PCT No. PCT/FR92/00203 Sec. 371 Date Dec. 14, 1992 Sec. 102(e) Date Dec. 14, 1992 PCT Filed Mar. 5, 1992 PCT Pub. No. WO92/15768 PCT Pub. Date Sep. 17, 1992.A method of verifying that a safety valve, normally biased to a closed position and opened by hydraulic pressure applied thereto by a fluid supplied at a constant flow rate, is operating correctly within an oil well involves comparing reference and operating curves associated with the valve. The reference curve represents the hydraulic pressure over time applied to the safety valve to open the valve when the valve is operating correctly. The operating curve is prepared with the safety valve installed within an oil well and also represents the hydraulic pressure over time applied to the safety valve to open the valve. Any deviation between the reference and operating curves indicates a potential malfunction and, possible, a precise type of malfunction associated with the safety valve.
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