Ditch Witch JT40, Operator'S Manual

Page: 137 / 253

Conduct a Bore - 136
JT40/JT40 All Terrain Operator’s Manual
Correct Direction
Correct Direction
Correcting direction is a skill operators gain with experience and knowledge of equipment and soil
conditions. These instructions cover only basic procedures. For information about specific equipment or
jobsites, contact your Ditch Witch
®
dealer.
To track progress and make corrections, one crew member locates the drill head and sends instructions to
the operator. Corrections are made by tracking the drill head, comparing current position to bore plan, and
steering drill head as needed.
Basic Rules
General
• Steering ability depends on soil condition; bit, drill head, and nozzle used; roll of drill head; and
distance pushed without outer rotation.
• All corrections should be made as gradually as possible. See “Recommended Bend Limits” on
page 92.
• Over correcting will cause “snaking.” This can damage pipe and will make drilling and pullback more
difficult. Begin to straighten out of each correction as early as possible.
JT Mode
• Do not push an entire piece of drill pipe into ground without rotation. This can exceed bend radius and
cause pipe failure.
AT Mode
• Steering in rock is slower than steering in other soil conditions. Be patient.
• Inner rod is rotating at all times when AT mode is selected and inner rotation switch is on.
• Stop outer rotation and engage spindle brake when making directional changes.
• Depth estimate and pitch accuracy improve if drill head is at 3 o’clock when reading is taken.
• Pull back 6” (152 mm) of pipe before checking pitch.