Abstract: A displacement amplifier interconnects a piezoelectric actuator with a displacement member and comprises respective bellows members of differential diameter defining first and second expansible chambers which are liquid filled and respond to linear displacement of a stack of piezoelectric disks to provide an amplified linear displacement to the displacement member. The transducer is particularly useful as a signal transmitting or receiving transducer for acoustic wave generation or measurement for wellbore logging tools.

Abstract: In a fluid flow line from a well in the earth, a choke means is employed to restrict the flow of fluids through that line. The choke has a body with apertures therein for passing fluid therethrough and an insert means in one of the apertures of the body which mates with a movable means for creating the choking restriction. The insert means extends to the fluid outlet end of the body of the choke and for a finite distance beyond and outside the body of the choke so that any blast effect that may occur due to pressure change inside the insert means is transferred by the insert means outside of the body of the choke before being released.

Abstract: A flow line control valve is provided with internal erosion and corrosion trim liners and means for detecting for leaks in the liners. There is also provided fuller range, positive shutoff throttle means designed to reduce erosion and corrosion of the throttling parts and valve seat. The low flow rate throttling action is provided by progressive and accumulative flow through one or more stages of throttling flow passages of and by a nose end of the throttling means. Preferably the nose end is concavely tapered. Also preferably two or more stages of throttling spaced apart flow passages of increasing size are employed. Postive long lasting shut-off is assured by combining throttling and seat surfaces of different angles of taper.

Abstract: Oxygen and propane are supplied to the combustion chamber of a marine seismic gas exploder from a pair of pressure regulated gas charging cylinders. Ignition of the resultant explosive gas mixture drives a piston connected with means for creating an acoustic disturbance in the water. The outputs from the charging cylinders are fed simultaneously to a mixing manifold connected to a large orifice communicating with the combustion chamber.The ratio of gases in the resultant mixture is automatically determined by the relative volumes and pressures of the charging cylinders, which may be precisely regulated by adjustment of pistons movable within such cylinders and by gas pressure regulation. To safeguard against too rapid voiding of a small volume charging cylinder, voiding of the larger volume cylinder may be initiated first with the aid of a choke downstream of the manifold. This will create an artificial back pressure in the distribution system.