Prepare - 54
JT520 Operator’s Manual
Plan Bore Path
CMW
Minimum Depth
Because you must bend pipe gradually, entry pitch and
bend limits determine how deep the pipe will be when
it becomes horizontal. This is called the
minimum
depth
.
•
To reduce minimum depth (D1), reduce entry
pitch. This also decreases setback.
•
To increase minimum depth (D2), increase entry
pitch. This also increases setback.
Bore Path Calculator
Entry pitch, setback, and minimum depth work together with bend limits to determine the bore path. To find
the setback (B) and entry pitch (A) that will take you to the desired minimum depth (D), use the chart
below.
Minimum depth (D)
Entry pitch (A)
Setback (B)
Depth to begin steering (S)
2’ 0" (0.6 m)
-18%
17’ 4" (5.3 m)
0’ 11" (0.28 m)
2’ 4" (0.7 m)
-20%
18’ 8" (5.7 m)
1’ 0" (0.30 m)
2’ 9" (0.8 m)
-22%
19’ 11" (6.1 m)
1’ 1" (0.33 m)
3’ 1" (0.9 m)
-24%
21’ 2" (6.5 m)
1’ 2" (0.36 m)
3’ 6" (1.1 m)
-26
22’ 5" (6.8 m)
1’ 3" (0.38 m)
3’ 11" (1.2 m)
-28
23’ 8" (7.2 m)
1’ 4" (0.41 m)
4’ 5" (1.4 m)
-30
24’ 11" (7.6 m)
1’ 5" (0.43 m)
IMPORTANT:
Numbers in table based on
70’ (21.3 m) minimum bend radius
, beacon housing, EZ-
Connect, connector, transition sub, and 1/3 of first drill pipe (L, totaling 5’ [1.5 m]) in the ground before
steering.
Summary of Contents for JT520
Page 1: ...JT520 Issue 1 1 Operator s Manual CMW 053 1219...
Page 59: ...Prepare 58 JT520 Operator s Manual Check Supplies and Prepare Equipment CMW...
Page 63: ...Drive 62 JT520 Operator s Manual Shut Down Unit CMW...
Page 71: ...Transport 70 JT520 Operator s Manual Tow CMW...
Page 113: ...Systems and Equipment 112 JT520 Operator s Manual Drill Pipe CMW...
Page 117: ...Complete the Job 116 JT520 Operator s Manual Stow Tools CMW...
Page 141: ...Service 140 JT520 Operator s Manual As Needed CMW...
Page 145: ...Specifications 144 JT520 Operator s Manual CMW...
Page 148: ......
Page 149: ......
Page 150: ...JT520 Operator s Manual Service Record 149 CMW Service Record Service Performed Date Hours...
Page 151: ...CMW Service Record 150 JT520 Operator s Manual Service Performed Date Hours...