QUESTION
Can any one tell me what 5L stands for in the API 5L standard?
REPLIES
gpcoker
Yes; “5” for Committee 5 OCTG (oil country tubular goods) and L for line pipe. Formerly there was 5L with grade A and B; and a second spec ,5LX ,containing X42 and higher strengths. These were combined into a new 5L. No user used Grade A but the mills insisted it stay in the spec.
Other Com. 5 specs; 5D- drill pipe, 5CT- Casing and Tubing.
SOURCE
https://www.eng-tips.com/viewthread.cfm?qid=289416
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