Kick detection system and method for drilling well and associated well drilling system

Abstract

A kick detection system for drilling a well including an ultrasonic module for transmitting signals to a returning drilling fluid from the well, and receiving corresponding backscatter signals; and a process apparatus for obtaining a flow characteristic of the returning drilling fluid based on the backscatter signals, and detecting a kick based on the flow characteristic of the returning drilling fluid and drilling related data. A well drilling system including a drilling string for guiding a drilling bit and a drilling fluid to a well; a conduit defining a channel for accommodating the drilling string and a returning drilling fluid from the well; and the kick detection system. A kick detection method is also described.

What is claimed is: 
     
         1 . A kick detection system for drilling a well, comprising:
 an ultrasonic module for transmitting signals to a returning drilling fluid from the well, and receiving corresponding backscatter signals; and   a process apparatus for obtaining a flow characteristic of the returning drilling fluid based on the backscatter signals, and detecting a kick based on the flow characteristic of the returning drilling fluid and drilling related data.   
     
     
         2 . The kick detection system of  claim 1 , wherein a first portion of the drilling related data comprises a pump stroke number or backscatter signals obtained by transmitting signals to a drilling fluid flowing to the well, the process apparatus obtains the flow characteristic of the drilling fluid flowing to the well based on the first portion of the drilling related data, and detects the kick based on a change of difference between the flow characteristic of the drilling fluid flowing to the well and the flow characteristic of the returning drilling fluid. 
     
     
         3 . The kick detection system of  claim 2 , wherein the process apparatus detects the kick based on the change of difference and a second portion of the drilling related data comprising operation data relating to a drilling operation, fluid characteristic data, or a combination thereof. 
     
     
         4 . The kick detection system of  claim 1 , wherein the process apparatus determines a flow change of the returning drilling fluid based on the backscatter signals and detects the kick based on the flow change, when the drilling related data indicate any of a trip in mode, a trip out mode, a flow check mode, and a normal drilling mode. 
     
     
         5 . The kick detection system of  claim 1 , wherein the process apparatus comprises a first process module below the sea surface and a second process module above the sea surface. 
     
     
         6 . The kick detection system of  claim 5 , comprising: a communicating apparatus for transmitting information between the first process module and the second process module. 
     
     
         7 . The kick detection system of  claim 1 , comprising: a warning apparatus for providing a warning to an operator when a kick is detected. 
     
     
         8 . The kick detection system of  claim 1 , comprising: a displaying apparatus for displaying the flow characteristic, the drilling related data, a kick warning or any combination thereof. 
     
     
         9 . A well drilling system, comprising:
 a drilling string for guiding a drilling bit and a drilling fluid to a well;   a conduit defining a channel for accommodating the drilling string and a returning drilling fluid from the well; and   a kick detection system comprising an ultrasonic module for transmitting signals to a returning drilling fluid from the well, and receiving corresponding backscatter signals; and a process apparatus for obtaining a flow characteristic of the returning drilling fluid based on the backscatter signals, and detecting a kick based on the flow characteristic of the returning drilling fluid and drilling related data.   
     
     
         10 . The well drilling system of  claim 9 , wherein the ultrasonic module comprises a plurality of ultrasonic sensors disposed on the conduit. 
     
     
         11 . The well drilling system of  claim 9 , wherein the conduit comprises a barrier for isolating the ultrasonic module from the returning drilling fluid. 
     
     
         12 . The well drilling system of  claim 9 , wherein the conduit comprises:
 a riser; and   a spool connected to the riser for disposing and isolating the ultrasonic module and providing a working environment for the ultrasonic module.   
     
     
         13 . The well drilling system of  claim 9 , comprising: a blowout preventer stack for operating to prevent the kick according to an instruction from the process apparatus. 
     
     
         14 . A kick detection method for drilling a well, comprising:
 transmitting signals to a returning drilling fluid from the well, and receiving corresponding backscatter signals;   obtaining a flow characteristic of the returning drilling fluid based on the backscatter signals; and   detecting a kick based on the flow characteristic of the returning drilling fluid and drilling related data.   
     
     
         15 . The kick detection method of  claim 14 , wherein a first portion of the drilling related data comprises a pump stroke number or backscatter signals obtained by transmitting signals to the drilling fluid flowing to the well, and detecting the kick comprises:
 obtaining the flow characteristic of the drilling fluid flowing to the well based on the first portion of the drilling related data; and   detecting the kick based on a change of difference between the flow characteristic of the drilling fluid flowing to the well and the flow characteristic of the returning drilling fluid.   
     
     
         16 . The kick detection method of  claim 15 , wherein detecting the kick comprises: detecting the kick based on the change of difference and a second portion of the drilling related data comprising operation data relating to a drilling operation, fluid characteristic data, or a combination thereof. 
     
     
         17 . The kick detection method of  claim 14 , wherein detecting the kick comprises: determining a flow change of the returning drilling fluid based on the backscatter signals and detecting the kick based on the flow change, when the drilling related data indicate any of a trip in mode, a trip out mode, a flow check mode, and a normal drilling mode. 
     
     
         18 . The kick detection method of  claim 14 , comprising: operating a blowout preventer stack to prevent the kick. 
     
     
         19 . The kick detection method of  claim 14 , comprising: providing a warning to an operator when a kick is detected. 
     
     
         20 . The kick detection method of  claim 14 , comprising: displaying the flow characteristic, the drilling related data, a kick warning or any combination thereof.