SYSTEM AND METHOD FOR DETERMINING THE START TIME OF A PRESSURE PULSE FROM A DOWNHOLE EXPLOSIVE DEVICE

摘要

A system and method for use in determining the start time of a pressure pulse created by a downhole explosive device detonated by a firing signal includes a downhole tool with a pressure pulse detector that detects the pressure pulse and generates an input signal in response thereto, and a circuit path configured to output a signaling pulse distinguishable from the firing signal. A surface unit receives and discriminates the signaling pulse from the firing signal, and outputs a start time signal in response to receiving the signaling pulse. Alternatively, the downhole tool includes a processor that measures and stores the time that the pressure pulse detector generates the input signal.

主权项

1. A system for creating a start time signal in response to a pressure pulse created by a downhole explosive device detonated by a firing signal, the system comprising:
(a) a downhole tool comprising:
(i) a pressure pulse detector for detecting the pressure pulse and generating an input signal in response to detecting the pressure pulse; and(ii) a circuit path operatively connected to the pressure pulse detector, and configured to output a signaling pulse having a signal parameter distinguishable from the signal parameter of the firing signal, in response to the input signal; and (b) a surface unit comprising a circuit path operatively connected to the downhole tool circuit path, and configured to discriminate the signaling pulse from the firing signal, and to output the start time signal in response to receiving the signaling pulse.