Burst Pressure Calculator (API TR 5C3) - Rapid Global

Internal Yield (Burst) Pressure — Calculation Sheet

Internal Yield (Burst) Pressure

Pipe and tubing body capacity — API TR 5C3

Standard	API TR 5C3
Method	Barlow equation
Applies to	Pipe body, zero axial load

Inputs

Grade API 5CT grade you’re specifying. Choose Custom if you need to enter a non-standard or mill-specific yield value. Minimum yield strength, Yp (psi) Auto-fills from grade (API minimum). Replace with the actual value from the mill test report if you have it — mill yield often runs above the API minimum. Outside diameter, D (in) Pick a standard API 5CT nominal OD, or choose “Custom OD” and type your own value in the field below — for a non-standard OD or a size not in the list. Nominal wall thickness, t (in) Nominal pipe body wall thickness from your spec sheet. Not the same as drift diameter or ID. API wall factor Applied to the nominal wall thickness. API TR 5C3 uses 0.875 for the standard minimum-wall design case (accounts for the −12.5% manufacturing tolerance). Use 1.0 for a nominal-wall screening estimate. Default here is 1.

Units

Result

14,337 psi

98.8 MPa

P = factor × 2 × Yp × t ÷ D

= 1 × 2 × 55,000 × 0.361 ÷ 5.500

Grade	—
Yp (yield strength)	—
D (outside diameter)	—
t (wall thickness)	—
API wall factor	—
Result — internal yield pressure	—

Reference & methodology

Standard: API TR 5C3 (formerly API Bulletin 5C3), Technical Report on Equations and Calculations for Casing, Tubing, and Line Pipe Used as Casing or Tubing — equivalent methodology to ISO 10400.

Formula basis: Barlow’s thin-wall equation, with a user-selectable wall factor applied to nominal wall thickness. API TR 5C3 uses 0.875 for the standard minimum-wall design case, accounting for the −12.5% wall thickness manufacturing tolerance permitted under API 5CT. Set the factor to 1.0 for a nominal-wall screening estimate instead — this calculator defaults to 1.0, so change it to 0.875 if you need the standard minimum-wall design value.

Scope and limitations: This gives the pipe body internal yield pressure at zero axial load only. It does not account for combined loading (axial tension or compression plus internal pressure, or bending), temperature derating, or connection pressure rating — on a made-up string, the connection often governs the working pressure, not the pipe body.

For preliminary screening only. Not a substitute for a full triaxial (von Mises) load-case analysis or a certified engineering assessment.

Want to see where this formula comes from and why the wall factor matters? Read The Logic Behind Our Internal Yield (Burst) Pressure Calculator.

Checking external pressure instead? Try the Collapse Pressure calculator.

Need triaxial load-case analysis or connection re-rating? Talk to an engineer