Wired pipe surface sub

Abstract

A sub for a wired pipe system that includes a body includes an outer surface and a pin end and a first transmission device located in or near the pin end. The sub also includes a communication collar that at least partially surrounds the outer surface and that is rotatable relative to the body, a second transmission device in electrical communication with the first transmission device and a transmission line that electrically connects the first and second communication devices and that passes at least partially through the body. The sub further includes a third transmission device located in the communication collar in communication with the second transmission device. In the disclosed sub, the first, second and third transmission devices are all of the same type.

What is claimed is: 
     
         1 . A sub for a wired pipe system, the sub comprising:
 a body including an outer surface that defines an inner bore through which a fluid passes during drilling;   a first transmission device ( 34 ) located within the outer surface and at an end of the body and outside of the inner bore such that the fluid passes through the first transmission device during drilling;   a communication collar that at least partially surrounds the outer surface and that is rotatable relative to the body;   a second transmission device in electrical communication with the first transmission device and located on the outer surface of the body;   a transmission line that electrically connects the first and second transmission devices and that passes at least partially through the body; and   a third transmission device located in the communication collar in communication with the second transmission device;   wherein the first, second and third transmission devices are all of the same type,   wherein, in operation, signals are received from or provided to a surface unit from the communication collar through a communication line.   
     
     
         2 . The sub of  claim 1 , wherein the first, second and third transmission devices are all selected from one of: a capacitive coupler, and a resonant coupler. 
     
     
         3 . The sub of  claim 1 , further comprising:
 a wireless transmitter in electrical communication with the third transmission device.   
     
     
         4 . The sub of  claim 1 , further comprising:
 an outer adapter coupled to the outer surface that contains the second transmission device.   
     
     
         5 . The sub of  claim 4 , wherein the outer adapter rotates relative to the communication collar. 
     
     
         6 . The sub of  claim 1 , wherein the communication collar includes a collar body and an output terminal. 
     
     
         7 . The sub of  claim 6 , wherein the collar body includes a communication line that carries signals between the third transmission devices and the output terminal. 
     
     
         8 . The sub of  claim 7 , wherein the output terminal includes a wireless transmitter. 
     
     
         9 . The sub of  claim 8 , wherein the communication collar includes:
 a retaining ring that surrounds the outer surface; and   a first bearing disposed about the outer surface and held in place at least partially by the retaining ring.   
     
     
         10 . The sub of  claim 9 , further wherein the communication collar further includes a second bearing;
 wherein the collar body is at least partially disposed between the first and second bearings.   
     
     
         11 . The sub of  claim 10 , further comprising: an outer adapter at least partially disposed between the first and second bearings.