wall thickness of pipes

[jdanielods]

Dear Sirs:

I just have a brief question in regard to the physical properties of pipes.

Is it possible to obtain the wall thickness of pipes by only knowing the piping class (for instance B3) and the ASME pressure class. I have not got information in regard to the pipe schedule. I just know the nominal diameter, and the pipe class and I need to get the wall thickness of some pipes.

Regards
Daniel

 

[GregLamberson]

Daniel

You will also need the design factor (.72, .6, .5), the design pressure, operating temperature, corrosion allowance (if any), joint factor, and pipe grade (SMYS).

Greg Lamberson
Consultant - Upstream Energy
Website:

http://www.oil-gas-consulting.com

 

[DSB123]

Daniel,
If you know the pressure class (e.g. 300 LB) then you could "over-design" and assume the highest pressure rating for that class at the highest temperature and assume a significant corrosion allowance and then determine the thicknesses for a range of materials. However I would ask for a project line list and determine the pipe thicknesses based on the information stated by GregLamberson above to achieve economic pipe schedules.

 

[BigInch]

Daniel,

Don't get the impression that pipe design is based only on internal pressure stress and maximum material temperature rating.

BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com

 

[STYMIEDPIPER]

GLamberson was directing you towards a minimum wall thickness calculation provided that you obtained the criteria that he had identified. Upon determining the required minimum wall thickness based on your applicable criteria than you can determine the probable schedule of the pipe as referred by DBS

 

[dcasto]

jdanielods, it would be a huge leap in faith that the original designer or party that wrote the spec had a complete match of flange class and pipewall. I've sen lots of plants have 6" sch 40 grade B pipe and class 600 flanges. The pipe won't get to 1480 psi.

 

[GregLamberson]

Depends on the code. For B31.8 or B31.4, 6" sched 40, Grade B with a design factor of .6 is good up to 1,775 psi and up to 2,130 at .72.

Greg Lamberson
Consultant - Upstream Energy
Website:

http://www.oil-gas-consulting.com

 

[dcasto]

another leap of faith by me, I refered to plant piping.

 

[BigInch]

Nothing in the plant piping code? (B31.3) requires pipe walls to match pressure ratings of flanges or valves.

BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com

 

[dcasto]

Exactly my point.........

 

[odem]

How about a UT meter?