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ANSI 300 #.... meaning

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IPO25

Mechanical
Oct 7, 2010
4
Hello everyone,
I have attached a page out of a fluid thermal systems book and I am confused on what the "ANSI Designation 300#, 400#..." in the table is referring to. The table basically gives pipeline cost per foot for the various grades.
The only thing that I can think of is that the "300#, 400#..." is referring to flange classes. It is confusing thought that the table says it is pipeline cost per foot. So are there codes that for pipes that are also classified in the 300 #, 400 #.... designations? Is there something I am missing here?
In the paragraph above the it says to refer Annex A, ASME B16.47, which is in the Large Diameter Steel Flanges standards. Any input will help. Thanks in advance.
 
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Some organizations choose to rate their piping specifications according to the flange rather than according to process conditions.

The pipe isn't stenciled "B16.5 CL300" but every component in the spec meets or exceed B16.5 CL300.

- Steve Perry
This post is designed to provide accurate and authoritative information in regard to the subject matter covered. It is offered with the understanding that the author is not engaged in rendering engineering or other professional service. If you need help, get help, and PAY FOR IT.
 
IPO25,
Regardless of what it means (and I think that it refers to ANSI flange rating and equivalent piping between), it is pure nonsense.

First, the table is in 1980 dollars, if you bring that forward to 2010 at the CPI (or the IPI) you get around a factor of 3. I looked at 10-inch ANSI 300 and got $9000 per inch mile, so bringing it forward to 2010 I get a number around $27,000/inch-mile. In 1990 I was using $50,000/inch-mile, and today the number is closer to $70,000/inch-mile for steel pipe with adders and subtractors for project length and client's exceptional requirements.

Second, these numbers would be very specific to a particular purchaser, a particular engineer, and a particular contractor. For example, if I build a pipeline for Chevron, they have a set of safety and operational requirements that are quite expensive to implement. The same job for a small independent oil company might cost 70% of a Chevron job or even less. If I hire a contractor that has a training program for each piece of equipment and can show me certification papers, they will cost more than if I hire a contractor that doesn't have a training program and is a bit lax about checking citizenship status, sometimes a lot more. A company requirement that you have to use hydrovac equipment to expose line crossings can add significant costs to a job.

Worldwide rules of thumb from 1980 are simply not worth the electrons it took to display them.

David
 
That clears it up a little for me. I had a feeling they were referring to the flange class/equivalent for the pipe they were using. Since they wouldn't necessarily label the pipes by B16.6 Classes, do they go by ANSI/ASME B31 to determine the pipe size for the rated pressure they are trying to be equivalent to? I must say that the these standards can get confusing if you are just starting to learn them. Thanks in advance.
 
I wanted to add, I was looking at American Ductile Iron Pipe
ANSI/AWWA C150/A21.50, and they also use the Pressure Class designations. But they actually seem to refer to the pipe, with varying OD and not the flange. I know tubes are measured by their outside diameter, so does that classify it in the tube category even though it is intended to carry potable water?
 
Perhaps ductile iron would explain your mention of Class 400. Most of the standards mentioned as ANSI standards in this thread are actually issued by ASME. AWWA is a different organization.

The maximum pressure suitable for flange classes within ASME B16.5 vary for the flange material and temperature. Thus if someone selects the maximum B16.5 pressure at temperature for A 105 steel then a stainless steel flange would require a higher flange class.

AWWA C207 requirements differ from the ASME standards and apply to flanges "intended for use with steel pipe, fittings, or appurtenances meeting the requirements of ANSUAWA C200, ANSUAWA C208, ASTMA134, ASTM A139, or other equivalent standards. It is intended that flanges be attached by welding in accordance with Sec. 4.3 ... ."
 
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