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Safety Valve Calculator
Calculate safety/relief valve orifice area per API 520 / API 521.
psig
°F
lb/lbmol
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—
C Coefficient
327
API 526 Orifice Area Table
| Letter | Area (in²) | Area (cm²) |
|---|---|---|
| D | 0.110 | 0.71 |
| E | 0.196 | 1.26 |
| F | 0.307 | 1.98 |
| G | 0.503 | 3.25 |
| H | 0.785 | 5.06 |
| J | 1.287 | 8.30 |
| K | 1.838 | 11.86 |
| L | 2.853 | 18.41 |
| M | 3.600 | 23.23 |
| N | 4.340 | 28.00 |
| P | 6.380 | 41.16 |
| Q | 11.050 | 71.29 |
| R | 16.000 | 103.23 |
| T | 26.000 | 167.74 |