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Pipe Deflection

Pipe Deflection

Pipe Deflection

(OP)
I have a tube that is being forced against a fixed top face (see attached for details) and I am trying to calculate the perpendicular deflection when the force is applied.

I do not have a clue where to start, any pointers would be very helpful.

RE: Pipe Deflection

as for pointers,
check for allowable compression force, and euler buckling.

if the load is applied in the center of the pipe and you're within allowable (elastic) loads, there shouldn't be any "perpendicular deflection" on that end of the pipe, unless I'm understanding your question wrong.

RE: Pipe Deflection

I agree with kingnero,

Perpendicular [to the pipe axis] elastic deflection is possible in case of buckling or if the load isn't centered. In the latter case the tube undergoes both bending and compression.
Please note that buckling may also arise because the load is not properly centered or due to imperfection of the tube itself.
Anyway, I guess that you will design the tube in order to avoid buckling, so in absence of bending no perpendicular deflection is expected.

Hope it helps.

Stefano

RE: Pipe Deflection

theoretically zero, practically deflection would result from imperfections in ...
a) the straightness of the tube,
b) the cross-section of the tube,
c) the material properties of the tube,
d) the concentricity of the applied load,
e) the uniformity of the applied load,
f) the weather.

your stress is very low (if your dim'ns are inches, i get 150psi). euler is a start. maybe use modified column calcs to account for non-straight column, over a 1000" (?) the column is quite likely to have a wave, worst case might be a single sine wave, amplitude = allowable out-of-straight tolerance ? you could also account for the load being slightly eccentric.

RE: Pipe Deflection

RB1957 is correct, essentially zero. The loading keeps the wall stresses within the elastic limit of the material. But I would calculate the expansion in diameter of the pipe in response to axial shortening due to this load, in accordance to Poisson's Ratio.

You sound Canadian oilfield, using P110 casing and reference geometry in metric. The load was "120 ton" which I've taken as imperial in US tons, which is typical for the patch to be mixing units. Next time use load in deka-Newtons, daN, roughly an imperial ton. So I get virtually zero for vertical deflection and 0.099 mm for diametral expansion.

Attached is the solution, if my assumption on the units for loading is incorrect, you have the model to which to re-grind your solution.

Regards,
Cockroach

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