Multiplier digital-hydraulic well control system and method

An apparatus for transmitting pressurized fluid between a wellbore surface and a well tool located downhole in the wellbore, comprising:

• at least two hydraulic lines engaged with the well tool for conveying the fluid to the well tool, each hydraulic line providing communication control signals to actuate the well tool and providing fluid pressure to operate the well tool;
• and
• a controller selectively pressurizing the fluid within each hydraulic line and thereby providing the communication control signals in a predetermined fluid pressure sequence to select the well tool for actuation, and the controller applying a predetermined pressure to actuate the well tool.

A method of hydraulically controlling multiple well tools in a well, the method comprising the steps of:

• interconnecting a plurality of hydraulic lines to each of the tools;
• and
• selecting a first one of the tools for actuation thereof by generating a first predetermined pressure on a first combination of the hydraulic lines, the first pressure being generated on the first combination of the hydraulic lines in a first predetermined sequence in which the first pressure is applied successively to selected ones of the first combination of the hydraulic lines.