DO
OWNHOLE DRILLING
D
MOTOR
M
WIT
TH REAMER
R SECTION
This publication discloses the co
oncept of including a rea
amer section as part of a drilling mottor.
ng the reame
er section on
n the housing of the drill ing motor, th
he bit will rottate at a spe
eed
By placin
equal to the drilling motor
m
rotor RPM
R
plus the
e drill string RPM, while the reamer section will
rotate at the drill strin
ng RPM. Som
me of the po
otential bene
efits of imple
ementing thiss concept arre as
follows:
R
RP
PM and angu
ular velocity of the outer diameter off the bit, lead
ding to less w
wear
1.) Reducing
on the bit face
e
R
in torque fluctu
uations
2.) Reduction
3.) Flexibility in the final hole
e size by usin
ng different d
amers; ream
mers may be
diameter rea
nterchangeable
in
4.) Same
S
Bottom
m Hole Assem
mbly can be
e used to drilll several secctions with tthe use or
re
emoval of the reamer.
A mid-rea
amer may also be applie
ed to improv
ve stability a nd effective hole openin
ng.
Represe
entative Figu
ures
NOV 60.3118 Publiccation D
Date Published
d: August 22,, 2011 © 20111 National O
Oilwell Varco, All rights reserved Disclaimer: This publication is for in
nformation pu
urposes and ddoes not neceessarily repreesent productts or services o
offered by Nattional Oilwelll Varco.