Subsea actuator for actuating a subsea rotating component, as well as a method of operating an actuator

• Main Authors: Rinde Brauti, Espen, Landa, Simen, Magnus, Heyn Halfdan
• Format: Patent
• Language: English
• Published: 28.10.2019
• Subjects: ACTUATING-FLOATS; BLASTING; COCKS; DEVICES FOR VENTING OR AERATING; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MECHANICAL ENGINEERING; TAPS; THERMAL INSULATION IN GENERAL; VALVES; WEAPONS

The following invention relates to a subsea actuator (16′; 16″) for actuating a subsea rotating component (81; 181); comprising: a first biasing element (82; 182); a motor (85; 185); a holding element (83; 100, 183) configured to receive an input force; a rotatable stem (80′, 80″, 250, 84; 80; 200) operatively connectable to the component; a force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201; 84, 99, 86, 101, 83) connectable to the first biasing clement (82; 182) and the holding element (83; 100, 183); a first connection which in a first mode is configured to lock the stem (80′, 80″, 250, 84; 80; 200) in a rotatable engagement with the motor (85; 185) and in a second mode is configured to unlock the stem (80′, 80″, 250, 84; 80; 200) from the rotatable engagement with the motor (85; 185) and allow the stem (80′, 80″, 250, 84; 80; 200) to be influenced by the first biasing element (82; 182); wherein the first biasing element (82; 182) and the stem (80′, 80″, 250, 84; 80; 200) are releasably connected via the force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201; 84, 99, 86, 101, 83), such that when the first biasing element (82; 182) and the stem (80′, 80″, 250, 84; 80; 200) are released from each other, the first biasing element (82; 182) is configured to be pre-tensioned to a position representing a first pre-tensioned position of the actuator (16′; 16″) without operating the stem (80′, 80″, 250, 84; 80; 200); the holding element (83; 100, 183) is configured to exert a holding force on the force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201) and the first biasing element (82; 182) in the first pre-tensioned position; and wherein, when the first biasing element (82; 182) and the stem (80′, 80″, 250, 84; 80; 200) are connected and the first biasing element (82; 182) is pre-tensioned, the first connection is in the first mode such that the motor (85; 185) is configured to operate the stem (80′, 80″, 250, 84; 80; 200) to a position representing a second pre-tensioned position of the actuator (16′; 16″); wherein, in the second pre-tensioned position, upon loss of input force to the holding element (83; 100, 183), the holding element (83; 100, 183) is configured to release its holding force on the force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201; 84, 99, 86, 101, 83) and the first biasing element (82; 182), thereby the first connection is unlocked to its second mode, such that the pre-tensioned first biasing element (82; 182) is released and rotates the stent (80′, 80″, 250, 84; 80; 200) to a position representing a release position of the actuator (16′; 16″).