Motor Integrated Reamer

Abstract

In one aspect, an apparatus for use in a wellbore is disclosed that in one non-limiting embodiment may include a drive system coupled to a drill bit by a drive sub for drilling a wellbore, wherein the drive system has an associated bend for directional drilling of the wellbore, and a reamer driven by the drive sub, wherein the reamer reams a ledge formed at a transition from a larger diameter wellbore to a smaller diameter of the wellbore during directional drilling of the wellbore.

1 . An apparatus for use in a wellbore, comprising:
 a drive system coupled to a drill bit by a drive sub for drilling a wellbore, wherein the apparatus includes an associated bend for directional drilling of the wellbore; and   a reamer driven by the drive sub, wherein the reamer reams a ledge formed at a transition from a larger diameter wellbore to a smaller diameter of the wellbore during directional drilling of the wellbore.   
     
     
         2 . The apparatus of  claim 1  further comprising a reamer drive coupled to the drive sub that rotates the reamer as the drive sub rotates. 
     
     
         3 . The apparatus of  claim 2  further comprising a bearing section on the drive sub and wherein the reamer drive is placed on the bearing section. 
     
     
         4 . The apparatus of  claim 2 , wherein the reamer drive comprises:
 a first gear wheel coupled to the drive sub, wherein the first gear wheel rotates when the drive sub rotates; and   a second gear wheel coupled to the first gear wheel and the reamer, wherein the second gear wheel rotates when the first gear wheel rotates to cause the reamer to rotate.   
     
     
         5 . The apparatus of  claim 4 , wherein rotational speed of the reamer is defined at least in part by sizes of the first gear wheel and the second gear wheel. 
     
     
         6 . The apparatus of  claim 1  further comprising:
 a stabilizing device uphole of the reamer; and 
 wherein outside diameter of the reamer is equal to or less than outside diameter of the stabilizing device and less than outside diameter of the drill bit. 
 
     
     
         7 . The apparatus of  claim 4 , wherein the reamer drive contains seals separating the pressure level inside the bearing assembly from the pressure level inside the annulus between the reamer and the wellbore. 
     
     
         8 . The apparatus of  claim 4 , wherein the second gear is in a sealed housing with a lubricant therein. 
     
     
         9 . The apparatus of  claim 1 , wherein the drive system includes one of: a drilling motor and a turbine. 
     
     
         10 . The apparatus of  claim 4 , wherein the second gear wheel is placed inside a housing that is sealed to the inside of the bearing assembly and includes at least one mud port to allow passage of a coolant through the bearing assembly. 
     
     
         11 . The apparatus of  claim 10  further comprising additional seals to generate an encapsulated cavity for the gear wheels to contain a lubricant to provide lubrication to the reamer drive. 
     
     
         12 . A drilling system for directional drilling of a wellbore, comprising;
 a drilling assembly conveyable by a rotatable conveying member, wherein the drilling assembly includes:   a drive system coupled to a drill bit by a drive sub for drilling a wellbore, wherein the drilling assembly has an associated bend for directional drilling of the wellbore; and   a reamer driven by the drive sub, wherein the reamer reams a ledge formed at a transition from a larger diameter wellbore to a smaller diameter of the wellbore during directional drilling of the wellbore.   
     
     
         13 . The drilling system of  claim 12  further comprising a reamer drive coupled to the drive sub that rotates the reamer as the drive sub rotates. 
     
     
         14 . The drilling system of  claim 13 , wherein the reamer drive comprises:
 a first gear wheel coupled to a drive sub, wherein the first gear wheel rotates when the drive shaft rotates; and   a second gear wheel coupled to the first gear wheel and the reamer, wherein the second gear wheel rotates when the first gear wheel rotates to cause the reamer to rotate.   
     
     
         15 . The drilling system of  claim 12  further comprising a sensor for providing measurements relating to a property of interest during drilling of the wellbore. 
     
     
         16 . The drilling system of  claim 12 , wherein the drive system includes one of a motor and a turbine. 
     
     
         17 . A method of drilling a wellbore, the method comprising:
 conveying a drilling assembly by a rotatable conveying member into a wellbore, the drilling assembly including a drive system coupled to a drill bit, an associated bend, and a reamer downhole of the stabilizing device;   drilling the wellbore by rotating the drill bit with the rotatable conveying member and the drive system to form a first section having a first size; and   drilling the wellbore by rotating the drill bit by only the drive system to form a second section of the wellbore, wherein transition from the first section to the second section includes a ledge; and   utilizing the reamer to reduce the ledge to form the wellbore.   
     
     
         18 . The method of  claim 17  further comprising determining one or more downhole parameters of interest during drilling of the wellbore and utilizing the determined one or more parameters of interest to form a deviated wellbore. 
     
     
         19 . The method of  claim 17 , wherein the drilling assembly includes a stabilizing device and the outside diameter of the reamer is equal to or less than the outside diameter of the stabilizing device and less than the outside diameter of the drill bit. 
     
     
         20 . The method of  claim 17 , wherein the reamer is driven by a reamer drive that includes:
 a first gear wheel coupled to the drive sub, wherein the first gear wheel rotates when the drive sub rotates; and   a second gear wheel coupled to the first gear wheel and the reamer, wherein the second gear wheel rotates when the first gear wheel rotates to cause the reamer to rotate.