Working Pressure 2

[sowhatso]

Dear all,

I need to know the working pressure for welded steel pipe of standard ASTM A53 Grade B , Type E , and of SCHEDULE 20 for Pipe sizes of 8” , 10” , 12” , and 16 “ ?? our specifications call for pipes to be rated for 600 psi working pressure , so we need to be sure that the above mentioned standard of SCHEDULE 20 will give 600 psi working pressure (This schedule is proposed by the supplier) ???

ALL the datasheets that I found during my search did not show that the above mentioned standard will provide 600 psi WP.

See attached the following file that show the working pressure less than 600psi:

• datasheets No. 1 and NO.2 from two separate engineering websites that show the working pressure less than 600psi
• The datasheet from the piping handbook
• The datasheets for Wheatland Tube Company that show the actual working pressure – after multiplying with the safety factor (not the theoretical WP) for the 8” steel pipe.

I know that working pressure will depend on the standard select for calculation as ASME B31 Standards, the safety factor, and the chosen temperature. The temperature that we have will not exceed the ambient temperature 50 C deg (will not exceed 400 F), and the service is for drinking water networks.

The factory hydrostatic pressure test exceed the working pressure, but for sizes of 12” and 16” it is 820 psi, and I feel this number is close to the working pressure,

We called the manufacturer to send the pressure/temperature chart; however, I still need your advice in this issue...

Thanks in advance for all you inputs.

Merry Christmas and happy New Year ….

 

[CRG]

What piping code do you intend to use for the design?
Do you have access to the relevant piping code?
Why are you asking suppliers & folks here to tell you what schedule pipe you need instead of taking the responsibility for the calculations yourself?
Are you an engineer?
How have you determined your corrosion allowance?

 

[GregLamberson]

sowhatso

Is this a case where you have the pipe laying around and are trying to see if it will work for this application? In any case, as CRG points out, determine the code and do the calcs based on that and see if it fits.

Also, not sure if I understand your note correctly, but the safety factor is not determined by the service of the pipe, but is spelled out in each code depending on where the pipe is being routed, i.e. heavily populated areas, rural, etc.

It sounds like you have the mill certs on the pipe, again, next step is to make the pressure calcs based on whatever code you are going to use and it will either work or not.

Greg Lamberson, BS, MBA
Consultant - Upstream Energy
Website:

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

 

[sowhatso]

CRG and Creg :

I don't have any access to pipe code . is there are any equation that I can follow to calculate the working pressure for the steel pipe of standard ASTM A53 Gr.B , Type E , and the pipe will be used for drinking water transmission line ?? any equation that you recommend and I can use to calculate the working pressure ?

Thanks in advance ...

 

[racookpe1978]

I am very troubled by the large number of widely spread questions on a very large number of design topics you have needed to raise on this single buried water pipe project: selection of pump impeller material, depth of burial when you hit granite rock, pump sizing calc's, welding/bolting connections on underground pipies, pipe material choices and selections, flow resistance, pipe pressure ratings and on and on.

From a top down view - and I am admittedly not in your country nor am I your customer - but something appears very, very wrong with the level of supervision and design guidelines you (your company ?) and your customer have been given. It certainly appears that you have not been given the resourses (the civil, mechanical, piping engineer help) you need to actually design this project if this many fundemental issues have come up.

If a single village or a single small town cannot afford detailed design and civil planning, I understand. All of us have to "redneck engineer" around problems to solve problems in our personal houses and proejcts. And, rural or stretched budgets are limited: this may be the only way to get drinking water to your customers (neighbors). But jury-rigging substitutes and scraping by with reading and know ing the Codes- the reasons behind the Codes - isn't safe in the long term. I can run an extension cord across the street and get power to my neighbor's house as well; but that is not a solution to get him power for a week, a month, or a year.

But you need at least several days of "real engineering" from a qualified engineer (or two or three) to get this pipeline safely delivered. Learning from web sources, or trying to integrate many different engineering disciplines while you try learn all of the details of each discipline cannot deliver your pipeline safely.

Step back and think about your planning budget. Though I know you've been thinking about nothing but this project since about May.

Robert

 

[BigInch]

sowhatso,

When will you realize that pipeline design is a little more than getting the maximum pressure from the manufacturer? There are other additive stresses that must be considered. A 600 psi pipeline design, even with only water inside, is not safe to play around with.

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[Naif1981]

sowhatso,
i advise U to start with calculation for this problem and tell us what u got.

Do not trust the supplier, do u have an engineering dept.?