Ditch Witch JT30AT - Manual (Page 122)

JT30 /JT30 All Terrain Operator’s Manual
Conduct a Bore - 122
Backream
CMW
Backream
Sometimes it is necessary to drill a pilot hole first, then enlarge the hole to accommodate larger product.
As a general rule, the final hole should be 1.5 times larger than the diameter of the product being installed.
The number of passes needed depends on soil conditions. Do not try to increase hole size too much in one
pass. Several passes using successively larger reamers will save wear on machine.
Moving tools will kill or injure. Shut off drill string power when anyone can
be struck by moving or thrown tools. Never use pipe wrenches on drill string.
Jobsite hazards could cause death or serious injury. Use
correct equipment and work methods. Use and maintain proper safety
equipment.
To help avoid injury: Continue to use strike system during backreaming.
Turning shaft will kill you or crush arm or leg. Stay away.
To help avoid injury:
• Maintain two-way communication with tracker operator.
• Begin backream only when tracker operator has communicated that everyone is clear of the
exposed backream string.
• Do not allow anyone to stand to the side of the exposed drill string. Drill string and backreamer can
move sideways suddenly if rotated while away from the exit hole.