Probe Technology Services, Inc.

Other

Brian Hurst

John L Marshall

David S Wesson

Marvin Beckman

David M O'Connor

A method for initializing the input of each of m receiver channels of a receiving transducer in a well logging tool comprising the steps of selecting a logging tool having a multi-element receiving transducer wherein each element of the multi-element receiving transducer operates in an anti-resonant mode below its resonant frequency, and executing a routine in an initialization mode wherein a predetermined number of run cycles are operated and receiver input responses are measured and averaged for each of the m channels while transmitter firing signals are disabled.

Method for initializing receiver channels in a cement bond logging tool

Pressure-actuated electrical switches are provided that comprise a housing having a slidable piston therein. The slidable piston slides from a first position to a second position and in so doing switches an electrical path from a first electrical contact and a second electrical contact to an electrical path between the first electrical contact and a third electrical contact. Suitable applications of such switches include any application in which a pressure wave is used to actuate an electrical switch. The pressure-actuated electrical switches of the present invention are especially adapted for use in controlling successive detonations in a downhole perforation gun, as explosive gases and pressure waves are used to actuate the slidable piston so as to trigger a subsequent detonation charge. Perforation guns utilizing these pressure-actuated electrical switches and corresponding methods of use are also provided herein.

Perforation gun pressure-actuated electrical switches and methods of use

Methods and devices are provided for controlling detonation of explosives in a well bore for perforation or a well bore casing, which avoid or reduce unintentional or undesirable detonations while ensuring or increasing desirable detonations. An explosive trigger system or tool may comprise a central processing unit (CPU), memory, and one or more sensors disposed for measuring one or more downhole conditions. Downhole conditions may be measured with the sensor and then used to program detonation parameters (such as temperature or pressure) or preconditions (such as time or distance traveled) to the trigger system. Detonation can only occur when the programmed parameters or preconditions are satisfied. In this way, undesirable detonations are avoided by requiring certain preconditions to arming the trigger system. To further control arming and/or detonating, a line sequencer may be provided, wherein energy is propagate down along the physical deployment line as pulses or line 'jerks' through mechanical manipulations of physical deployment line near surface. These pulses can form signals for downhole control of the trigger system.

Firing trigger apparatus and method for downhole tools

A longitudinally segmented acoustic transducer for a cement bond logging (CBL) tool having a plurality of adjoining PZT ring-like segments driven synchronously in parallel by one or more pulses and caused to vibrate in an anti-resonant mode, substantially below the resonant frequency of an individual segment when used in a transmitting application. When used in a receiving application, each of the plurality of transducer rings are caused to vibrate by acoustic signals detected by the transducer array, also in an anti-resonant mode. High speed digital signal processing enables on-depth, high quality data for all azimuths at each depth to be obtained, processed, normalized and either sent to the surface in real time for each 20 Hz firing cycle, as the CBL tool is pulled toward the surface, or stored in a memory module in digital form for later retrieval. Built-in calibration factors used for normalizing the output signals to the operating conditions of use may be accessed at any time.

Growing community of inventors

Mineral Wells, TX, United States of America

Brian Hurst