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Method and apparatus to selectively reduce wellbore pressure during pumping operations

  • US 7,128,152 B2
  • Filed: 01/19/2004
  • Issued: 10/31/2006
  • Est. Priority Date: 05/21/2003
  • Status: Expired due to Fees
First Claim
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1. A service tool for use in a well, comprising:

  • a tubular having a central passageway therethrough;

    a crossover through which fluid flowing down the central passageway can exit the central passageway and enter a lower annulus below a packer and fluid flowing up the central passageway can exit the central passageway and enter an upper annulus above the packer;

    a valve having a housing mounted to the tubular, the valve being positioned to allow or block fluid flow from the lower annulus into the central passageway through an opening in a wall of the tubular, in which the valve further comprises a piston sealingly and moveably mounted within the housing; and

    a responsive member mounted in a wall of the housing, wherein the responsive member must be transitioned from a closed position to an open position to enable fluid flow through the wall for actuation of the valve.

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