Read more about pressure calculations

Sandvik's online pressure calculation is a tool that provides estimates of the highest permissible internal pressure for tube and pipe of certain sizes and Sandvik grades. The result of each calculation is presented as an approximate maximum working pressure.

Due to the differences in national regulations, this type of calculations differ from country to country, and many limitations exist. We have, therefore, chosen to present the following standards:

We also present German standard (DIN 2413 2011-06)3) and former Swedish Code (RN 78) for reference purposes.

1) Maximum internal pressure is provided in ksi. (1 ksi = 6.895 MPa)
2) Maximum internal pressure is provided in bar. (1 bar = 0.1 MPa)
3) See more information regarding the validity of DIN 2413 (2011-06) for dimensioning of hydraulic systems.

Attention regarding the validity of DIN 2413 (PDF document, 83 kB)

The proof strength up to 400°C (752°F)1) is provided for each grade.

There are two separate wall thickness tolerances for each standard:

  • Wall thickness tolerance ±12.5%, T22). This tolerance covers most pipe sizes according to ANSI/ASME SA312 with tolerances according to A999 (A530).
  • Wall thickness tolerance ±10% T33). This tolerance is valid for all small diameter tubing(<19 mm) and most cold finished tubes.

Pay attention to the wall thickness limitations for the special grades.

Please note: The pressures suggested are only given as guidance. Dimensioning of piping systems is also dependent on external forces, thermal stress, static weight etc. Furthermore the design must be made according to regulations from local authorities and be approved accordingly.

To find full explanation which particular wall thickness tolerance is valid check with our stock standard catalogue S-110.

1) Above 400°C (752°F) creep strength may have to be considered.

2) The calculations are based on ±12.5% only, despite the complete T2 definition "±12.5%, but min. ±0,4 mm".

3) The calculations are based on ±10% only, despite the complete T3 definition "±12.5%, but min. ±0,2 mm".

Tolerances according to ISO 1127
Condition Outside diameter Wall thickness
Cold-worked tube ±0.75%, but min.
±0.3 mm (D3)
±10%, but min.
±0.2 mm (T3)
Hot-worked tube ±1.0%, but min.
±0.5 mm (D2)
±12.5%, but min.
±0.4 mm (T2)3)

4) Valid for wall thicknesses min. 4 mm and where the ratio between wall thickness and outside diameter is min. 1:10. The tolerance for other sizes is ±15%, but min. ±0.6 mm (T1).