If you go for various lab tests like metallography, hardness, tensile strength etc., you won't get much difference between samples heat treated as per NACE or ASME.
I have faced such situation and the non-conformity that I raised was closed based on such tests.
I was a quality assurance /...
Dear DustMan,
What I meant exactly were as follows:
1. There should not be a material diversity in your application, like you are using both CS and SS, which could lead to Galvanic Corrosion.
2. The corrosion behaviour of the product that would flow through the CS or SS application needs to be...
"All this for a localized thinning of the outer annular plate....."
YES as yours is a mounted tank.
The onus of this scenario lies on Civil Maintenance & Inspection Department as the vegetation issue took quite some time (maybe months) to cause such thinning all the while those guys were...
Always better to demonstrate the hardness in the PQR. If the hardness is off limit in the field joints, you may have to go for a fresh PQR in addition to cut and re-weld those joints.
The Gas Turbine (GTG) and the Heat Recovery Steam Generator (WHRU) are connected through duct. When WHRU fails, the gas turbine exhaust is diverted to the intermediate stack through diverter damper. During normal operation, the flue gas passes through the guillotine damper, then the WHRU and...
1. Is the corrosion external only?
2. Did you carry internal inspection of the tank after the thinning was noticed?
If the answer to 1 is yes, then find out the reason. Possible causes could be rain water accumulation, presence of acidous gases nearby, etc.
If the answer to 2 is no, then carry...
Send a sample to a metallurgical lab for proper material identification.
That is the ONLY option as it seems you do not have previous purchase orders / MTCs / other documents that could indicate the original material for the insulation rings.
Pneumatic test has been suggested due to subsequent drying issues for the pipe after hydotest. However, there are many techniques in vogue for drying of piping after hydrotest. Convince the client regarding the hazards of pneumatic test and furnish the procedures that you would perform to dry...
Why not directly buy the finished products from the market after approving MTCs?
What is the purpose of ordering the same from a forge shop? Is it that cheaper?
With 4" billet, they can make higher size elbows and flanges.
What is the corrosion rate?
Is the thickness (< 2 mm) since commissioning?
If you can manage with the above, better weld build up during total shutdown / complete turnaround.
