Max Allowable Working Pressure for Welded & Npt Piping
Max Allowable Working Pressure for Welded & Npt Piping
(OP)
I would like to find a full updated chart for the maximum
allowable working pressure for welded and threaded carbon
steel pipe (all sizes & schedules) with corrosion factors from 0 CA to 1/4" CA
allowable working pressure for welded and threaded carbon
steel pipe (all sizes & schedules) with corrosion factors from 0 CA to 1/4" CA





RE: Max Allowable Working Pressure for Welded & Npt Piping
Regards,
Mike
6" SCHEDULE 10 ASTM A53 GRADE B TYPE E (ERW) PIPE
P = (2St) / D
P = PRESSURE (PSIG)
S = STRESS (FOR A53 GRADE B - 35Ksi)
t = NOMINAL WALL THICKNESS (INCHES)
D = OUTSIDE DIAMETER (INCHES)
(2*35,000) = 70,000
70,000 * .134 = 9,380
9,380 / 6.625 = 1,415
P = 1,415
'S' REDUCED BY A DESIGN FACTOR OF .72 WILL PRODUCE THEORETICAL MAXIMUM ALLOWABLE OPERATING PRESSURE (MAOP)
(2)(35,000*.72) = 50,400
50,400 * .134 = 6,753
6,753 / 6.625 = 1,019
P = 1,019
APPLY A JOINT EFFICIENCY FACTOR OF .85 FOR ERW PIPE, P = 866 PSIG
(MILL HYDROSTATIC TESTING IS PERFORMED AT 850 PSIG)
RE: Max Allowable Working Pressure for Welded & Npt Piping
I take issue with the above calculation.... ASME B31.1 or B31.3 should be the governing code for your operations and in both of these codes, the allowable stress is decreased as the operating temperature of the line increases. (see paragraph 104)
What you really have to do is to develop an organized set of pipe specifications (sometimes called line specifications) for each kind of fluid service. In each spec, piping, flanges, valves and gaskets are selected as per maximum combinations of temperature and pressure. ANSI B16.9 pipe fleanges typicall limit the service pressure for most systems....
Hope that this helps...... good luck !!! MJC
RE: Max Allowable Working Pressure for Welded & Npt Piping
I believe flanges are B16.5
Mike
RE: Max Allowable Working Pressure for Welded & Npt Piping
Tim S.
RE: Max Allowable Working Pressure for Welded & Npt Piping
PAN
RE: Max Allowable Working Pressure for Welded & Npt Piping
I had to locate this book on a used book website. At this time I cannot remember which one it was. It was a Canadian company.
RE: Max Allowable Working Pressure for Welded & Npt Piping
These rating are based on leakage as well as pressure contament, leakage typically being the controling factor.
RE: Max Allowable Working Pressure for Welded & Npt Piping
for Piping Engineer
Program
PipingOffice (full suite) Single User - I.D.
Capability
Pipingoffice is a set of Microsoft Excel-97 compatible spreadsheets for performing various piping engineering calculations. Following are included: Pipe Allowable Pressure per ASME B31.3; Pipe Allowable Pressure per ASME B31.1; Pipe Branch Reinforcement per ASME B31.3; Pipe Branch Reinforcement per ASME B31.1; Steam Safety Valve Reaction Effects per ASME B31.1 Appendix II; Pipe Mitered Elbow Allowable Pressure per ASME B31.3; Piping Properties; Pipe Support Span, Shoe Bearing, Jacketed Pipe Weight; Pipe Theoretical External Collapse Pressure; Pipe Allowable Pressure per ASME B31.3 Chapter IX High Pressure; Extruded Outlet Pipe Branch Allowable Pressure per ASME B31.3; Piping Line Blinds Design; Metal Weight Data; Physical Properties of Pipe; and 3D Offset Calculator
Hardware
For computer compatible with Microsoft Excel-97 or later.
Developer
Ben A. Nottingham
RE: Max Allowable Working Pressure for Welded & Npt Piping
RE: Max Allowable Working Pressure for Welded & Npt Piping
is it possible to get a copy of this spreadsheet that you mentioned? or can u tell me how i can put one together?
thanks,
RE: Max Allowable Working Pressure for Welded & Npt Piping
Ben (ben4piping) is being far too modest. Ben's PipingOffice suite of ExCel spread sheet templates are far more useful than he describes in this thread. The suite has saved me an enormous amount of time through the years. Some of the capability of the suite includes the following:
Pipe Allowable Pressure per B31.3
High Pressure Pipe per B31.3 Ch-IX
Pipe Allowable Pressure per B31.1
Branch Reinf per B31.3
Branch Reinf per B31.1
Mitered Ell per B31.3
Mitered Ell per B31.1
Safety Valve Reactions per B31.1 Appendix II, (impact forces)
Support Span, Shoe Bearing, ....
SIFs per B31.3
SIFs per B31.1
Theoretical External Collapse Pressure
Jacketed Pipe Theoretical Column Buckling
Pipe Dimensional and Material Properties
3-D offset, Triangle Calcs, Dimen Calcs
You can contact Ben at:
bnottingham@chartertn.net
Regards, John.