# Design formula for steel pipe.

**Citation:** 49 CFR 192.105  
**Type / status:** regulation / current  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 2026-08-18  
**Published:** Not stated

(a) The design pressure for steel pipe is determined in accordance with the following formula:

P = (2 St/D) × F × E × T

P = Design pressure in pounds per square inch (kPa) gauge. S = Yield strength in pounds per square inch (kPa) determined in accordance with § 192.107. D = Nominal outside diamete

## Document text

(a) The design pressure for steel pipe is determined in accordance with the following formula:

P = (2 St/D) × F × E × T

P = Design pressure in pounds per square inch (kPa) gauge. S = Yield strength in pounds per square inch (kPa) determined in accordance with § 192.107. D = Nominal outside diameter of the pipe in inches (millimeters). t = Nominal wall thickness of the pipe in inches (millimeters). If this is unknown, it is determined in accordance with § 192.109. Additional wall thickness required for concurrent external loads in accordance with § 192.103 may not be included in computing design pressure. F = Design factor determined in accordance with § 192.111. E = Longitudinal joint factor determined in accordance with § 192.113. T = Temperature derating factor determined in accordance with § 192.115.

(b) If steel pipe that has been subjected to cold expansion to meet the SMYS is subsequently heated, other than by welding or stress relieving as a part of welding, the design pressure is limited to 75 percent of the pressure determined under paragraph (a) of this section if the temperature of the pipe exceeds 900 °F (482 °C) at any time or is held above 600 °F (316 °C) for more than 1 hour.

[35 FR 13257, Aug. 19, 1970, as amended by Amdt. 192-47, 49 FR 7569, Mar. 1, 1984; Amdt. 192-85, 63 FR 37502, July 13, 1998]

## Provenance

- Official: Yes
- Source: <https://www.ecfr.gov/on/2026-08-18/title-49/section-192.105>
- Source ID: `ecfr`
- SHA-256: `a73041b815c56408809e7a5ce71b0d0faf7d25af3e6cbeb155a659292e6d4233`
- Retrieved: 2026-08-20T05:54:34.435Z
- Exported: 2026-08-23T10:37:36.898Z
- Document slug: `49-cfr-192-105`

### Source metadata

```json
{
  "cfrTitle": 49,
  "part": "192",
  "section": "192.105",
  "subpart": "Subpart C—Pipe Design",
  "corpusVersion": "2026-08-18",
  "jurisdiction": "US"
}
```