06536530 is referenced by 48 patents and cites 4 patents.

A hydraulic control system for downhole tools enables convenient selection and actuation of a well tool assembly from among multiple well tool assemblies installed in a well. Each well tool assembly includes a control module having a selecting device and a fluid metering device. A predetermined range of pressure levels on one of multiple hydraulic lines causes the well tool assembly to be selected for actuation, a differential between pressure on that hydraulic line and pressure on another hydraulic line determines a manner of actuating the selected well tool assembly, and pressure fluctuations on one of the hydraulic lines causes fluid to be transferred from another hydraulic line to an actuator of the well tool assembly.

Title
Hydraulic control system for downhole tools
Application Number
9/848562
Publication Number
6536530 (B2)
Application Date
May 3, 2001
Publication Date
March 25, 2003
Inventor
Jimmie R Williamson Jr
Carrollton
TX, US
Paul D Ringgenberg
Spring
TX, US
Roger L Schultz
Aubrey
TX, US
Agent
J Richard Konneker
US
Assignee
Halliburton Energy Services
TX, US
IPC
E21B 34/10
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