I am conducting a basic research project on corrosion and thickness readings for piping and have come across this 12.5% tolerance placed within piping calculations specifications for seamless piping. I understand the reasoning behind the tolerance to account more manufacturing error but was inquiring about the science or study supporting this number. Is there a study or statistical reference for where this 12.5% tolerance came from and if so can you direct me? The reason for this question is to dive into the regulations, or lack there of, surrounding the testing of pipe for uniform thickness. We have not come across a set standard requiring a specific number of readings taken for a length of pipe or its thickness but rather that it is based on client request for piping mills. I see this as a possible flaw in the piping industry and would like to hear your take on the subject.
Sincerely
Daniel
Asset Integrity Analyst
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