BAKER HUGHES - Drilling Fluids Reference Manual

HYDRAULICS
Figure 9 - 11 Well Schematic
1. Find fluid velocity in drillpipe, drill collars, and annulus:
• Drillpipe
( 375)
2
( 3.826)
0.408Q
0.408
V p
= = = 10.45 ft /sec
2
D
• Drill collars
( 375)
( 2.8125)
0.408
V p
= = 19.34 ft /sec
2
• Annulus of drill collar and open hole
V
0.408Q
a = ----------------------------------- =
(D 2 ) 2 – ( D
2 1 )
• Annulus of drillpipe and open hole
V
0.408( 375 )
a = ------------------------------- = 1.98 ft/sec
9.875 2 – 4.5 2
• Annulus of drillpipe and casing
----------------------------------
0.408( 375 ) = 3.40 ft/ sec
9.875 2 – 7.25 2
BAKER HUGHES DRILLING FLUIDS
REFERENCE MANUAL
REVISION 2006 9-30