MANDATORY HARDNESS TEST AFTER PWHT

[MACARIO PALOLA]

Sirs,

Is it mandatory to perform hardness test after pwht of P91?

Do we have supporting code?

Thank you for your reply.

Mac

[Vishwas Keskar Welding Manager WELDING]

It is depending on Design Construction code / Client specification

Normally ASME  SEC I , piping,  equipment does not call  for Hardness test .

As a practice , random hardness checks are  carried out to ensure effective PWHT.

Maximum Hardness reading shall not exceed 275 - 280 BHN .

Hardness checking procedure shall outline Testing Method, type of equipment, Operator 

API 938 , does specify Hardness of 250 BHN maximum .

Regards

Vishwas - IWE

International Welding Engineer