Gathering Site Information - Toro 4045 Operator's Manual

4. Drill the bore.
You drill the bore in 3 stages:
A. Entry
In the entry phase of the bore, you push the drill
bit and head into the ground at an angle of up to
16 degrees. After pushing in one or more pipes,
you begin drilling down and forward until you
reach the desired depth or depth-gauge hole (if
used).
B. Horizontal Reach
After reaching the desired depth, you push the
bit forward, steering the bit to a horizontal depth.
The drill bit emits a radio signal from the sonde
housing, which allows a crew member on the
surface to track the location and depth of the head
using the sonde receiver as you drill and steer it
along a planned route.
C. Exit
Once you have attained the planned horizontal
reach, you steer the head up at an angle similar
to your entry angle bringing the bit into the exit
hole or trench.
Refer to Drilling the Bore (page
5. Backream the bore and pull back cabling or pipe.
After entering the exit hole, the end crew detaches the
drill bit and sonde housing from the drill pipe. In its
place, they attach a reaming bit and the end of the cable
or pipe to be pulled through the bore. The reaming
bit is designed to enlarge the bore as you pull it back.
As before, you pump drilling fluid through the pipe
to the reaming bit as you pull the cable or pipe back
through the bore to lubricate the reamer and allow
the cable or pipe to slide easily through the bore. You
continue pulling the pipe back until the reamer reaches
the depth-gauge hole or exits at the entry point. There
you remove the reamer and product from the drill pipe,
pulling the pipe the rest of the way back to the machine.
Refer to Backreaming and Pullback (page 72)
instructions on backreaming and pulling cable or pipe.
6. Finish the bore and leave the job site.
After completing the operation, you need to disconnect
and clean the machine and load it on the trailer; refer to
Cleaning with the Spray-hose Attachment (page
68).
for
114).
48

Gathering Site Information

Planning the Initial Route
Before you can begin boring, you need to plan the route that
you will bore and prepare as follows:
•
Create a basic plan for the bore, mapping out the
proposed route.
– Note any obstacles which may affect the bore, such
as large trees, bodies of water, buildings, etc.
– Plan the route of the bore to avoid as many obstacles
as possible.
– Determine the depth of any bodies of water to be
crossed to ensure that you can get deep enough under
them.
•
Determine the depth that you need to install the material
at and the minimum bend radius both of the drill pipe
and of the material being installed. This will seriously
affect how long the bore needs to be and at what angle
that you can begin and end; refer to
Path (page 51).
•
Have the area of the bore marked for utility lines (in the
US call 811). Ensure that all lines are marked on your
blueprints/bore plan as well.
•
Contact the local authorities to arrange for any permits
and traffic control that you will need to conduct the job.
Inspecting the Proposed Job Site
Physically inspect the site as follows:
•
Note the terrain, slopes, valleys, hills, and any features
not planned for previously.
Determine the degree of slope at both the proposed entry
point and exit point.
•
Determine what the soil types are in the area and, if
possible, at the depth that you will be boring. You may
need to dig test holes at intervals along the bore path to
fully determine this.
•
Walk the area of the bore, looking for any possible
unmarked obstructions. Look for manholes, pedestals,
old foundations, etc.
•
Identify all the hazards that you will pass within 3 m (10
ft).
Planning the Bore