Pressure
Convert pound per square inch (psi) to bar (bar). Pressure is force per unit area. Process engineers move constantly between SI (kPa, bar) and US (psi) units, and between absolute and gauge.
1 psi = 0.06894757 bar
To convert pound per square inch to bar, multiply the psi value by 0.06894757. To go the other way, divide by 0.06894757 (or multiply by 14.50377).
| psi | bar |
|---|---|
| 1 | 0.06894757 |
| 2 | 0.1378951 |
| 5 | 0.3447378 |
| 10 | 0.6894757 |
| 25 | 1.723689 |
| 50 | 3.447378 |
| 100 | 6.894757 |
| 250 | 17.23689 |
| 500 | 34.47378 |
| 1000 | 68.94757 |
Line and vessel ratings, pump discharge heads, and relief set points are all specified in pressure units — usually psi or barg in the field and kPa in calculations.
Always track whether a value is absolute or gauge: 0 barg equals about 101.3 kPa absolute, and mixing the two is a common and costly error.
Worked example. A pressure of 145.0377 psi is 10 bar.
Multiply the value in psi by 0.06894757 to get bar. For example, 10 psi = 0.6894757 bar.
1 psi equals 0.06894757 bar.
Line and vessel ratings, pump discharge heads, and relief set points are all specified in pressure units — usually psi or barg in the field and kPa in calculations.