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anyone straightened a rgn that was oveyloaded?

baexcavating

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Feb 10, 2013
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baraboo, wi
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Work like a rented mule to make ends meet
Long story made short... Let a guy use my Rodgers RGN and he overloaded it to the point that the I beam frame rails are bowed down an inch instead of being arched up. I need to know if there is a good way to straighten them, or if I should cut them out and replace them.
 

Delmer

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Jan 3, 2013
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I've never done it so take it for what it's worth...

At one time beams like that were bent by shrinking the metal with a torch, heating a small section to red hot, and when it cools it shrinks bending the beam. I could find the pics and rough instructions if you wanted to consider it. "Internet Expertise" only.
 

td25c

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Feb 14, 2009
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indiana
I have hammered out my share of bent & sprung steel over the years . My motto is if man can bend it , man can also straiten it .:)

Simple approach is usually best ....... I mean just reverse procedure .

Flip the trailer over & crib up as needed & crawl up on & over it with some heavy iron . Add reinforcement as needed .

Picture would help .
 

clintm

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I have wondered about this also but I do know that some of the trailer beams are fabricated with the arch welded in them. at least it's a quality name brand I would contact them to see what they recommend to re arch it I am sure that it's not the first one that it's happen to by the way what size trailer is it and what did they load on it please keep us informed on the outcome
 

baexcavating

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Work like a rented mule to make ends meet
Trailer repair companies "Re-arch" trailers I know, might want to consult the experts?

I'm use to doing all my repairs myself, and would like to learn how to do this. I plan on calling a shop that does this tomorrow to ask the best way to do it. I like to check with as many sources as possible before attempting a major project for the first time
 

baexcavating

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baraboo, wi
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Work like a rented mule to make ends meet
I have wondered about this also but I do know that some of the trailer beams are fabricated with the arch welded in them. at least it's a quality name brand I would contact them to see what they recommend to re arch it I am sure that it's not the first one that it's happen to by the way what size trailer is it and what did they load on it please keep us informed on the outcome

He put 100k on a 35 ton trailer that's 22 years old.
 

clintm

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thanks I have put about 80 on mine but was careful and took it easy went about 5 miles with no problems
 

chevota84

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Apr 12, 2011
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189
Location
Prineville OR
That's not to bad .

Think positive bro........... You now have a 50 ton rated 22 year old RGN .

Maybe 49tn, seems 50 was too much. There used to be a place around here that re arched flatbed by anchoring the front and rear and pulling on the center with a crane.
 

td25c

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indiana
Yeah chevota84 , something along that line . Simple mechanical fix .

Could also use two pieces of equipment , Load one on the tail end and crawl another up on front load ramp with cribbing in the center of the trailer beams . I still think you would need to add some reinforcement to keep the arch in it .

Really 1 inch sag in say 20 feet aint to bad . One thing I've noticed is once they bow like that it just seems to stay there & not get any worse .

Buddy of mine has a mid 1970's 35 ton Vulcan single drop low bed . His has about 1-1/2 " bow in the middle of the bed when empty . Bows a little more when loaded but not much . Been like that for 20 years .
 

digger doug

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NW Pennsylvania
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Rodgers Brothers trailers is nearby me, and thay had a open house tour for the 100 year celebration.

I vaugually remember the trip, but didn't see any cambering operation per se.

The beams are flat plate welded up, and IIRC they placed them in a fixture, and that
had the pre-camber in it.

Old timer (long gone) had a Rodgers trailer and wanted to overload it one time, so asked the factory.

They said the tires are the "fuse" and would blow first, but only if you drove real slow.
They said they designed them this way.
 

td25c

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Yeah digger doug . Rodgers has forgotten more about building Lowboy trailers then most companies today know .:yup

Damn tough old trailers !
 

Fastdirt

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GA
He needs to buy you a 20 year old 35t rgn. You give him the problem trailer. That's the only way to solve it. What kind of trailer was it? Probably find one for $15,000. Cannot believe somebody would do that to you. Blows my mind.
 

oceanobob

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oceano california
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The Lincoln Manual of Arc Welding discusses this in pretty good detail. The instructions tremendously helped us by showing us to not overheat (not necessary) and to use a garden sprayer mist to cool it off. The basic idea is: let's say you have a block of steel made by your good friend on his mill and it is exactly one point o inch in all directions. If you put it in a decent vise and snug it, then heat it and let it cool, likely it will fall from the vise and then when you measure it - it won't be the same dimensions in all directions anymore. The principle of restraint and unrestrained is taught to welders....when to clamp, when to not clamp, what direction to clamp, sequence of welds etc. Similar block heated up without the vise will return to the same dimensions.
This is because the "temperature to strength curve" for steels that are typically used for equipment and buildings tends to weaken noticeably when heated and not necessarily that hot. Also this is exactly why steel frame buildings have fire protection and why our shops made of metal "so called it wont burn" quickly fall into a big heap when there is a contents fire.
Given this theory, the next trick is to figure out the shape of the heating pattern and also we definitely can suggest in getting a nice rosebud as opposed to the cutting torch (w/o lance LOL) for the heating. Gotta know your acetylene flows and very likely need to manifold the acetylene when using a decent rosebud; bigger gas cylinders have higher allowable flows. Check with your welding gas supplier.
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The job typically plods along and once you get setup to keep from being worried about the usual stuff like burning up wires or yourself, and you have your measuring tools or string or whatever, it is kind of interesting to be involved to plod along and see it all happen. Kind of reminds me like painting or mowing a lawn or troweling a concrete slab.
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If the steel is alloyed, then this procedure may need to be watched and the heating temperature absolutely limited to around 600 or 700F degrees - this can be checked with a temp stick which is like a wax crayon that melts at a certain temperature and is inexpensive (out two faves are ones at around 600 / 700 and a 350F for aluminum). Heating to red hot is not necessary - this I can tell you, which is what we did when we were experimenting without the knowledge. Structural steels with low carbon like A36 and A992 don't have enough carbon to make them respond to temperatures that would change the grain on an alloy steel or higher carbon steel.... for example, once carbon is increased like 1040/1050 or certainly a 4130 crmo with it's alloy components, then excessive temps which certainly include welding temps will affect the properties permanently and immensely. We generally figure if the steel spec allows welding, then some miscellaneous heating to less than 700F will be quite OK for us to use the flame. We have had to submit this procedure and its basis in writing [as some folks immediately prohibit flame heating] to get an overriding decision from The Authority Having Jurisdiction.
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A wedge shape is a common heat zone for wide flanges. We have cambered and uncambered many things using this. Tube steel and pipe we arent quite as competent - gotta refine the technique.
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I would imagine a combination of the heat and some restraint would make the job proceed in short order, to the point where the gathering and prep and cleanup would take longer than the heating. And I guess I should mention that sprayer concept from the Lincoln book seems to help greatly: I figure if the steel absorbs too much heat energy overall, then the differential is lessened. All "sages" we learned from did not mention the sprayer but we were told by quite a few "ya dont need to git er real hot if ya know what yer doin" and of course they didn't supply many details LOL.
Steel does have what some call memory which is from the internal stresses from the grain structure and the (hot and cold) forming process at the rolling mill; some beams obey readily but others are more stubborn...and the as delivered so called natural camber is not necessarily the hint that you can count on.

Hope I got the idea across; you will have to take a look at your job to see how this applies and if things like braces or clips could interfere with this etc.
 

JBlackwell

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Jun 1, 2009
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Daingerfield, Texas
Yes fabricated "I" beams can be re-arched. Depends if the trailer is worth spending the money on or not. 22 year old 35ton trailer in my opinion is worth maybe $20-$22k in good condition with out me seeing pictures. Rearching the deck will cost somewhere around $3,500-$5,000 depending on beam size from my experience. I have had it done before, but has been a few years. Biggest thing is who is the closest person to you with experience to do that for you? After you figure up the expense of running back and forth 2 times to the welding shop you need to ask yourself is it worth you keeping the trailer or not?

Justin
 

Scrub Puller

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Gladstone Queensland Australia
Yair . . .

There used to be an old feller had a reputation for building tough gear back in the seventies. Worked out of a tin shed in a little country town, him and his missus and an occasional offsider knocked out half a dozen a year . . . if you wanted one you got in the queue.

He never messed with heat shrinking cambers on the main beams. They were cut every few feet, jacked up in the middle on a jig and rewelded with a piece of (say) 3/4" flat bar x whatever the flange width of the beam or channel was welded on it's flat on outside of the bottom flange . . . he did use the heat and quench caper on the side rails but bemoaned using all that expensive oxy.

I have built a few bridges and walkways using that method, seems positive and simple.

Cheers.
 
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