ACTUATOR FOR DOWNHOLE INSTRUMENTS Russian patent published in 2002 - IPC

FIELD: oil and gas producing industry, particularly, actuators in downhole instruments for perforation. SUBSTANCE: actuator for downhole instruments has a body, electric resistor for current heating of water, electrodes for current input and output; electrical insulators; water for steam production; members of automatic current switching on and off; instrument head for connection with cable head; channels for passage of working fluid to power device. Electrodes are used in the form of insulated rod and body. Electric resistor included into electric circuit is a part of water for steam production with control of its resistance in gap between electrodes. Movable and fixed electrodes are installed as members of current automatic switching on and off. They have tie-rod for interaction of electrodes and tie-rod with members of actuator and for motion of movable electrode. EFFECT: provided compactness and simplified design of actuator, increased service life of electric resistor. 1 dwg