Abstract: 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.

Abstract: A production tube which includes at least one substantially tubular tube element and a hydraulic line. The tube element is provided with a longitudinal groove for receiving the hydraulic line.

Abstract: Method has been provided for cleaning a vertical, deviated or horizontal underground well. In which a maintenance tubing having a cleaning head at its end is lowered into a production pipe for suction of sediments. At a certain level above the region of the well to be cleaned, a hydraulic isolation device is installed in the annulus between the maintenance tubing and the production pipe. Fluid is injected into the annulus to activate the hydroejector which is located above the hydraulic isolation device to cause the suction of the sediments. The sediments downhole therefore can be cleaned out without introducing foreign fluid downhole.

Abstract: Electric connector for use with underwater well head. This device comprises a coaxial cylindrical male element 20 of the suspension connector 3 of the tubing 15 in the well head 2, fixed to the suspension connector 3 by a ring element 23 bored by at least one passage 24 for the effluent and bearing on its cylindrical outline three metallic ring contacts 25, 26, 27 connected through the body of the male element 20 and the connector to the conductors of a cable 19 leading to a motor 16 and a female element 21 in the form of a cylindrical bell adapted to slide along the male element 20 and bearing three electric contacts 28, 29, 30 corresponding to the contacts of the male element 20, these contacts being connected to an electric power supply, a delivery pipe 31 for neutral gas issuing at the bottom of the cylindrical bell 22.Such a connector is adapted to supply the offshore deep well pumps with electric power.