Line List — Wall Thickness and Flange Rating

FIG. 1 | ASME B31.3 process piping | ASME B16.5 flange ratings

P&ID:

Drawing No:

Asset Number:

Customer:

By:

Project Mgr:

Rev:

Date:

ASME Code: B31.3 2020 EDITION Flanges: B16.5 Group 1.1 REVISION 0

Warnings

Identification						Design Conditions			Pipe Properties							Calculation Parameters						Results				Flange Check
Spool #	Line No.	Service Desc.	From	To	Size	Design Press. P (psig)	Design Temp (°F)	Flange & Fitting Class	Pipe OD (inch)	Pipe Sch.	Material	Pipe Type	Allow. Stress S (psi)	Wall Th. t (inch)	C.A. (inch)	Mill Tol. (12.5%)	Thread Depth	Avail. Wall Th.	Joint Eff. E/W	Y Coeff	Req'd Wall Th.	Margin (Avail-Req)	X-Ray %	Stress Relief	Hydro Test Press. (psi)	B16.5 Allowed	Flange Status

Method

Required wall thickness from ASME B31.3 paragraph 304.1.2, Equation 3a for straight pipe under internal pressure: t = (P × D) / (2 × (S × E × W + P × Y)). The allowable stress S and coefficient Y are looked up server-side from ASME B31.3 Table A-1 / Table 304.1.1 for the selected material at the design temperature (linearly interpolated; a material or temperature outside the published table is flagged, never extrapolated). The reported required wall column adds the corrosion allowance and any thread depth to t.

Available wall thickness applies the 12.5% mill tolerance per ASME B36.10M to the nominal wall, then subtracts the corrosion allowance and thread depth. The margin column is available minus required. A negative margin fails the check.

Flange rating check looks up the ASME B16.5 working pressure for the selected class at the design temperature, using the material group of the flange material (e.g. F304/F316 austenitic stainless are rated on Group 2.1/2.2 — not the carbon-steel table). The check compares this against the design pressure. A material that cannot be mapped to a B16.5 group is flagged, not passed. Lines with no flanges (welded only) or B16.11 forged fittings (Class 3000/6000) show N/A.

Hydrostatic test pressure is calculated per ASME B31.3 paragraph 345.4.2, taken as 1.5 × design pressure × (S_ambient / S_design) with the stress ratio capped at the values published in B31.3 Table A-1.

Cyclogen5D · Calgary, AB · ASME Section VIII Div. 1 and B31.3 engineering for separation and pressure equipment.
Calculations on this page run server-side against current pipe tables and material data. Get a project quote.