| Result | Value | Unit |
|---|---|---|
| Dome Pressure at 60°F | — | psig |
| Absolute Dome Pressure | — | psia |
| Temperature Correction Factor (m) | — | Equation factor |
| Closing Pressure at Valve Temperature | — | psig |
Step 1 — Dome pressure at 60°F: P_dome = TRO × (1 − R)
Step 2 — Convert to absolute pressure: P_dome,abs = P_dome + 14.7, with pressures in psi.
Step 3 — Calculate temperature factor m: the supplied piecewise polynomial is selected using absolute dome pressure of 1,238 psia as the boundary.
Step 4 — Correct closing pressure for valve temperature: P_closing = P_dome + m × (T_valve − 60).
Engineering note: This form preserves the equations from the supplied legacy code. The original source also declared tubing pressure, casing pressure, and valve type, but did not use them in its calculation; they are therefore not included as inputs here. Confirm the applicable valve-manufacturer procedure, pressure basis, and equation units before using results for field decisions. This is a troubleshooting calculation, not a substitute for gas-lift valve design or operating procedures.
