Patent ID: 8272439
Filing Date: 2012-09-25
Classification: E21B

Abstract:
1. An apparatus comprising: a wellbore commencing at a surface and confining a well casing; a depth determination device in sliding communication with said well casing, said depth determination device providing a module attachment portion configured for direct attachment and detachment of a perforation device to said depth determination device; a processor secured within said depth determination device; an electronic location sensing system integrated within said depth determination device, and communicating with said processor, said electronic location sensing system interacting exclusively with features of said well casing to electronically determine a location of said depth determination device within said well casing, in which said depth determination device is physically connected with said surface via at most a fluidic material, and further in which said electronically determined location of said depth determination device within said well casing is data used by said processor and wherein said electronically determined location of said depth determination device within said well casing is available at said surface only upon retrieval of said depth determination device from said well casing to said surface; and a communication port provided by said module attachment portion accommodating a communication of operational commands from said processor to said perforation device when said perforation device is attached to said module attachment portion.