Pressure
Convert inch of mercury (inHg) 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 inHg = 0.03386389 bar
To convert inch of mercury to bar, multiply the inHg value by 0.03386389. To go the other way, divide by 0.03386389 (or multiply by 29.52998).
| inHg | bar |
|---|---|
| 1 | 0.03386389 |
| 2 | 0.06772778 |
| 5 | 0.1693195 |
| 10 | 0.3386389 |
| 25 | 0.8465973 |
| 50 | 1.693195 |
| 100 | 3.386389 |
| 250 | 8.465972 |
| 500 | 16.93194 |
| 1000 | 33.86389 |
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 295.2998 inHg is 10 bar.
Multiply the value in inHg by 0.03386389 to get bar. For example, 10 inHg = 0.3386389 bar.
1 inHg equals 0.03386389 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.