Page 15 - Drilling a Straight Hole
P. 15
DRILLING A STRAIGHT HOLE
Petroleum Extension-The University of Texas at Austin
stabilizers and, 50 drawworks, 26, 26f
crossovers, 68, 69f drift. See also deviation
crow’s foot, 94 deviation-recording instruments and, 92
cutter(s) factors affecting, 9, 9f
for roller reamers, 84, 84f MWD and, 99
vibration dampeners and, 52 dril graf monitors/dril data, 89f
drillability of formations, variation in, 25, 31
daily drilling reports, 34, 34f
deflection, 24 drill collar(s), 55f. See also spiral drill collars; square
derrick, drill pipe and, 26, 26f drill collars; standard drill collars
annular clearance and, 48
derrick strength, 47 bore, 61
deviation, 1. See also drift drill strings and, 26, 26f
bottom of hole and, 9 HWDP and, 48–49
drilling contracts and, 91 inside diameter (ID), 47t, 48
deviation clauses. See contract deviation clauses moments of inertia and, 47, 47t
deviation-recording instruments, 91–99. See also outside diameter (OD), 47t, 48
go-devil packed pendulum assembly and, 55, 55f
about, 91–92, 99 relative deflection of, 48, 48f
pendulum effect and, 95 spirals/grooves on, 78
time required and, 92 stiffness of, 47
types of, 95–99 transition zone and, 48
deviation-recording tools. See wellbore survey tools undersized, 27
deviation surveys, 33 drill collar string(s). See also drill string(s)
differential pressure, 56 BHA and, 48
differential sticking, 77–78, 77f stuck pipe and, 21
dip angle, 9 drilling assembly
direction. See azimuth in drilling report, 34, 34f
directional drilling transitional, 69f
drill string and, 2 drilling contract(s)
most advanced system, 6 crooked holes and, 1
vertical trajectory and, 10
DLS. See dogleg severity (DLS) deviation clause in, 3, 7–10, 8f
dogleg(s) hole deviation and, 6, 92
casings and, 20 specifications and, 11
defined, 16, 21 drilling fluid(s)
fatigue damage and, 18 downhole motors and, 59
Grade-E drill pipe and, 18, 19, 19f fatigue damage and, 18
problems, 21–22 drilling mud, 71
reduced WOB and, 7, 7f, 59 drilling rate, doglegs and, 7
restricted rate of hole-angle change and, 15–16, 15f drill pipe(s). See also heavy-walled drill pipe (HWDP)
restricted total hole angle and, 14, 14f dogleg limits and, 18, 19f
severe, 20 doglegs, keyseats and, 21–22
severity records and, 8, 16 heavyweight, 69f
usable borehole and, 12 safety factor and, 73
dogleg severity (DLS), 8 stands of, 26
dolomite, 25f, 83 stuck/risk of sticking, 20, 92
double recorder, 96, 97f drill pipe failure, 17–19
downhole deviation, 1 dogleg limits/Grade-E drill pipe and, 18, 19f
downhole drilling motors, 9, 35 fatigue failure and, 17–18, 17f
downhole mud motor, 6, 56–58 drill pipe float, 95
bent housings and, 36, 36f drill stem tools, 61, 90
drill string and, 35, 35f drill string(s). See also drill collar string(s)
rotor and, 56, 56f, 57f directional drilling and, 2
stator and, 56, 57f, 58f downhole mud motors and, 35
downhole positive pulse instrument, 88, 88f drill collars and, 26, 26f
drag, 17, 20 drilling mud and, 71
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