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Collapse strength, tensile strength, 13 3/8" API casing

Collapse strength, tensile strength, 13 3/8" API casing

Collapse strength, tensile strength, 13 3/8" API casing

(OP)
I would like to calculate the collapse strength and tensile strength of an API casing which has been perforated over 16% of it's surface as per the following:

API 13 3/8", K-55, 54.5 PPF, Range 3, BTC.  Perforated with 5/8" holes uniformly positioned across the length and circumference of the casing.  See attached drawing.

RE: Collapse strength, tensile strength, 13 3/8" API casing

nottoobright;
First off, tensile strength is a material property that will not change from loss of material.

Here is a tip, I consider use of ASME Boiler and Pressure Vessel Code, Section VIII, Div 1 for guidance and use one of the design rules for openings in a shell (HINT UG-53).

Second tip, the formula for determining minimum thickness requires information such as hole pitch and spacing. The thickness for the casing will be determined based on area loss.
 

RE: Collapse strength, tensile strength, 13 3/8" API casing

(OP)
metengr
thanks for your reply.  I have to try and keep it as simple as possible.  I've had the following advise from a German friend who has worked in the oil screen business and is now retired.  Unfortunately he's on a motorbike tour of Europe so his access to information is limited. Here's what he had to say:

Take API collapse value for equivalent   carbon steel casing from standard 5B/5CT. Reduce by 20% due to perforation of base pipe. Screen jacket will not be considered!
For tensile same applies. Take value from API list and reduce by 20%

Would you or anyone else have access to these values of collapse resistance and tensile strength for API seamless casings 13 3/8", 54.5 PPF in K/J-55 material?  I've got the 5B and 5CT but these values are not mentioned.

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