Note: Descriptions are shown in the official language in which they were submitted.
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Lockable core barrel head for drilling system and survey instrument assembly
provided with a
connection link for arrangement in a drilling system
Field of invention
The invention relates to a core barrel head for a wire line operated drilling
system used for
taking core samples of bedrock, as described in the introduction to claim 1.
The invention also relates to a survey instrument assembly provided with a
connection link for
arrangement in a drilling system, as described in the introduction to claim 7.
Especially a survey
instrument assembly provided with a connection link for connection to a
spearhead, drill pipe,
latch assembly, core barrel head or other drilling or geotechnical equipment.
Background
When taking core samples of bedrock using core drilling equipment, knowing
bore hole
trajectory (depth, azimuth and inclination) as well as rotational orientation
of the core sample are
vital information to be able to process the data given by the collected core.
Existing systems for reading the core sample orientation demands that total
length between the
core catcher and latch unit or free space/length inside the inner tube is
reduced to accommodate
the instrumentation.
Existing systems for reading borehole inclination demands that a separate
survey instrument is
lowered inside the drill string by wire.
Object
The main object of the invention is to improve prior art core drilling
technology. More
specifically it is an object to provide a core barrel head, allowing accurate
reading and logging of
the core sample rotational orientation without increasing the total length
between the core
catcher and latch unit or reduce free space/length inside the inner tube.
The invention introduce to the marked a specially designed barrel head that
can be
locked/unlocked in any positions, more specifically locked for axial rotation,
making it possible to
do down hole readings of core sample rotational orientation, as well as the
orientation of other
down hole applications, without increasing the total length between the core
catcher and latch
unit or reduce free space/length inside the inner tube.
A further object of this invention is to allow the recording of borehole and
core sample
inclination, without need of making a separate survey-run.
An object of the invention is to provide a survey instrument assembly provided
with a
connection link arranged for connection to a spearhead or spearhead assembly.
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Another object of the invention is to provide a survey instrument assembly
provided with a
connection link arranged for connection to a drill. pipe, latch assembly, core
barrel head or other
drilling or geotechnical equipment.
The Invention
A core barrel head according to the invention is described in claim 1.
Advantageous features of
the core barrel head according to the invention are described in claims 2 to
6.
A survey instrument assembly according to the invention is described in claim
7. Advantageous
features of the survey instrument are described in claims 8-14.
For performing core drilling there is provided a first aspect of the invention
in the form of a core
barrel head assembly provided with a latch unit equipped with instruments and
mechanisms to
access the inclination and rotational orientation of the core sample.
According to the first aspect there is provided a core barrel head for
connection to a core barrel
and inner tube for collecting core samples, and for connection to a latch
assembly, with a sleeve
for carrying the inner tube. The core barrel head further includes a
controllable locking device
arranged inside the core barrel head for locking the sleeve in a fixed
rotational position relatively
to the latch assembly, to allow measurement of the rotational orientation of
the core samples.
According to the first aspect the locking device is provided with at least one
movable locking
pad, to engage the inner wall of the sleeve.
According to a second aspect of the invention the locking device comprises a
locking element,
which is movable relatively to a radial and/or axial face, to provide a
locking between the sleeve
and a spindle carried by the latch assembly.
According to a third aspect the locking pad(s) is/are arranged tiltable
instead of being rotational
or axially movable.
According to a fourth aspect of the invention the engagement/disengagement of
the locking
device is operated mechanically by the latch unit.
According to a fifth aspect of the invention the engagement/disengagement of
the locking
element is hydraulically operated.
According to a sixth aspect of the invention a survey instrument assembly is
attached at the
upper side of the latch assembly.
For performing core drilling, there is provided a seventh aspect of the
invention in the form of a
survey instrument assembly provided with a connection link at a lower end
arranged for
connection to a spearhead, drill pipe, latch assembly, core barrel head or
other drilling or
geotechnical equipment.
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The connection link is at an upper end provided with means for arrangement to
the survey
instrument assembly, such as a protruding element provided threads.
For connection to a spearhead the connection link is at a lower end of the
body provided with a
quick snap connection adapted for retaining the spearhead.
For connection to a drill pipe, latch assembly, core barrel head or other
drilling or geotechnical
equipment the connection link is at a lower end provided with a radial hole,
via which hole a drill
pipe, latch assembly, core barrel head or other drilling or geotechnical
equipment can be
connected by insertion of a pin in the radial hole.
The survey instrument assembly is at an upper end provided with means, such as
a spearhead
point, for attachment to a wire line or a radial hole for attachment to
suitable means for operating
the survey instrument assembly.
According to an eight aspect of the invention the connection means at the
lower end of the
connection link is a quick-snap connection provided with at claw for
accommodating the
spearhead and secure retaining of this, and for locking axial and rotational
movement of this.
According to a ninth aspect of the invention the claw at the lower end of the
connection link is
provided with at least one claw arm being movable about an axes being offset
from a central axis
of the body.
According to a tenth aspect of the invention claw at the lower end of the
connection link is
provided with two arms being movable about parallel axes being offset from a
central axis of the
body.
According to an eleventh aspect of the invention the claw arms at the lower
end of the
connection link are spring-biased and designed for retaining the spearhead.
Further advantageous features and details of the invention will appear from
the following
example description.
List of Figures
Figure 1 is showing a side view of a drilling assembly for wire line
suspension, with a core barrel
head according to the invention at the lower end,
Figure 2 is showing an axial section of an embodiment of a lockable core
barrel head according
to the invention, for carrying an inner tube (not shown),
Figure 3 is showing a cross section through a further embodiment of a core
barrel head
according to the invention, with an alternative locking means,
Figure 4 show a side view of a survey instrument assembly for wire line
suspension, with a
connection link provided with a quick snap connection according to the
invention at the lower
end,
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Figure 5a is showing a perspective view of a connection link provided with a
quick snap
connection according to the invention,
Figure 5b is showing a cross sectional view of a the connection link in Figure
5a, and
Figure 5c is showing a perspective view of an alternative connection link.
Description of preferred examples
Figure 1 shows at the upper end of a drilling system 10 a spearhead point 11
for attachment to
a wire line during operation, a survey instrument assembly 12 containing the
circuits and units
needed for logging the position of the drilling assembly, including the
inclination and the rotational
orientation of the core samples.
A communication port 13 is arranged at the lower end of the survey instrument
assembly 12.
Following the communication port 13 is a latch assembly 14 with a latch
housing 15 and a pair of
latch elements 16 and 17. The latch elements 16 and 17 are operated by prior
art technology to
lock the drilling head assembly inside the core barrel.
At the lower end of the latch assembly 14 an axial threaded hole indicated at
18 is arranged, for
the upper threaded end 19 of a core barrel head 20 according to the invention.
The core barrel
head 20 is locked with a locking nut 21. Through the threaded hole 18, access
to the interior of the
latch assembly 14 is provided, to get an input for controlling the core barrel
head according to the
invention, as will be described.
Figure 2 shows the core barrel head 20 of Figure 1. Its main parts are a
cylindrical spindle 22
with the treaded end 19 and with an axial bore 23 for a locking bolt 24. The
spindle 22 is carrying a
spindle bushing 25, a trust bearing 26 being arranged between the upper part
of the spindle and
the spindle bushing 25. The spindle bushing 25 is connected to a spindle
sleeve 27 with a threaded
connection 28. At the lower end of the spindle sleeve 27, there is a threaded
bore 29 for carrying
an inner tube collecting core samples. More structural and functional details
of this assembly are
described in the following.
At the upper end of the axial bore 23 of the spindle 22 a slider or piston 30
is arranged. The
piston 30 has a threaded bore 31 to be attached to the upper end of the
locking bolt 24. The upper
end of the piston 30 carries an adjustment screw 32 protruding into the latch
unit 14. The
adjustment screw 32 and thus the locking bolt 24 are operated from the latch
unit 14.
The locking bolt 24 is extending through the bore 23 in the spindle 22, and
into a bore 33 in the
spindle sleeve 27. In the bore 33 a hub 34 is arranged. The hub 34 is carried
by the lower end of
the spindle 22 and is having a central axial bore 35 for the locking bolt 24.
In two opposing radial
slots 36, 37, two locking pads 38, 39 are arranged. The inner end of the
locking pads 38, 39 are
engaging a conical neck 40 on the locking bolt 24 with a ball 41 as
connection.
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When the locking bolt 24 is not engaged by the latch unit, it is lifted to an
upper position by a
screw spring 42 under the piston 30. In this position, the conical neck 40
will expand the locking
pads 38, 39 into engagement with splines 43 in the surrounding bore and thus
lock the sleeve 27 in
relation to the spindle. The locking is facilitated by mating splines on the
free end of the locking
5 pads 38, 39 engaged with splines 43 on the surrounding wall of the bore 33.
When the locking bolt 24 is engaged by the latch assembly 14, the locking pads
38, 39 are
withdrawn from the splines 43. In this position, the spindle bushing 25 and
the spindle sleeve 27
are allowed to rotate freely.
In Figure 3 an alternative embodiment of the invention is shown, with a core
barrel head
assembly 44 based on a sleeve 45. The lower end of the sleeve 45 is
accommodating a piston 46
and a downward projecting piston rod 47 linked to the sleeve 45 with a cross
pin 48. The piston
rod 47 carries a lower screw spring 49 compressed between the piston 46 and a
stop dish 50
locked with a locking ring 51 to the inner wall of the sleeve 45. The screw
spring 49 will urge the
piston 46 towards an upper position. The purpose of this arrangement will
appear from the
following description.
A stack of four roller bearings 52, 53, 54, 55 is carried by a spindle 56. The
spindle 56 is
protruding at the upper end of the core barrel head 44. The top of the spindle
56 is provided with
a flange 57 and a crossing hole 58. The purpose of these parts is to connect
the spindle 56 to the
latch unit of Figure 1.
The spindle 56 is at the lower end carrying a cylindrical nut 59 provided with
a friction dish 60
facing the upper end of the piston 46. The cylindrical nut 59 is fixed in an
end position of the
spindle 56.
An upper screw spring 61 is arranged behind the nut 59 for allowing the sleeve
45 to move
forward between the spindle 56 and sleeve 45 when the pull force exceeds a
certain load.
Under the force of the lower screw spring 49, the upper end of the piston46 is
pressed against
the friction dish 60 attached to the cylindrical nut 59. The faces of the
elements involved in the
frictional locking may be suitably errated.
The wall of the sleeve 45 has two openings 62, 63 for access of drilling
fluid. When under
pressure, the drilling fluid will act upon the piston 46 and urge it downward,
releasing the
frictional locking of the sleeve 45. When the piston 46 is engaged, the sleeve
45 will be free to
rotate independently of the latch unit.
Alternative locking mechanisms
The hub 34 of Figure 2 may have alternative embodiments. Any locking means
which can be
operated by mechanical or hydraulic pressure may be utilized. The locking pads
38, 39 may be
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replaced by a ring of compressible, expandable material being expandable by
the force from a
screw spring and releasable by hydraulic fluid.
The locking pads 38, 39 may be arranged tiltable instead of being rotational
or axially movable.
The piston 30 may also be operated by restricting the waterflow, thus building
up a pressure
inside the latch unit 14.
The spindle 56 of Figure 3 may have a longitudinal bore, corresponding to bore
23, extending
throughout the spindle and through the friction dish 60. In an alternative
embodiment, the
longitudinal bore may accommodate a locking bolt corresponding to the locking
bolt 24 of the
embodiment in Figure 2. The latch unit may engage this locking bolt to depress
the piston 46. This
will be an alternative way of unlocking of the friction means.
Novel survey instrument assembly
Reference is now made to Figures 4 which shows a survey instrument assembly 12
provided
with a spearhead point 11 for attachment to a wire line during operation. The
survey instrument
assembly 12 may also be provided with other suitable means replacing the
spearhead point for
operation of the survey instrument assembly 12. A survey instrument assembly
12 contains
circuits and units needed for logging the position of a drilling assembly,
including the inclination
and the rotational orientation of core samples or other geotechnical
instruments. A
communication port 13 is arranged at the lower end of the survey instrument
assembly 12.
A survey instrument assembly 12 according to the invention further includes a
connection link
70 arranged for connection to a spearhead point 11 or spearhead assembly, as
shown in Figures
5a-b, or to a drill pipe, latch assembly, core barrel head or other drilling
or geotechnical equipment
as shown in Figure 5c.
Reference is now made to Figures 5a-b which show details of a connection link
70 arranged for
connection to a spearhead 11. The connection link 70 is formed by a mainly
elongated body 71
which at its upper end is provided with means for connection to the survey
instrument assembly
12, such as a protruding element 72 provided with threads 73 adapted to a
threaded hole at the
lower end of the survey assembly 12. At a lower end of the body 71 the
connection link 70 is
provided with means for accommodating and retaining the spearhead point 11,
preferably in the
form of a quick snap connection. A quick snap connection is, for example,
provided by means of a
claw 74 arranged for accommodating and secure retaining of the spearhead point
11, and for
locking the axial and rotational movement of this. In the example there is
shown a claw 74
including two claw arms 75 which are movable about two parallel axes 76 being
offset from the
central axis of the body 71. The claw arms 75 are preferably spring-biased and
designed for
retaining the spearhead point 11, and for locking the axial and rotational
movement of this.
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Reference is now made to Figure Sc which shows details of a connection link 70
adapted for
connection to a drill pipe, latch assembly 14, core barrel head 20 or other
drilling or geotechnical
equipment. The connection link 70 is here formed by a solid mainly elongated
body 71 which at its
upper end is provided with means for connection to the survey instrument
assembly 12, such as a
protruding element 72 provided with threads 73 adapted to a threaded hole
provided at a lower
end of the survey assembly 12. At a lower end of the solid body 71 the
connection link 70 is
provided with connection means adapted to connection means of a drill pipe,
latch assembly 14,
core barrel head 20 or other drilling or geotechnical equipment for connection
thereto. The
connection means are in the shown example a radial hole 77 for insertion of a
pin for secure
connection to corresponding holes in a drill pipe, latch assembly, core barrel
head 20 or other
drilling or geotechnical equipment.
By using a survey instrument assembly 12 provided with a connection link 70 as
described
above it will be possible to always have the survey instrument assembly 12
close to the drilling
assembly, which is preferable for the accuracy of the drilling operation.
By use of a survey instrument assembly 12 provided with a connection link 70
according to the
invention the drill operation will become more rapid, due to the number of
separate survey runs
are reduced, as well as one will have better control of bore hole trajectory
by continuous logging
of bore hole trajectory. In other words the survey instrument assembly 12
provided with a
connection link 70 according to the invention provides MWD - Measure while
Drilling - operation.
The above described connection link 70 may be used with the core barrel head
20 or without
the core barrel head 20.
Modifications
The survey instrument assembly provided with a connection link may be provided
with other
drilling equipment, such as packers or wedges, or geotechnical instruments.
The claw of the connection link can include only one claw arm if the body is
adapted with means
for accommodating and retaining the spearhead, and for locked axial and
rotational movement of
this
The means for connection of the survey instrument assembly to the connection
link may be
adapted to other suitable connection means.
The means for connection of a drill pipe, latch assembly, core barrel head or
other drilling or
geotechnical equipment to the connection link may be adapted to other suitable
connection
means.
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List of reference numerals
drilling head assembly
11 spearhead point
12 survey instrument assembly
5 13 communication port assembly
14 latch assembly
latch housing
16, 17 latch elements
18 hole in latch assembly
10 19 threaded end
core barrel head
21 locking nut
22 spindle
23 axial bore
15 24 locking bolt
spindle bushing
26 thrust bearing
27 spindle sleeve
28 threaded connection
20 29 threaded bore
piston
31 threaded bore
32 adjustment screw
33 bore in the spindle sleeve
25 34 hub
axial bore
36, 37 slots for locking pads
38, 39 locking pads
conical neck
30 41 ball
42 screw spring
43 splines
44 core barrel head assembly
sleeve
35 46 piston
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47 piston rod
48 cross pin
49 lower screw spring
50 stop dish
51 locking ring
52-55 roller bearings
56 spindle
57 flange
58 crossing hole
60 friction dish
61 upper screw spring
62, 63 openings
70 connection link
71 body
72 protruding element
73 threads
74 claw
75 claw arms
76 parallel axes
77 radial hole
