초록 ▼

A wireless coiled tubing joint locator for locating joints or collars in a production tubing string. An electromagnetic coil assembly or giant magnetoresistive digital field sensor senses the increased mass of a pipe joint, and provides a signal to an electric circuit which generates a signal receiv

A wireless coiled tubing joint locator for locating joints or collars in a production tubing string. An electromagnetic coil assembly or giant magnetoresistive digital field sensor senses the increased mass of a pipe joint, and provides a signal to an electric circuit which generates a signal received by a pilot solenoid valve. The solenoid valve momentarily opens a pilot passageway which activates a piston to close a circulation port in the joint locator, resulting in an increase in a surface pressure reading observable by the operator. In one embodiment, a rupture disk is provided so that pressure cannot be applied to any downhole tool below the joint locator prematurely. A seat sleeve prevents premature communication of fluid to the rupture disk but can be opened by dropping a ball into the joint locator. A second embodiment may be used for either logging or washing operations or both. The electronic circuit can provide a selected one of a plurality of time delays. A fixed test period in the circuit delays activation of the time delay so that the joint locator may be tested before it is run into the well. The electric circuit and power supply are provided in a removable case.

대표청구항 ▼

[ What is claimed is:] [1.]1. A well pipe string joint locator for use in a pipe string, said locator comprising:a housing having an upper end adapted for connection to a length of coiled tubing whereby the locator may be moved within the pipe string in response to movement of the coiled tubing, sai

[ What is claimed is:] [1.]1. A well pipe string joint locator for use in a pipe string, said locator comprising:a housing having an upper end adapted for connection to a length of coiled tubing whereby the locator may be moved within the pipe string in response to movement of the coiled tubing, said housing defining a central opening therethrough and a circulation port in communication with said central opening;a valve disposed in said housing for momentarily opening and closing said circulation port in response to a pressure differential between the coiled tubing and a well annulus outside said housing; andan electronic means disposed in said housing for detecting an increased mass of a pipe joint and generating a momentary electric output signal in response thereto and placing said valve in communication with the pressure in the coiled tubing in response to said signal.