John D Chisholm

US Patent:

50497430, Sep 17, 1991

Filed:

Jan 17, 1990

Appl. No.:

7/466237

Inventors:

Lawrence Taylor - Katy TX
John W. Chisholm - Houston TX
Philip T. Thayer - Littleton CO

Assignee:

ProTechnics International, Inc. - Houston TX

International Classification:

G21H 502

US Classification:

250303

Abstract:

The present disclosure is directed to a method and apparatus for controllably injection a radioactive isotope tracer fluid into a fracture fluid, a manifold or mud flow line connected to a well. It is best used in measuring well stimulation procedures based on injection of tracer isotopes so that stimulation performance data can be obtained by gamma ray spectroscopic measuring instruments lowered in the well borehole after fracture. The present apparatus utilizes a tank supply of tracer fluid connected through a pump into the mud line wherein the pump drives a tachometer, and utilizes a CPU to respond to pumping rate measurements and adjust the pumped rate of the tracer fluid.

US Patent:

56082142, Mar 4, 1997

Filed:

Oct 30, 1995

Appl. No.:

8/550287

Inventors:

Emilio A. Baron - Missouri City TX
David J. Berneking - Houston TX
John W. Chisholm - Houston TX
Marc K. Fisher - Katy TX
William F. Trainor - Houston TX
James R. Foreman - Sugarland TX

Assignee:

Protechnics International, Inc. - Houston TX

International Classification:

G01V 512

US Classification:

250262

Abstract:

A gamma ray spectral tool is provided that can be used in slick line systems. The tool includes a battery, a controller, and a memory. In operation, the tool compresses data from the spectral detector for storage in the memory, allowing for long runs without the memory overflowing. Further, a controller latches the self-adjusting stabilization feature of the spectral detector when gamma ray intensity exceeds a predetermined threshold, preventing erroneous "stabilization" by the stabilization feature of the spectral detector.