API 5CT K55 normalized - marking

[alanisphoenix]

Hello,
i'm studying API 5CT K55 pipes for coulpling stocks, and i have a doubt about marking.

table C.48 On the heat treatment is written Z and N&T.
I suppose N&T is normalizad and tempering, but what about Z? it is Normalized? i can not found the meaning of Z anywhere on the standard.
At point3.3 Abbrevation : N = normalized, and Z is not mention.

what i have to paint on pipes K55 normalized?

thank you

 

[JStephen]

Surprisingly, I found a copy of that standard online. Not one I use. Eighth Edition, 2005, so maybe outdated.

But in Section A.4.4 SR9.4 Marking, I find:
"All coupling blanks meeting the requirements of A.4 (SR9) shall be marked as specified in Table C.68 or E.68
or Table C.81 or E.81."

Then in Table C.81, "Z" is the "Mark or Symbol" that is shown for J55, K55 or M65 normalized, while Q is used for J55, K55 or M65 quenched and tempered.

In Section 4.2, definitions, "N&T" is Normalized and Tempered.

I don't see that used in Table C.48, tho, so maybe a different version.