Abstract: A transducer member is made from a piezoelectric material (e.g. barium titanium) having a looped configuration and a gap in the loop and having properties of vibrating upon the introduction of an electrical voltage to the transducer member. A support member made from steel or aluminum and having a looped configuration and enveloping, and attached to, the transducer member has a gap aligned with the transducer member tap and has properties of vibrating with the transducer member. The transducer member may have a uniform thickness around its periphery or a progressively increasing thickness with progressive distances from the gap. The transducer has a high mechanical Q (e.g. 8-12) and a particular resonant frequency when disposed in air or in a vacuum. When the transducer is disposed below the earth's surface, its resonant frequency may vary because of variations in the earth's characteristics at the different positions.

Abstract: A transducer provides (a) increased magnitudes of vibrations without cracking and (b) increased power to the transducer, in response to alternating voltages, for producing transducer vibrations with increased magnitudes. A polycrystalline ceramic (e.g. polycrystalline lead titanate or polycrystalline lead zirconate) has a looped configuration with a gap and has properties of vibrating upon an introduction of an alternating voltage, preferably rich in harmonies, to the ceramic. The ceramic is cryogenically treated as by initially reducing its temperature to approximately −100° C., then disposing the ceramic in liquid nitrogen and thereafter gradually increasing its temperature to approximately room temperature. This increases the dielectric strength of the ceramic by prestressing the ceramic, thereby providing for the ceramic to receive increased voltages without cracking. An alternating voltage rich in harmonics (e.g. square wave voltage) may be applied to the ceramic.

Abstract: A support member preferably made of a metal such as cold rolled steel is disposed in a looped configuration and is provided with a gap. A transducer member preferably made of a piezoelectric material such as a ceramic is disposed within the support member. The transducer member is provided with a gap at a position corresponding to the gap in the support member. A closure member made from a suitable springlike material such as an alloy steel is attached to the opposite ends of the support member at the position of the gap as by welding. The closure member extends in a U-shaped configuration into the looped configuration (in section) defined by the support member and the ceramic member. The axial length of the closure member defines the bandwidth of the frequency vibrations generated by the transducer member.

Abstract: A transducer assembly includes a piezoelectric transducer and a support member encasing the transducer. The transducer and the support member may have commonly disposed openings. The support member has a progressively increasing thickness at progressive positions from the opening to distribute equally the stresses at the different positions on the piezoelectric transducer. A plurality of such transducer assemblies may be disposed at spaced positions in an oil well with the support members supported on a support rail extending through the well. The support rail serves as an electrical ground. A bus bar extends through the well at positions corresponding substantially to the centers of the transducer assemblies. The bus bar is supported by electrically insulating spacer members extending from the support rail. A ring is supported at one end by the support rail and is coupled at the other end to a tubing. The tubing envelopes, the transducer assemblies, the support rail, the bus bar and the spacer members.

Abstract: A transducer assembly includes a piezoelectric transducer and a support member encasing the transducer. The transducer and the support member may have commonly disposed openings. The support member has a progressively increasing thickness at progressive positions from the opening to distribute equally the stresses at the different positions on the piezoelectric transducer. A plurality of such transducer assemblies may be disposed at spaced positions in an oil well with the support members supported on a support rail extending through the well. The support rail serves as an electrical ground. A bus bar extends through the well at positions corresponding substantially to the centers of the transducer assemblies. The bus bar is supported by electrically insulating spacer members extending from the support rail. A ring is supported at one end by the support rail and is coupled at the other end to a tubing. The tubing envelopes, the transducer assemblies, the support rail, the bus bar and the spacer members.

Abstract: A transducer assembly includes a piezoelectric transducer and a support member encasing the transducer. The transducer and the support member may have commonly disposed openings. The support member has a progressively increasing thickness at progressive positions from the opening to distribute equally the stresses at the different positions on the piezoelectric transducer. A plurality of such transducer assemblies may be disposed at spaced positions in an oil well with the support members supported on a support rail extending through the well. The support rail serves as an electrical ground. A bus bar extends through the well at positions corresponding substantially to the centers of the transducer assemblies. The bus bar is supported by electrically insulating spacer members extending from the support rail. A ring is supported at one end by the support rail and is coupled at the other end to a tubing. The tubing envelopes, the transducer assemblies, the support rail, the bus bar and the spacer members.

Abstract: A casing in an oil well is constructed to provide for the flow of oil in the well. The casing cylindrical and may be perforated. The casing is resonant in a hoop mode at a particular fundamental frequency such as approximately 400 hertz. A transducer includes a transducer member disposed within a tubing in spaced relationship to the tubing. The transducer member may be a ceramic slotted at one end and supported by the tubing at the other end. A ring may envelope the ceramic member and may be slotted at the same position as the ceramic member. The tubing may be filled with a fluid which provides dielectric properties and operates to transmit vibrations from the transducer to the tubing. The transducer may vibrate in the hoop mode at the fundamental frequency of resonance of the casing. These vibrations are transmitted to the casing through the fluid in the tubing, the tubing and the oil in the casing to produce a resonance of the casing at the particular fundamental frequency in the hoop mode.

Abstract: A support member preferably made of a metal such as cold rolled steel is disposed in a looped configuration and is provided with a gap. A transducer member preferably made of a piezoelectric material such as a ceramic is disposed within the support member. The transducer member is provided with a gap at a position corresponding to the gap in the support member. A closure member made from a suitable springlike material such as an alloy steel is attached to the opposite ends of the support member at the position of the gap as by welding. The closure member extends in a U-shaped configuration into the looped configuration (in section) defined by the support member and the ceramic member. The axial length of the closure member defines the bandwidth of the frequency vibrations generated by the transducer member.