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Fantastic ideas for a Fantastic World, I make the illogical logical.They put me in cars,they put me in yer tv.They put me in stereos and those little radios you stick in your ears.They even put me in watches, they have teeny gremlins for your watches
A53 permits both welded and seamless. As was noted, API 5L is referenced in A53; not in A106.
A106 allows only seamless (not welded); A106 anticipates High Temperature Service for end use. Therefore, A106 must comply with ASTM A520, A53 does not.
milo
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People say between two opposed opinions the truth lies in the middle. Not at all! Between them lies the problem, what is unseeable,eternally active life, contemplated in repose. Goethe