone saying it. The politicians, through this pandemic, keep using "trust the science" as a way of telling the rest of us to shut up and do as we are told, kind of like "trust me". The actual scientists are saying very little due to knowing they haven't developed enough "science" to trust.

Politician Mantra "If the facts do not support the theory, change the facts".

Ron

 

[Tractor Seabee]

From an engineering standpoint:
"An equilateral triangle is structurally the most sound for obvious reasons. Equal angles and vectors naturally resist gravitational and lateral forces equally in all directions. This is true in theory and practice if one doesn't consider any other variables. Isosceles triangles always are weakest along its longest side and near its smallest or sharpest angle."

So I guess the flatter the angle in relation to the trailer bed the weaker it is. The fore and aft angle was not part of the original discussion but equally important. Again 45 degree is strongest for movement for and aft. That is why a flatter truss roof has to have larger members than a steeper truss roof. Engineers need to weigh in on this and educate all us I am a practical construction gut not an engineer.

Ron

 

[aczlan]

From an engineering standpoint:
"An equilateral triangle is structurally the most sound for obvious reasons. Equal angles and vectors naturally resist gravitational and lateral forces equally in all directions. This is true in theory and practice if one doesn't consider any other variables. Isosceles triangles always are weakest along its longest side and near its smallest or sharpest angle."

So I guess the flatter the angle in relation to the trailer bed the weaker it is. The fore and aft angle was not part of the original discussion but equally important. Again 45 degree is strongest for movement for and aft. That is why a flatter truss roof has to have larger members than a steeper truss roof. Engineers need to weigh in on this and educate all us I am a practical construction gut not an engineer.

Ron

Here are a couple examples:

A tie down that is too flat and doesn't cross enough:

Very strong at preventing movement from front to back, weak at preventing moment up and down or side to side.


45 degrees up and down, left/right and front to back:

Roughly equally strong in all directions.

Cross tie:

This lets you overcome the lack of room to tie things down by tying down to the opposite side.

Aaron Z

 

[bindian]

How do you gat a 45 degree angle with the drawbar 12" or less from the trailer bed?

Ron

Buy a bigger tractor.

Interesting facts......................all my equipment, the Mahindra tractor loader backhoe, the Caterpillar E70 excavator and the Lull 644D-34 telehandler all have tie down points at the lowest places on the frame. Three different machine industries, three different designed loads. Three different weights..........14,100, 15,500, and 20,160 pounds. Three (or more) engineers have their name on those hard points. What's in common............ All three have tie down mounts low.

I do know I can bind my tractor down where you can see the tires squatting. It's big enough and beefy enough to do this. Just get a longer cheater pipe. I pride myself in chaining all my loads tight enough that when I check the load, no adjustment it needed. But I still have to check.
hugs, Brandi

 

[Reb954]

From an engineering standpoint:
"An equilateral triangle is structurally the most sound for obvious reasons. Equal angles and vectors naturally resist gravitational and lateral forces equally in all directions. This is true in theory and practice if one doesn't consider any other variables. Isosceles triangles always are weakest along its longest side and near its smallest or sharpest angle."

So I guess the flatter the angle in relation to the trailer bed the weaker it is. The fore and aft angle was not part of the original discussion but equally important. Again 45 degree is strongest for movement for and aft. That is why a flatter truss roof has to have larger members than a steeper truss roof. Engineers need to weigh in on this and educate all us I am a practical construction gut not an engineer.

Ron

Actually the strongest is 0 degrees but that would require 3 chains and binders for each corner (up and down, side to side and forward and back) of the load which isn't practical or necessary. 45 degrees of a sufficient sized chain holds the load front to back and side to side sufficiently. Any rubber tire load is going to bounce some so the idea is to keep it in the same place on the trailer while it is bouncing.

There are cases where tying a rubber tire load down with a vertical or close to vertical chain will actually break the chain. Picture a rubber tired loader with the big tires. There is no way you will keep it from bouncing but with a vertical chain, every time the loader bounces down it throws slack in the chain but when it comes back up it has a lot of force and momentum that can snap the chain. As Brandi stated, equipment that has tie downs has them relatively low so the chain is pivoting and has less chance of getting slack in it.

 

[Chrisb009]

I also have worked in logistics, loading aircraft and other items while in the VANG. This design would be reliant on two grade hardened fasteners attached to the rear most housing of the tractor itself. I feel this design is reasonable to contain a tractor weighing under 7k (including implements in the 7k figure). If the rear housing cannot support the load via two fasteners then it痴 poorly casted or inferior materials were used to manufacture the item.

-Chris

 

[aczlan]

I also have worked in logistics, loading aircraft and other items while in the VANG. This design would be reliant on two grade hardened fasteners attached to the rear most housing of the tractor itself. I feel this design is reasonable to contain a tractor weighing under 7k (including implements in the 7k figure). If the rear housing cannot support the load via two fasteners then it痴 poorly casted or inferior materials were used to manufacture the item.

-Chris

Such a load will largely be a tensile load, if it's a 3/8" fine thread grade 5 bolt on each side, the breaking strength is 7450#, thus the WLL would be 2483# per bolt.
I wouldn't trust that for a 7000# tractor.
The hitch on a tractor will generally have at least 4 bolts around the PTO housing for vertical loads, then 4 more bolts into the underside of the axle housing to handle horizontal loads.

Aaron Z

 

[Chrisb009]

Such a load will largely be a tensile load, if it's a 3/8" fine thread grade 5 bolt on each side, the breaking strength is 7450#, thus the WLL would be 2483# per bolt.
I wouldn't trust that for a 7000# tractor.
The hitch on a tractor will generally have at least 4 bolts around the PTO housing for vertical loads, then 4 more bolts into the underside of the axle housing to handle horizontal loads.

Aaron Z

Thing is the tractor doesn’t weigh 7k...closer to 4K without attachments. Would you trust it now?

-Chris