Apparatus and method for communicating information between a wellbore and surface

Abstract

A system, tool and method of communicating data between a wellbore and the surface are provided that include the features of transmitting data from a number of tools in the wellbore to the surface at a first data rate via a communication link in a tubing that supplies fluid under pressure, detecting occurrence of a fault relating to the data communication link is below a threshold, and switching transmission of least some of the data from the tools by generating pressure pulses through the fluid in the tubing at a second data rate that is lower than the first data rate.

1 . A method of communicating data between a wellbore and the surface, comprising:
 transmitting data from at least one tool in the wellbore to the surface at a first data rate via a communication link in a tubing that supplies fluid to the wellbore;   detecting occurrence of a fault relating to the data communication link; and   switching transmission of at least some of the data from the at least one tool from the data communication link to a mud pulse telemetry unit that sends the at least some of the data by generating pressure pulses through in the fluid in the tubing at a second data.   
   
   
       2 . The method of  claim 1  further comprising:
 sending command signals to the at least one tool to send data in a manner that is compatible with transmitting the data at the second data rate.   
   
   
       3 . The method of  claim 1 , wherein the data communication link is one of an electrical wire and an optical fiber. 
   
   
       4 . The method of  claim 1  further comprising continuing to transmit data from the at least one tool via the data communication link. 
   
   
       5 . The method of  claim 1  further comprising ceasing to transmit the at least some of the data by the mud pulse telemetry unit when the fault has been corrected. 
   
   
       6 . The method of  claim 1  further comprising activating a pulser downhole to generate the pressure pulses upon detecting the fault. 
   
   
       7 . The method of  claim 6 , wherein the at least one tool comprises a plurality of tools and wherein the method further comprises controlling flow of data from each of the plurality of tools to the data communication link and the pulser. 
   
   
       8 . The method of  claim 7  further comprising controlling flow of data from a particular tool in the plurality of tools to the data communication link and the pulser when the particular tool exhibits a malfunction. 
   
   
       9 . The method of  claim 1 , wherein the data communication link is selected from a group consisting of: (i) an electrical conductor; (ii) an optical fiber; and (iii) a conductor that contains nano carbon tubes aligned along the length of the conductor. 
   
   
       10 . A wellbore telemetry system, comprising:
 a drill string in a wellbore having a tubing that carries a data communication link and supplies fluid under pressure during drilling of the wellbore;   a drilling assembly at a bottom end of the tubing, the drilling assembly carrying a plurality of tools;   a first data transmission device that transmits data received from each tool in the plurality of tools during drilling of the wellbore to the surface via the data communication link at a first data rate;   a downhole pulser that is configured to send data to the surface by producing pressure pulses in the fluid at a second data rate that is lower than the first data rate; and   a control circuit that activates the downhole pulser to transmit at least some of the data from the plurality of tools at the second data rate when a fault is detected with the data communication link.   
   
   
       11 . The wellbore telemetry system of  claim 10 , wherein the control circuit sends a command to each tool in the plurality of tools to send data at a rate that is compatible with transmission of the data by the pulser. 
   
   
       12 . The wellbore telemetry system of  claim 10 , wherein the downhole pulser is one of a: (i) poppet-type pulser; (ii) rotary pulser; (iii) a piezoelectric device; (ix) magnetostrictive device. 
   
   
       13 . The wellbore telemetry system of  claim 10 , wherein the control circuit comprises a processor that utilizes a program to determine when a particular tool is performing below a set standard and in response thereto controls flow of the data from the particular tool for transmission to the surface. 
   
   
       14 . The wellbore telemetry system of  claim 10  further comprising an interface circuit that receives the data from the control circuit and transfers the received data to the data communication link. 
   
   
       15 . The wellbore telemetry system of  claim 14 , wherein the data communication link is selected from a group consisting of: (i) an electrical conductor; (ii) a fiber optic link; (iii) a link that includes carbon nano-particles. 
   
   
       16 . The wellbore telemetry system of  claim 10  further comprising a surface telemetry unit that is configured to activate when the control circuit activates the downhole pulser to start sending surface signals in the form of pressure pulses through the fluid. 
   
   
       17 . The wellbore telemetry system of  claim 16  further comprising a detector in the drilling assembly that detects pressure pulses received downhole that relate to the surface signals and generates electrical signals responsive to the detected pressure pulses. 
   
   
       18 . The wellbore telemetry system of  claim 17  further comprising a processor that processes the electrical signals generated by the detector to ascertain the surface signals. 
   
   
       19 . The wellbore telemetry system of  claim 10 , wherein the control circuit includes a processor and a data storage device and wherein the processor establishes a two-way data communication between the drilling assembly and the surface via the fluid when the fault is detected with the data communication link. 
   
   
       20 . A drilling assembly for use during drilling of a wellbore, comprising:
 a data connection configured to connect to a data communication link carried by a tubing that supplies fluid under pressure to the downhole assembly during drilling of the wellbore;   a plurality of tools in the drilling assembly, wherein each tool provides data to be transmitted to a surface location during drilling of the wellbore;   a first data transmission device that transmits data received from each tool in the plurality of tools during drilling of the wellbore to the data communication link via the data connection at a first data rate;   a downhole pulser that is configured to produce pressure pulses in the fluid at a second data rate that is lower than the first data rate during drilling of the wellbore; and   a control circuit configured to control the downhole pulser to transmit data from each tool in the plurality of tools at the second data rate when a fault is detected with the data communication link during drilling of the wellbore.   
   
   
       21 . The drilling assembly of  claim 20  further comprising an interface circuit that is configured to transfer data between the control circuit and the data communication link. 
   
   
       22 . The drilling assembly of  claim 21 , wherein the control circuit includes a processor that is programmed to stop sending data from the tools to the interface circuit when the control circuit activates the pulser. 
   
   
       23 . The drilling assembly of  claim 20 , wherein the control circuit comprises a processor and a program, wherein the processor determines performance of at least one tool in the plurality of tools during the drilling of the wellbore and controls flow of data to the communication link and the pulser when the determined performance is below a threshold. 
   
   
       24 . A method of communicating data between a wellbore and the surface, comprising:
 transmitting data between at least one tool in the wellbore and the surface at a first data rate via a first wired-communication link;   detecting occurrence of a fault relating to the wired-data communication link; and   switching transmission of at least some of the data between the at least one tool and the surface from the data wired-communication link to a second telemetry unit that sends data at a second data rate that is lower than the first data rate.   
   
   
       25 . The method of  claim 24 , wherein the second telemetry unit transmits data using one of electromagnetic signals and acoustic signals.