Pipe or tubing collapse pressure

[bgt]

Hi everyone,<br>
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I am an electrical engineer currently designing a downhole survey tool. This tool could be subjected to pressures of up to 12,000 psi. The o.d. of the tool will be 1 13/16&quot;. I need to find out how much room I have inside to place my electronics package. To find this out I need a formula to calculate the collapse pressure of tubing when subjected to pressure from the outside. Most of the information I have found deals with pipe pressure ratings when internally pressured. I assume a pipe can sustain much higher pressure when pressured from the outside than the inside. I will probably use 316 stainless for its' corrosion resistance, although this is still to be decided. <br>
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Thanx in advance for your help<br>
<br>
BGT<br>

 

[DenverEngineer]

A simple formula based on pressure would be misleading. You need to combine the collapse pressure with external pressures caused by interaction with the ground. To do this correctly I would need some additional information regarding the intended usage and rigs it would be attached to.<br>
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If you do not have such information and are in the concept stage you could use a formula to get the minimum required wall thickness. The actual tool will be thicker and probably be most economical if internal structural support rings were installed. I will get back with you later with this formula. Give me your e-mail if you want me to e-mail it to you.<br>
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