Dump Trailer

[fiddler kelly]

Patrick G,

If I set that up for a ram to dump it what size ram would I need and are there certain guidlines for calualating the size of ram you would need.

My plan was to use this behind my tractor with the backhoe attacted and using the bucket on the backhoe to lift and dump the trailor , by the way I know I ahve to cut the back out of the trailor for the gravol to fall. out.

 

[Mith]

Iplayfarmer, nice project! I'm looking forward to seeing it done.
I looked in as I am thinking about making something similar, for a similar size tractor.

One thing though, I think you might need to reinforce the mounts for your hydraulic cylinder, particularly the one on your bed. Looks to me like its going to twist off.
If you are dumping a 1000lb load, due to the angle of the ram, you could easily have several thousand pounds of force on that point.
A few triangular gussets should do the job.

 

[fiddler kelly]

Have made some more progress today ,all the parts for the hinging of the dump to chassie and making sure it is high enough so gravel and such willl come out easy,the pieces with the holes in them are going to make up the hinge and the holes are going to have pipe going through them with another pipe inside to act
as a pin. If I put the axel just to the back of the load with more weight in front of axle it should be able to be tipped with little effort ,that is where the backhoe will just lift it , saves on having to get hydraulics for it.

I will be putting steel plate on both sides of each piece of square tubing which the hinges are welded onto so as to give support.I also plan on overlapping flatbar from the axel up over the join where the uprights sit on the axel on the front and back to give extra strength.

After that it is only to finalize where the center piece of the hinge system attaches to the anglre iron on the bottom of the trailor for proper weight distribution.

I attached a couple of pictures of the 100 Gallon oil tank one I made. I dump this one manually due to the way it is balnced. Great little rig for getting loads in tight places. Holds about 50 gallons of gravel. I should have rotated that last pic with the one tire on .

 

[Iplayfarmer]

Thanks to all for the interest and advice. Fiddler Kelly, your project looks pretty good. It's going to handle a lot of weight.

I have been working on this a little here and a little there. I'm taking my time making the brackets into which the tailgate pins are going to fit, but progress is slow. Summer happens.

I think you might need to reinforce the mounts for your hydraulic cylinder, particularly the one on your bed. Looks to me like its going to twist off.

After I get all of the parts and pieces fabricated, I'm planning to break it back down into several component parts for prep and paint. When I have it broken down, I plan to add some structural support to a few places. I need to adjust the lower hydraulic mount about 1/16 inch, and I'm putting triangle gussets around both hydraulic mounts. I'm welding some angles in place on the bed frame and putting "trusses" in throughout the subframe to add rigidity. I may try to add some additional metal around the tongue to give it more strength, and I'm going to put angles into the bed sides. I'll seal weld some of the joints that I can't really get to with everything in place.

Then I'll prep and paint. Or pay someone else to prep and paint.

 

[Iplayfarmer]

If I set that up for a ram to dump it what size ram would I need and are there certain guidlines for calculating the size of ram you would need.

I'll make an attempt at answering this question.

You need to know four things...
1) the upward force needed to dump the load.
2) the rise of the ram (the difference in height between the top of the ram and the bottom of the ram)
3) the length of the ram measured from pin to pin.
4) the hydraulic pressure of the system that you are using to power the ram.

I start by figuring the force needed to dump the load is equal to the weight of the load itself. This is a rough guess since the weight in front of the ram attachment point is different from the weight behind it and both are altogether different from the weight behind the hinge point of the dump bed. But, it's the rough guess number that I have started with.

The needed force of ram is calculated by multiplying the actual length of the ram as measured from pin to pin times the force needed to dump the load divided by the rise.

If you are dumping a 2000 pound load with a 24 inch ram with a 6 inch rise, your force needed is 24 X 2000 divided by 6 = 8,000 pounds of force.

The cross-sectional area of a ram that will produce 8,000 pounds of force is calculated by dividing the needed force by the system pressure. If you have a 1500 psi system, 8,000/1500 = 5.33 square inches.

To calculate the ram size, divide the cross sectional area by 3.14159 (pi) and then take the square root of the result. Multiply the answer by two to get the ram diameter. 5.33/3.14159 = 1.69 The square root of 1.69 is 1.3; 1.3 X 2 = 2.6 inches.

In this scenario you'd either need a three inch ram (since they don't make 2.6 inch rams) or you'd need more pressure or a bigger rise to make a 2 inch ram work.

 

[fiddler kelly]

These are the braces I was talking about. I was talking to a machinist today and he told me I should use 1/8 welding rods instead of 3/32 for better penetration where the hinghing is so thick. Good thing I only have it spot welded.

 

[Iplayfarmer]

These are the braces I was talking about. I was talking to a machinist today and he told me I should use 1/8 welding rods instead of 3/32 for better penetration where the hinghing is so thick. Good thing I only have it spot welded.

Those braces will provide a good amount of strength. You might need the thicker rod to fill in some of the gaps.

That's where I have the hardest time welding...when the pieces don't fit perfectly.

 

[Iplayfarmer]

I finally got some time to make some progress on the dump trailer. I've fabricated the brackets for the tailgate and tacked them in place. I've posted a few pictures of the brackets below.

The top bracket has two positions for the pin. In the photo "Tailgate in Top" notice that the top pin is in the top slot of the upper bracket. The bottom pin is secured in the bottom bracket. In this position the tailgate does not swing. Lifting the tailgate a short way will allow the top pin to release, but the bottom pin stays engaged. This allows the tailgate to swing down like a pickup truck tailgate.

In the picture "Tailgate in Bottom" the top pin is in the lower slot. The bottom of the tailgate will swing freely as shown in the picture "Tailgate Swings".

It may not be the most sophisticated engineering, but I think it will meet my needs.

Let the constructive criticism begin...

 

[patrick_g]

Patrick G, If I set that up for a ram to dump it what size ram would I need and are there certain guidlines for calualating the size of ram you would need.

My plan was to use this behind my tractor with the backhoe attacted and using the bucket on the backhoe to lift and dump the trailor , by the way I know I ahve to cut the back out of the trailor for the gravol to fall. out.

Sorry, I was a bit late seeing your request but IPLAYFARMER seems to have covered the topic. I am not a well experienced hydraulics guy so I have to drop back to basic physics and work the problem like it was the first time it had ever been done. It works and you don't go too far wrong but it can be amusing for an expert onlooker. I also refer to this as my brute force and awkwardness method.

I would start with a sketch showing the side view of the rig. Then consider the lever arms and pivot points (assuming an even distribution of weight in the box). The hardest part requiring the greatest force is at the start of a dump to begin lifting the box. I do like to overbuild a tad (or more) to be on the safe side. Once the box starts to lift adequately the weight will begin to shift, easing the effort required. Also as the box tilts the lift force required is reduced even if the load doesn't shift.

If the tilt angle of the box is zero when not lifted (horizontal) and 90 degrees when lifted until straight up the lift force anywhere between horizontal to vertical is figured by multiplying the cosine of the tilt angle times the horizontal value (max value.) When straight up essentially ZERO lift is required and when horizontal max lift force is required. (cosine of 0 degrees is 1.0, cosine of 90 degrees is 0.0)


If you pivot the box a distance from the dumping end the overhanging weight aft of the pivot will help counterbalance the rest of the load and make it easier to dump. The more you offset the pivot the higher the bottom of the box has to be above the ground when in the lowered position so you can't go to an extreme and try to balance the load so that only a few lbs need to be exerted to rotate the box unless you don't mind the ground clearance needing to be a little over 1/2 the length of the box.

The minimum lift force for a box hinged at the rear extreme end and lifted at the front end (with evenly distributed load) is 1/2 of the total weight of the box and contents plus a little extra to begin the lift (1/2 just balances but doesn't lift.)

Along the lines of IPLAYFARMER's example... weight of lift divided by system pressure equals ram area.

It is good to be able to raise the box farther than the minimum that sheds dry gravel (angle of repose for dry gravel) because you may unload while your nose is pointed down slope and the material may be sticky and need to go essentially vertical with the box to dump it.

Hope these additional thoughts help.

Best of luck and POST PIX.

Pat

 

[Densleigh]

Jut to back track a little. I see you have made a slide up / down tail gate
assembly.

You might find that you have some difficulty raising / lowering this with any reasonable load in trailer as the load will work up against the tailgate even whilst it is flat and obviously not tipped up.

Commercial units have a lever clamp external so thta there is no lifting of tail gate required. many alos have just a projecting stub with apin down through end which can be pulled out / knocked out to allow tailgate to open.

Good luck with it.