Duplex stainless steel U-factor. What is it?
Duplex stainless steel U-factor. What is it?
(OP)
I have recently reviewed a Shell specification supplied to us by our customer. In it, it states that Duplex stainless steel castings to ASTM A890 Grade 4A shall have a minimum U-factor of 25, and the following formula is applied:
U = -43.64 + (4.76xSi%) + (2.65xCr%) + (3.44xMo%)
Does anybody know what the U-factor is, and why it is being used in this case?
Thanks
U = -43.64 + (4.76xSi%) + (2.65xCr%) + (3.44xMo%)
Does anybody know what the U-factor is, and why it is being used in this case?
Thanks





RE: Duplex stainless steel U-factor. What is it?
RE: Duplex stainless steel U-factor. What is it?
RE: Duplex stainless steel U-factor. What is it?
You asked Shell and they have not responded since February? Sounds like your customer dropped the ball because I believe Shell would have responded rather quickly.
Have your customer go back and apply pressure to Shell for the clarification to their specification. It is their (Shell's) specification and they should provide you with a clarification to an item. This is common. Your attempt to find the answer back door is risky.
RE: Duplex stainless steel U-factor. What is it?
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: Duplex stainless steel U-factor. What is it?
Completely disagree with this statement. Taking exception or asking for clarification to an item in a detailed bid specification could mean that you either cannot meet it or you do not understand what it means (as is this case). One can always ask for clarification of an item, and if they do not provide the clarification, it probably means the organization does not know why it was there in the first place!
RE: Duplex stainless steel U-factor. What is it?
In this instance our customer is technically switched on, and has been buying duplex from us for a number of years. He has also gone to Shell to ask the same question, and he has had the same (lack of) response. This is why I ask the question here, in the hope that someone might have the answer, even though Metengr thinks it may be a "risky" route to take.
RE: Duplex stainless steel U-factor. What is it?
So what? If the organisation asking for it doesn't understand why, it's not the supplier's problem. The supplier can meet the requirement with no issue - carry on.
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: Duplex stainless steel U-factor. What is it?
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: Duplex stainless steel U-factor. What is it?
RE: Duplex stainless steel U-factor. What is it?