Intelligent Centralizer for Multi-Stage Diameter Reduction

Abstract

An intelligent centralizer for multi-stage diameter reduction includes control, motion execution, and connection modules. The control module comprises a microcontroller unit and a battery pack. The motion execution module comprises a flow channel control execution unit, a stroke control execution unit and a piston extension execution unit. The flow channel control execution unit comprises a controller, a shunt, a thrust ball bearing, an end cover, a drive shaft, a magnetic coupler, a motor protection shell, a motor, and a motor protection housing. The stroke control execution unit comprises a stroke controller, a reset spring and an electromagnet. The piston extension execution unit comprises the screw push block, a piston cover, a fixing bolt, a piston and a check valve. The intelligent centralizer further comprises an upper joint, an upper shell connected thereto through a threaded connection, and a lower shell connected to the upper shell through another threaded connection.

What is claimed is: 
     
         1 . An intelligent centralizer for multi-stage diameter reduction, comprising a control module, a motion execution module and a connection module, wherein:
 the control module comprises a microcontroller unit (MCU) ( 21 ) and a battery pack ( 22 );   the motion execution module comprises a flow channel control execution unit, a stroke control execution unit and a piston extension execution unit;   the flow channel control execution unit comprises a controller ( 3 ), a shunt ( 4 ), a thrust ball bearing ( 14 ), an end cover ( 15 ), a drive shaft ( 16 ), a magnetic coupler ( 17 ), a motor protection shell ( 18 ), a motor ( 19 ), and a motor protection housing ( 20 );   the motor protection shell ( 18 ) and the motor protection housing ( 20 ) include four uniformly distributed cavities through which a drilling fluid enters the controller ( 3 ), and the motor protection shell ( 18 ) and the motor protection housing ( 20 ) are connected by a threaded connection;   the motor ( 19 ) is fixed in or on the motor protection housing ( 20 ) with bolts, the magnetic coupler ( 17 ) and the drive shaft ( 16 ) are connected by 4 first groups of bolts, the end cover ( 15 ) and the controller ( 3 ) are connected by 4 second groups of bolts, and the drive shaft ( 16 ) is fixed in the controller ( 3 );   the drive shaft ( 16 ) has first and second ends with a keyway, and the drive shaft ( 16 ), the magnetic coupler ( 17 ) and the controller ( 3 ) realize circumferential transmission using a key connection;   the controller ( 3 ) includes a lower shell with 3 radial flow channel holes, the shunt ( 4 ) includes 3 flow channel holes corresponding to the controller ( 3 ) or one or more structures therein, and the shunt ( 4 ) has a flow channel therein from radial to axial;   the thrust ball bearing ( 14 ) is between the controller ( 3 ) and the shunt ( 4 ), and the intelligent centralizer further comprises an upper shell ( 2 ) having a shoulder therein configured to position the thrust ball bearing ( 14 ) axially;   the stroke control execution unit comprises a stroke controller ( 9 ), a reset spring ( 10 ) and an electromagnet ( 11 );   the stroke controller ( 9 ) includes three slots or openings with different heights or lengths, and at least one of the slots has a circular hole at an upper end thereof;   the reset spring ( 10 ) is at a lower end of the stroke controller ( 9 ), and each of the stroke controller ( 9 ) and the lower shell ( 6 ) have a shoulder configured to position the reset spring ( 10 ) axially;   when the stroke controller ( 9 ) moves axially, the return spring ( 10 ) compresses or extends;   the intelligent centralizer further comprises a screw push block ( 5 ) and a lower shell ( 6 ), the screw push block ( 5 ) is connected to the stroke controller ( 9 ) by a threaded connection to realize synchronous rotation, the electromagnet ( 11 ) includes a threaded external shell, and the lower shell ( 6 ) includes a threaded hole in which the threaded external shell is fixed;   the piston extension execution unit comprises the screw push block ( 5 ), a piston cover ( 7 ), a fixing bolt ( 8 ), a piston ( 12 ) and a check valve ( 13 );   the spiral push block ( 5 ) has a cylindrical cavity therein and an outer spiral spline comprising a first spiral spline section configured to coordinate with a spiral spline in the lower shell ( 6 ), and a second spiral spline section with a variable thickness that contacts and is configured to extend the piston ( 12 );   the piston cover ( 7 ) is helical and includes three uniformly distributed piston holes and eight threaded holes;   the piston ( 12 ) has a cylindrical section, a cuboid section, and an inclined surface having an inclination consistent with a slope of the outer spline of the screw push block ( 5 ), and the intelligent centralizer further comprises a spring between the piston ( 12 ) and the piston cover ( 7 );   the check valve ( 13 ) includes an external shell having a threaded connector, which is fixed in a threaded hole in of the upper shell ( 2 );   the piston cover ( 7 ) is fixed on the lower shell ( 6 ) through a fixing bolt ( 8 );   the connecting module comprises an upper joint ( 1 ), the upper shell ( 2 ) and the lower shell ( 6 );   the lower shell ( 6 ) includes 3 first spiral grooves or openings, each first spiral groove or opening includes 3 piston holes, and the lower shell ( 6 ) includes 3 second spiral grooves or openings;   the intelligent centralizer further comprises an upper joint ( 1 ), connected to the upper shell ( 2 ) through a first conical threaded connection, and the upper shell ( 2 ) and the lower shell ( 6 ) are connected through a second conical threaded connection.   
     
     
         2 . The intelligent centralizer according to  claim 1 , wherein the magnetic coupler ( 17 ) comprises an outer rotor ( 1701 ), a permanent magnet ( 1702 ), and an inner rotor ( 1703 ); the outer rotor ( 1701 ) and the motor shaft are connected by bolts, the outer rotor ( 1701 ) and the motor shaft are connected by keys; the inner rotor ( 1703 ) and the drive shaft ( 16 ) are connected by bolts, and the inner rotor ( 1703 ) and the drive shaft ( 16 ) are connected by keys. 
     
     
         3 . The intelligent centralizer according to  claim 1 , wherein the controller ( 3 ) and the shunt ( 4 ) are equipped with an O-shaped sealing ring configured to prevent the drilling fluid from penetrating into the thrust ball bearing ( 14 ). 
     
     
         4 . The intelligent centralizer according to  claim 1 , wherein the electromagnet ( 11 ) is retracted or retractable when the electromagnet ( 11 ) is not powered, and when the electromagnet ( 11 ) is powered, the positioning pin extends, spirals with the stroke controller ( 9 ), and enters the circular hole in the at least one slot in the stroke controller ( 9 ) to achieve stroke positioning. 
     
     
         5 . The intelligent centralizer according to  claim 1 , wherein the motor ( 19 ) is a DC motor, and the motor ( 19 ) rotates to drive one or more flow channels in or of the controller ( 3 ) and the shunt ( 4 ), and the drilling fluid enters the flow channels, pushing the screw push block ( 5 ) downward and spirally, and extending or pushing the piston ( 12 ) out; when the piston ( 12 ) is retracted, the screw push block ( 5 ) moves upward, and the drilling fluid in a cavity between the screw push block ( 5 ) and the shunt ( 4 ) passes through the check valve ( 13 ). 
     
     
         6 . The intelligent centralizer according to  claim 1 , a U-shaped screw groove in the screw push block ( 5 ), the slots in the stroke controller ( 9 ), and an inner screw groove of the lower shell ( 6 ) have a same screw angle. 
     
     
         7 . The intelligent centralizer according to  claim 1 , wherein the four first groups of bolts are circumferentially uniform around a central axis of the intelligent centralizer. 
     
     
         8 . The intelligent centralizer according to  claim 1 , wherein the second groups of bolts are circumferentially uniform around a central axis of the intelligent centralizer. 
     
     
         9 . The intelligent centralizer according to  claim 1 , wherein the 3 radial flow channel holes are circumferentially uniform around the. 
     
     
         10 . The intelligent centralizer according to  claim 1 , wherein the 3 flow channel holes of the shunt ( 4 ) correspond to the 3 radial flow channel holes of the lower shell of the controller ( 3 ). 
     
     
         11 . The intelligent centralizer according to  claim 1 , wherein the three slots of the stroke controller ( 9 ) are spiral and have a U shape. 
     
     
         12 . The intelligent centralizer according to  claim 1 , wherein the circular hole has a depth of 8 mm. 
     
     
         13 . The intelligent centralizer according to  claim 1 , comprising three of the electromagnets. 
     
     
         14 . The intelligent centralizer according to  claim 1 , wherein each of the first spiral spline section and the second spiral spline section has three circumferentially uniformly distributed sections. 
     
     
         15 . The intelligent centralizer according to  claim 1 , wherein the piston cover ( 7 ) comprises three cover sections uniformly distributed along a circumference of the piston cover ( 7 ). 
     
     
         16 . The intelligent centralizer according to  claim 1 , comprising nine of the pistons ( 12 ). 
     
     
         17 . The intelligent centralizer according to  claim 1 , wherein the spring is configured to retract the piston. 
     
     
         18 . The intelligent centralizer according to  claim 1 , comprising three of the check valves ( 13 ), evenly distributed along the circumference of the intelligent centralizer. 
     
     
         19 . The intelligent centralizer according to  claim 1 , comprising 24 of the fixing bolts ( 8 ). 
     
     
         20 . The intelligent centralizer according to  claim 5 , wherein when the drilling fluid passes through the check valve ( 13 ), compression and/or pressure of the drilling fluid is reduced, and the screw push block ( 5 ) can be reset.