Belly loading a sagging stretch trailer?

Discussion in 'Heavy Haul Trucking Forum' started by kylefitzy, Jul 21, 2019.

  1. kylefitzy

    kylefitzy Road Train Member

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    This thread is not about any one load in particular, but for general knowledge.

    I pull a lot of stretch rgns and double drops. Most of the time they are a fixed load loaded right in the middle of the trailer. They are fairly light so no real issue with sagging.

    I thinking about some of the odd ball loads that may come up. The long load that is not really self supporting. How do you counteract the sagging in the well? I’ve head of guys lifting the trailer and putting shims between the deck and the stretch beams. On the trailers I have pulled there is already a gap above the stretch beam so I don’t think that will work.

    I know we used to keep a few jo dogs around for the added 5th wheel height. That only works if you happen to be near one and I never am.
     
  2. If you can post pics of any example that may help also for new ppl
     
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  3. TripleSix

    TripleSix God of Roads

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    . A stretch trailer, even brand new, is going to flex like crazy. I would think that a non structural piece would have to almost certainly get damaged by the trailer flex. On a structural piece, you have to dunnage the ends of the load to prevent the trailer from slapping the load.
    The stretch trailers usually have an air adjustment setup on the rear where you could alter the ride height of the rear quite a bit.

    I haven’t seen too many non structural pieces ride on a fully stretched trailer. Like @peterbilt_2005 said, do you have any pictures?
     
  4. @TripleSix the only sag I've scene is to heavy for deck or very old deck that lost it's arc. I'm assuming this may be what the OP is possible thinking.
     
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  5. TripleSix

    TripleSix God of Roads

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    He said STRETCH. At full stretch, a brand spanking new trailer will sag if loaded heavy. But on your normal RGNs, if they’re worn, they will sag so much that they will drag on every bump.
     
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  6. Bad Monkey

    Bad Monkey Medium Load Member

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    I don't if its what you want but use a couple of ramps to support the load in the open area and it works pretty well. But they don't help with the sag though.
     

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  7. kylefitzy

    kylefitzy Road Train Member

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    No load
    this is the particular load I was referring to with the jo dog.
    Anything he could have done differently? Any way to shim a non modular trailer?
     
  8. Razororange

    Razororange Road Train Member

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    Not really. As soon as you start stretching the trailer the rating drops. The beams just aren't thick enough with enough overlap to support that kind of load all the way open.

    I don't think I'd agree to pull a load that looked like that myself. Maybe across town but not cross country.

    If the load can't help support the trailer then you really need to use a modular that can be shimmed properly.

    In your pictures the trailer is already bending negative. Every bump you hit makes it bounce even further down putting even more stress on the limited overlap between the inner and outer frame. Only a matter of time until that causes a failure.
     
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  9. Diesel Dave

    Diesel Dave Last Few of the OUTLAWS

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  10. Razororange

    Razororange Road Train Member

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    Works a bit different with a stretch flatbed and your nice solid load that isn't trying to bend itself in half.

    With a stretch flats loaded like you are the load is putting all the weight on the 2 ends over the king pin and the axles. I bet it would start bending if you put all your blocking in the middle between the KP and tridem. That block at the back is pushing down on the back and lifting the middle helping it stay flat.
     
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