Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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AUTONOMOUS DRILLING MACHINE FOR THE CONSTRUCTION OF
SERVICE SHAFTS AND OPEN SHAFTS
Purpose of the Invention
The invention is an autonomous drilling machine for the construction of
service
shafts and free face, also known as "slots", which is specially designed to
improve the
efficiency of mine production and civil engineering projects, it also
considerably reduces
the interaction between men and machines, thus reducing the risks inherent in
underground
drilling and other operations compared with conventional shaft construction
methods.
Background of the Invention
The dimensions of the slot shafts or free face normally used in mines vary
from 1,2
m to 2,1 m in diameter, more usually 2,1 m and from 20 m to 20 m long at
inclinations of
around 900 to 45 from the horizontal.
The shaft and free face drilling machine was originally designed to drill mine
ventilation shafts, among other applications, and can drill holes 2,1 m in
diameter and
between 20 and 200 m long; the construction process takes around 4 to 8 weeks.
Drilling
service and free face "slots" produces a very stable and smooth surface, thus
reducing
post-drilling work considerably. Traditionally, the drilling process required
the
construction of a concrete bearing slab for the machine about 3mx4mx 0,4 m
thick, to
which the machine was secured by anchor bolts, usually 0,222 m diameter by 1,2
m. It also
requires a structural base of beams and high-strength structural steel to
support the machine
when the drilling has been completed; machines of this type consist of a power
unit,
electrical control unit and separate control console, which implies connecting
hoses and
electric cables 5 to 7 m long, depending on the working area, making it
difficult to move
the machine and all of its components to the different working faces; moving
requires the
use of a loading shovel and leads to the loss of more than 15% of reaming time
in the mine.
In order to optimise drilling time and increase productivity in the drilling
of service
Date Recue/Date Received 2022-09-21
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shafts and free face in different mines, an autonomous machine has been
designed and
built, in which the drilling rig has its own propulsion system, preferably but
not necessarily
a crawler tractor powered by an internal combustion engine, which should
preferably be
located at the rear, controlled by fixed control points located preferably at
the rear of the
tracked unit. Once on site the machine is fully self-aligning with respect to
the shaft to be
drilled, taking into account that the axis of the shaft should coincide with
the central shaft
of the reduction gearbox in the mechanical transmission, which provides
variable rotation
speed and constant torque adjusted to suit the material to be drilled. This
machines has two
angle levels and fixed control of alignment and anchoring; firstly the crawler
tractor is
levelled using hydraulic jacks and then the drilling angle is controlled using
the two
inclination cylinders (08) and the machine is connected by two support columns
(29);
finally, the machine is anchored to both the ground, using the lower hydraulic
jacks, and
the roof of the gallery using the upper jacks; in this way neither anchor
bolts nor a concrete
slab are needed. The service and free face shaft drilling rig has its power
unit and electrical
control cabinet incorporated into the rig propulsion system, which is
preferably a crawler
tractor and therefore it is not necessary to connect or disconnect hydraulic
hoses or electric
cables between the machine's component parts during installation and
withdrawal from the
site. Consequently, transport and erection times are considerably reduced,
eliminating
much dead time and enabling 20 m to 200 m to be drilled in 3 to 4 weeks, thus
achieving
85% efficiency per shaft. The risks inherent in the transport and drilling
process are also
reduced, as is environmental pollution caused by hydraulic oil spillages
during connecting
and disconnecting the hoses.
Previous descriptions cover inventions in the same field as this one, thus US
document 4.147.215 describes a land-based drilling rig with a mast, a mobile
carriage
mounted on the mast and moving generally up and down the length of the mast; a
rotary
table mounted on the carriage to turn the drill string, an improved method of
joining and
detaching the drill pipe sections including: clamps to hold the first section
of drill pipe;
sliding grips mounted on the machine to hold the second section of drill pipe
and support
the drill string. The clamps are power operated to break the connection
between the first
and second sections of the drill string the clamps hold the first section of
drill pipe and the
Date Recue/Date Received 2022-09-21
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rotary table turns to tighten or release the joint between the drill pipe
sections. The drilling
derrick is also provided with means for removing the drill pipe from the well.
Document WO 2014133445 describes the raise-boring method of drilling shafts
using a machine with a pivot system enabling the drill head to operate at a
transverse angle
to the machine.
The document TUMI RAISE BORING:"SBM 400 SR, SLOT RAISE", describes
a service shaft and free face drilling rig consisting of: a mechanical
reduction gearbox to
which the drill pipes are attached by a positioning arm and decoupling clamps;
two sets of
cylinders to move the drill head on the guide columns during the drilling
operation;
hydraulic jacks to secure the machine on site, before the start of drilling
operations at the
different angles of which the machine is capable; outer and lower support
jacks.
Summary of the Invention
The drilling machine in this invention is self-propelled within the mine,
propulsion
consisting preferably but not exclusively of a crawler tractor driven by an
internal
combustion engine with controls located preferably at the left rear side of
the crawler unit,
which positions and levels the machine with respect to the shaft to be
drilled, and two
guide columns (26) to maintain the direction of the shaft being drilled
throughout its length
and upon which slides the reduction gearbox (04); the ends of these guide
columns (26)
are fixed to the base of the structure (27) and an upper structure (31)
respectively, taking
into account that the axis of the shaft must coincide with the central shaft
of the reduction
gearbox (04) and/or transmission system that provides two alternative speeds:
high (50 to
70 RPM) and low (12 to 14 RPM) using a mechanical geared transmission (04) and
a
hydrostatic motor to increase and reduce reaming speed. This improvement
provides better
stability during reaming and provides variable rotation speed but constant
torque according
to the conditions of the terrain. For this the machine enables variable angles
with fixed
levelling and anchoring. The crawler tractor is levelled first using the
hydraulic jacks and
then the drilling angle is set using the gradient cylinders (08), finally the
machine is
Date Recue/Date Received 2022-09-21
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anchored to the floor and roof of the gallery using the lower and upper jacks,
without the
need for bolts or a concrete slab.
Autonomous low-profile drilling rig for the construction of service shafts and
free
face, enabling drilling at different angles, either longitudinal or
transversal, relative to the
machine, in which the drilling rig is propelled by a crawler tractor and the
structural base
(27) is connected to the crawler tractor (28) by a system that enables the
machine to pivot
to the desired drilling angle. Two lateral hydraulic cylinders (18), 1,27 m
(5") in diameter
and one cylinder 1,78 m (7") in diameter, designed to work at a pressure of at
least 34.473.8
kPa (5000 PSI) in service, enabling the drilling head (32) to move along the
guide columns
(26) during drilling of the pilot hole and reaming. The hydraulic jacks (09)
and (10) secure
the machine in the working position to the floor and roof of the gallery,
creating greater
stability during reaming and reducing vibration; these jacks extend from 5,08
to 15,24 m
(20 to 60") depending on the size of the gallery and the angle of the machine
and are fitted
with a device that improves their grip on the ground. The lower (07) and
exterior (29) jacks
stabilise and offset the longitudinal gradient of irregular terrain; the
tilting cylinder (08)
enables the machine to incline at different angles using devises secured to
the guide
columns, to give the required working angle.
This drilling rig for service shafts and free faces can drill holes 2,1 m in
diameter
and around 200 m long that are commonly required in different types of mines,
at angles
from 90 to 45 with respect to the longitudinal axis of the machine and from
90 to 45
with respect to the transverse axis in both directions (left and right) by
means of a pivot
system that enables the machine to incline and secures it, thus allowing
drilling in small
spaces where manoeuvrability is restricted. The construction of a shaft using
the
autonomous drilling rig described here requires approximately 4 days to drill
a 20 m hole
2,1 m in diameter, and the result is a very stable and homogeneous shaft with
a good finish.
One of the main advantages of using an autonomous machine for drilling service
shafts
and free faces is a significant reduction in interaction between man and
machine by using
remote control for the drill pipe handling aim and the electro-hydraulic
mechanism for
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connecting and disconnecting the drill rod sections. From an economic point of
view there
is an increase in productivity in comparison with the previous design.
Brief Description of the Drawings
Figure 1 is a right-hand side view of the machine in transport mode.
Figure 2 is a left-hand side view of the machine in operating mode.
Figure 3 is a front view in operating mode.
Detailed Description of the Invention
Figure 1 shows the shaft and slot drilling rig in the transport position. The
crawler
tractor (01), internal combustion engine (02), fixed controls (03), remote
operating controls
(34) controls for transport (35) when the rig is being moved, are all shown.
Component
(06) is the fixed control unit that operates the four levelling jacks (07) on
the crawler tractor
(01). The rig is anchored by two lower hydraulic jacks (09) on both ends of
each support
column (29) and on the front of the rig, the bases of which are bolted to the
structural base
(27) of the rig, as well as upper hydraulic jacks (10) secured to the roof of
the gallery.
The electrical control panel (11) and power unit (20) are also integrated into
the crawler
tractor (01) and provide the hydraulic power necessary to operate the machine,
and are
located at the rear of the rig. The drill rod handling arm (15) adds and
removes the drill
rod sections. Two sets of lateral hydraulic cylinders (18) are fitted to the
sides of the rig
and transmit the vertical load generated by the pilot bore and reaming
process; each set of
cylinders (18) is secured by pins to the structural base and the inverted
cylinder (27)
transmits the hydraulic power to the reduction gearbox (04) through a thrust
device (30),
thus generating the reaming force necessary. The sets of cylinder (18) possess
six cylinders
of 1,27 m (5") and 1,78 m (7") in diameter respectively, providing the
necessary 34.473.8
KPa (5000 PSI) of force for the reaming process, divided into two sets of
three (18), each
consisting of two cylinders 1,27 m (5") on either side of an inverted cylinder
of 1,78 m
(7"), positioned at the sides of the machine to transmit the vertical force
necessary for pilot
hole drilling and reaming. The hydraulic oil tank (22) contains the oil
necessary to operate
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the crawler tractor (01) while hydraulic oil tank (23) contains oil for the
power unit (20).
Figure 2 shows a profile view of the drilling rig in the operating position at
an
inclination of approximately 45 to the transverse axis of the machine, with
the lower
anchors extended tot he ground; the angle is adjusted by the control (05) on
one side of the
gear case. The mechanical reduction gearbox (04), which transmits torque from
the
hydrostatic motor (25) is in the upper position, enabling installation of a
section of drill
rod (16) by the handling arm (15).
Figure 3 shows a front view of the machine in operating mode, showing it
slewed
approximately 45 to the left with respect to its transverse axis; it can slew
to either side
once the machine is in the operating position; the lower and outer jacks are
extended to the
ground in order to stabilise the machine during operation.
In a preferred use of the invenmtion, to operate the machines there is a
removable
control console (12) and remote control unit (34) hung around the operator's
neck. The
drilling method consists basically of 2 stages, pilot hole drilling and
reaming. The pilot
hole is drilled downwards using a 2,79 m (11") diameter pilot bit and a series
of drill pipes
2,54 m (10") in diameter by 1,50 m long (16), depending on the depth of the
shaft. Drilling
can also be carried out at different angles to either the longitudinal or
transverse axis of
the machine, normally between 90 and 45 , depending on the requirements of
condition
of the rock. The mine must provide a 3-phase, 60 Hz, AC electricity supply at
440 volts
producing 350 kVA, and an average of 30,3 to 37,91/min (8 to 10 gals/min) of
clean water
for removing the detritus, connected to the machine by a rotating coupling
(14). The
machine includes a drill rod handling arm (15) operated electro-hydraulically
to load each
drill rod section in the rig's drill head (32) in a safe and efficient manner.
The machine
includes an electro-hydraulic clamp (17) to tighten the DI-22 threaded
connections of the
mechanical transmission and drill string, located on its base. The mechanical
transmission
consists of various reduction gears and a hydrostatic motor (25) that provide
constant
torque and the ability to adjust the rotation speed of the drill string
according to the
conditions of the rock.
Date Recue/Date Received 2022-09-21
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The drilling rig described here weighs less than 16 metric tonnes and has a
power
output of less than 150 kW; it is designed to operate in galleries that are
preferably less
than 3,8 m high, for which reason it is referred to as a low-profile machine;
for transport
purposes its dimensions are less than 2,5 m in height by 2,3 m wide, meaning
that it will
enter a standard shipping container. For that reason its hydraulic cylinders
(18) work in
tandem, so that the reduction gearbox (04) can be lifted sufficiently to
install a drill pipe
section (16) and completely withdraw all the cylinder sets on completion of
the reaming
operation to achieve its transport height. Each set of cylinders (18) include
an internal
check valve, one on each side of the machine, allowing the reduction gearbox
to be lowered
very slowly in the event of a hydraulic oil leak; this valve is normally
closed and placed
between the high-pressure line and the tank and its purpose is to limit the
pressure to a
given value and divert all the oil flow from the pump to the tank.
The hydraulic force and torque to turn the drill string enable the machine to
reach
the lower target level in both stages of this method of boring. When the pilot
hole has been
drilled the second or raise boring stage begins. The bit and adjacent section
of drill rod
(16) is uncoupled in the mine in order to attach the reamer. The machine uses
the reamer
to increase the diameter of the shaft by raise boring, during which the drill
pipes (16) are
withdrawn. Both the lower clamp on the base of the machine (17) and the upper
clamp
(19) on the drilling head (32) are used to uncouple each section of the drill
string. The
hydraulic clamp on the drilling head (32) is operated by two hydraulic
cylinders (33)
which open and close the clamp, enabling the drill pipe sections to be
uncoupled, thus
reducing man-machine interaction and the time taken to uncouple the drill
pipes. Both
clamps are operated electro-hydraulically, thus eliminating human contact with
the
machine.
Date Recue/Date Received 2022-09-21
