Pipes, Flanges...need some advices...thanks

[riccardoamato]

Good morning to everyone.

I'm new in this world, i start working now in the off-shore (i'm a civil engineer) than i'm trying to learn quickly.

Talking about sealine: if i have a sealine made by pipes API 5L X52 which flanges (ANSI 900? ANSI1500?) i will choose and why? And if the pipes are X65?

I know that many of you will laugh so much reading my question, but thanks to all of them who will answer.

THANKS...waiting for some answer.

[colinfoong]

Simplistic answer, first find out the pipeline's design pressure, and pipe wall thickness. Select the flange to match the pipeline design pressure and wall thickness. Grade X65 requires thinner wall thickness for the same design pressure. Google for 'Barlow equation' for more detail. Refer to ASME B16.5 for example table 2-1.1 for flanges pressure rating and service temperature using group 1.1 material. ANSI 900 flange is good for 139.8 barg up to 100 deg C. ANSI 1500 is good for 233barg for same service temperature.

[riccardoamato]

thank you so much!!! very helpfully!