Building a frame for an old diesel generator

[Legomad]

Hello all,

I found this forum just today and am completely stoked it's here, since I am a big fan of forums, especially ones related to engineering

To get to the point, I will be designing a frame to support an 8 tonne diesel motor and a 5 tonne alternator on the back of a truck, then later for display (this is an old old piece of machinery damaged a few years ago in a flood, now being moved to our museum for a glorious retirement).

I'm 1.5 years out of university and looking forward to doing the design, but I've never done anything like this before so I'm hoping you can give me a bit of inspiration for a design geometry.

The generator was designed so that it sat in a small pit, supported by two rails (above the sump) on either side with multiple bolt holes. If any of you have done or seen a frame that could support something like this, could you please direct me to a website that shows how it's done?

I think I'll be OK with spec'ing the type of channel steel to take the load, but anything you can do to help me visualise a good structure would be greatly appreciated.

Thanks very much and I hope that I can be of assistance to others on this site as well.

Legomad

 

[ishvaaag]

If people is going to walk under it you need to set your object at some height, and normally obstructions to pass won't be wanted, hence it calls for a rigid-joints 3D frame table setup. Loading for transport may include only the longitudinal beams plus some transverse members ensuring indeformability of the base. Then you may complete the thing where for display. Depending on the size, you may use a rectangular strip foundation, a single footing, or 2 footings with maybe some on-the ground tie or ties.

In the analysis you will account for vertical loads and lateral forces, including P-Delta since your structure is likely to be slender and laterally deformable. Inertial forces under earthquake can be very significant and will be accounted for, depending upon where you place the machine.

You may choose only a central support but this might diminish the ability to see details of the machine. In this case your tray setup will cantilever from its top.

If people is not going to go under it, using bracing will be cheaper, since delivering stiffer structures at lower cost.

You better use closed sections where people can wound themselves accidentally. In fact round columns would be ideal on this account, but is not the case for the connections.

 

[Legomad]

Thanks very much ishvaaag, the frame for this engine will only be about 600mm high, definitely not for people going under!