Page 346 - Air and Gas Drilling Manual

d
3
D =
3
12
D = 0 552 ft Chapter 8: Air, Gas, and Unstable Foam Drilling 8-29
.
3
The total length of the lumped drill pipe body increment (third), H 3, in the
openhole section of the annulus is
2 500 
H 3 = 2 500 − 1 5 .  , 30 
,

H 3 = 2 375 ft
,
The inside diameter of the openhole along this length of the openhole section of the
annulus is
.
d = 7 875 inches
h
d
D = h
h
12
D = 0 656. ft
h
and the outside diameter of the drill pipe body along this length is
D = 0 375 ft
.
2
The total length of the lumped drill pipe tool joints increment (fourth), H 4, in
the openhole section of the annulus is
2 500 
H = 15 .  ,
4  30 

H = 125 ft
4
The inside diameter of the openhole along this length of the openhole section of the
annulus is
D = 0 656. ft
h
and the outside diameter of the drill pipe tool joints along this length is
D = 0 552 ft
.
3