Force of a 3-6 Ton Trailer on a hook to a bus?
Force of a 3-6 Ton Trailer on a hook to a bus?
(OP)
Hello everyone
I am working out the apropiate size of the end transverse beam in a coach/bus which has a 3 to6 Ton trail tied to a hook in that beam. Does anybody know the appropiate horizontal/vertical force magnitude that I should take into account for my calculations? I consider braking (1 g) as the maximum effort. Is that right or do I miss some other extreme situation?
Thank you everybody
PedroRB
I am working out the apropiate size of the end transverse beam in a coach/bus which has a 3 to6 Ton trail tied to a hook in that beam. Does anybody know the appropiate horizontal/vertical force magnitude that I should take into account for my calculations? I consider braking (1 g) as the maximum effort. Is that right or do I miss some other extreme situation?
Thank you everybody
PedroRB





RE: Force of a 3-6 Ton Trailer on a hook to a bus?
Cheers
Greg Locock
RE: Force of a 3-6 Ton Trailer on a hook to a bus?
The following equations are from SAE standard J684, regarding testing of the receiver tube, which ties into your beam.
1. V = .47R + 480
L = .47R + 480
2. L = -(.23R + 1530)
V = .15R
3. L = .23R + 1530
V = .15R
4. T = .20R + 500
Where V is the vertical force, positive in the downward direction; L is the horizontal force, positive in the forward direction towards the cab; T is the transverse force; R is the hitch rating, in your case 12,000#.
Remember, these are the loads at the the ball. You will get a moment from the vertical force multiplied by the distance from the ball to the beam.
Good luck,
hauptmann
RE: Force of a 3-6 Ton Trailer on a hook to a bus?
Just a pair of questions, Hauptmann, about the equations: are the forces expressed in Pounds or Newtons? What´s the hitch ratio? Is the SAE Standard J684 available in internet for free?
PedroRB
RE: Force of a 3-6 Ton Trailer on a hook to a bus?
All the forces are in pounds. The hitch will be rated at a weight representing the maximum allowable towable weight, 12,000 lb for your case. I do not know of any site with this standard available. We have the three volume set of SAE standards which covers just about everything you might have questions about. You can buy it online at sae.org for about $50.