Re: regarding wall thick calculation

From: <stanley.chukwuma@exxonmobil.com>
Date: Mon Jul 23 2007 - 03:48:00 EDT

For pipe wall thickness calculation, The pressure to be used is governed by this factors (I stand corrected)

The operating Pressure or the maximum operating pressure the systems would accommodate.- This is used to determine the ANSI pressure class that the piping systems falls into and this is covered in ASME 16.5 see table F2 The pipe material - The pipe material determines the material of the flanges to be used and ASME 16.5 groups materials into different groups according to their PT values (eg. A105, A350 LF2, A216 WCB are in group 1.1 while A 352 Gr LCB in Group 1.3)
For Group 1.1 the WP is 2025 psig @ 200deg F while Group 1.3 is 1980psig @ 200degF
The value of P to be used in wall thickness calculation is also governed by the highest temperature that system can see ( refer to table F2 ASME 16.5)

The value of the working pressure obtained from the table F2 on ASME 16.5 w.r.t the design temperature is your DESIGN PRESSURE (again I stand corrected).

I have heard of 1.5operating pressure being the design pressure but I really don't know how that fits in? ( I do need some guidance on this) I know 1.5design pressure is your hydrotest pressure according to ASME 31.3

Best regards,

C. Stanley

Mechanical/Piping Engineer,
Design Engineering Services,

              ravi.kant@fluo
              r.com
              Sent by:                                                   To
              PipingDesign@y           PipingDesign@yahoogroups.com
              ahoogroups.com                                             cc

                                                                    Subject
              07/23/2007               Re: [PipingDesign] regarding wall
              05:00 AM                 thick calculation


              Please respond
                    to
              PipingDesign@y
              ahoogroups.com

For Pipe wall thickness calculation,
we start calculation with the operating pressure...

which is then multiplied by the factor to get Design Pressure. i.e.

Operating Pressure x 1.5 = Design Pressure.

and then, This Design Pressure is used as the ' P ' in the formula for the Wall thickness Calculation.

Regards,

Ravi

"Dhayanithi V" <pipingworld@gmail.com>
Sent by: PipingDesign@yahoogroups.com
07/22/2007 04:17 PM
Please respond to PipingDesign

To
PipingDesign@yahoogroups.com
cc

Subject
[PipingDesign] regarding wall thick calculation

for pipe wall thickness calculation, which pressure we have to take into account like *operating*, *design*,*test* pressure

[Non-text portions of this message have been removed]

---

The information transmitted is intended only for the person or entity to which it is addressed and may contain proprietary, business-confidential and/or privileged material. If you are not the intended recipient of this message you are hereby notified that any use, review, retransmission, dissemination, distribution, reproduction or any action taken in reliance upon this message is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

Any views expressed in this message are those of the individual sender and may not necessarily reflect the views of the company.

---

[Non-text portions of this message have been removed]
Received on Mon Jul 23 03:48:00 2007