Horizontal vessel supports civil works

[KevinNZ]

What's the trick to getting supports and foundations built for large horizontal vessels built with tolerances to match the vessel saddles and bolt holes? The two supports can be some distance are part and a few mm out at one end can be big problem at the other end.

 

[BJI]

You have tolerance in the grouting of the base plates (and slide plates, if not cast in). 'Tolerance pockets' can be used on the cast in anchors, or templates can help to locate the anchors within tolerance.

 

[mk3223]

Typically, the bolt holes of sliding end saddle are slot holes with larger width to accommodate with the tolerances of the vessel fabrication and the foundation construction.

 

[r6155]

Any photo?

Regards

 

[KevinNZ]

We have moved on and convinced the vessel designer not to use bolts and slotted holes at the sliding end. We will weld side stops when the vessel is in place. Now we only have get the two supports level and not be too concerned with the alignment of the holes between the supports. Even the spacing between the supports can be 10s of mm out.

 

[r6155]

where was the inspector?

Regards

 

[jtseng123]

Not a problem without bolting and slot at the sliding end. Bolting and slot hole have just been used for decades that no one wants to change this common practice. Yes it does have disadvantage as you state.
Side stops are good enough. However, you will need to check wind and seismic load to make sure it will not tilt over without holddown bolting, you will also need to check bolting shear stress at fixed end.

 

[jtseng123]

And don't use stops if it is in severe seismic zone unless your stop come with a bar to hold down the saddle baseplate. When earthquake hits, it jumps, just like train, will derail.