Well-drilling pipe

Claim 1

A WELL-DRILLING PIPE STRING COMPRISING A PLURALITY OF SUBSTANTIALLY EQUAL-DIAMETER PIPE SECTIONS DISPOSED WITH COMMUNICATING CENTRAL BORES IN END-TO-END ABUTTING RELATIONSHIP, A FIRST CONNECTOR SECURED TO ONE END OF EACH PIPE SECTION AND PROJECTING RADIALLY THEREFROM, SAID FIRST CONNECTOR BEING PROVIDED IN ITS PROJECTING PART WITH AN AXIALLY EXTENDING THROUGHGOING CHANNEL ISOLATED FROM THE CENTRAL BORE OF ITS PIPE SECTION, A SECOND CONNECTOR SECURED TO THE OPPOSITE END OF EACH PIPE SECTION AND PROJECTING RADIALLY THEREFROM, SAID CONNECTORS BEING PROVIDED WITH COMPLEMENTARY SCREW THREADS MATINGLY ENGAGING EACH OTHER AT ABUTTING ENDS OF ADJOINING PIPE SECTIONS FOR HOLDING THE LATTER TOGETHER, SAID SECOND CONNECTOR EXTENDING AXIALLY BEYOND ITS PIPE SECTION AND HAVING A RECESSED INNER WALL AT THE LEVEL OF SAID ABUTTING ENDS WHEREBY A CLEARANCE BRIDGING SAID ENDS IS FORMED, AND CONDUIT MEANS HELD IN POSITION ALONGSIDE EACH PIPE SECTION BY THE TWO CONNECTORS THEREOF, SAID CONDUIT MEANS EXTENDING FROM SAID RECESS TO SAID CHANNEL AND COMMUNICATING THEREWITH FOR ESTABLISHING A CONTINUOUS FLOW PATH INDEPENDENT OF SAID CENTRAL BORES ALONGSIDE SAID PIPE SECTIONS.