Note: Descriptions are shown in the official language in which they were submitted.
CA 02844869 2014-03-05
RUBBER ELEMENT REMOVAL TOOL
Field of the Invention
The disclosed relates generally to the fields of oil and gas drilling rigs and
down hole
pressure control tools and, more specifically, to tools and methods for
removing the
rubber elements of a rotary control device for repair or replacement.
Description of Related Art
Most drilling rigs are required to utilize pressure control tools such as
rotary control
devices (RCDs) to help prevent down hole blowouts. Located on the inside of an
RCD
is a rubber element or seal. During drilling, wear and tear causes these
rubber
elements to wear out very quickly, requiring frequent replacement. The
currently
practiced methods to remove an RCD rubber element are archaic and dangerous.
Heavy chains are attached and brute force is applied. As the rubber element
releases
(sometimes requiring up to 60,000 pounds of pressure to release a 250-4500
pound
rubber element), it swings free on the chains with great force, causing the
extremely
heavy rubber element to reel around chaotically and dangerously.
Because the rubber elements in an RCD actually seal a tremendous amount of
down
hole pressure, they are subject to a great deal of abrasion and wear.
Consequently,
they must be replaced regularly.
There is therefore a need for a device and method to safely and more easily
remove
rubber elements of an RCD or related down hole tool for repair or replacement.
Summary of the Invention
In accordance with the present disclosure, a device and method is disclosed
for
safely and more easily pulling a rubber element of an RCD from a drill stem.
An objective of the disclosure is a device and method to, in a controlled
manner, pull
1
81778133
an RCD rubber element from a drill stem.
An objective of the disclosure is a device and method to reduce the dangers
associated
with removing a rubber element of an RCD from a drill stem.
An objective of the disclosure is a device and method to shorten the time
required to
remove an RCD rubber element from a drill stem.
An objective of the disclosure is a device and method for removing seals or
rubber
elements from pressure control tools.
An objective of the disclosure is a tool for removing a rubber element of a
rotary control
device (RCD) from a drill stem, the tool comprising an upper pulling ring of a
circumference sufficient to traverse around the rubber element of an RCD, the
ring
having an open position and a closed position; a lower stabilizing ring of a
circumference
sufficient to traverse around a drill pipe stump, the ring having an open
position and a
closed position; a plurality of chains suspending the lower stabilizing ring
vertically below
the upper pulling ring, and a hoist connection above the top of the upper
ring.
An objective for removing a rubber element of a rotary control device (RCD)
from a drill
stem, the method comprising: opening an upper pulling ring and placing it
around the
rubber element; opening a lower stabilizing ring and placing it around a drill
pipe stump,
the lower ring being suspended vertically from the upper ring by a plurality
of chains;
connecting a hoist to a hoist connection; lifting the drill stem until the
chains tighten and
the drill stem is pulled up through the rubber element, leaving the rubber
element free.
An objective for removing a rubber element of an RCD from a drill stem wherein
both the
upper pulling ring and the lower stabilizing ring comprise two jaws, each jaw
having a fist
end and a second end, wherein the first ends are fixedly hinged together and
the second
ends hold the jaws in a closed position by a removable pin.
Other advantages of the present invention will become apparent from the
following
descriptions, taken in connection with the accompanying figures, wherein, by
way of
illustration and example, an embodiment of the present invention is disclosed.
2
Date Recue/Date Received 2020-06-26
CA 02844869 2014-03-05
Brief Description of the Drawings
The figures constitute a part of this specification and include exemplary
embodiments to the invention, which may be embodied in various forms. It is to
be
understood that in some instances various aspects of the invention may be
shown
exaggerated or enlarged to facilitate an understanding of the invention. To
enable
more thorough understanding of the features and advantages of the present
invention, reference is now made to the detailed description of the invention
along
with the accompanying figures in which:
FIG. 1 depicts the upper ring (closed position) of a removal tool in
accordance with a
preferred embodiment of the disclosed device and method.
FIG. 2 depicts the upper ring (open position) of a removal tool in accordance
with a
preferred embodiment of the disclosed device and method.
FIG. 3 depicts the holding feet of the upper ring in accordance with a
preferred
embodiment of the disclosed device and method.
FIG. 4 depicts the removal tool device in accordance with a preferred
embodiment of
the disclosed device and method.
FIG. 5 depicts the removal tool device in accordance with a preferred
embodiment of
the disclosed device and method.
Detailed Description of the Preferred Embodiments
Detailed descriptions of the preferred embodiment are provided herein. It is
to be
understood, however, that the present invention may be embodied in various
forms.
Therefore, specific details disclosed herein are not to be interpreted as
limiting, but
rather as a basis for the claims and as a representative basis for teaching
one skilled
in the art to employ the present invention in virtually any appropriately
detailed
system, structure or manner.
3
CA 02844869 2014-03-05
The disclosed is a device and method for safely and more easily removing the
rubber
element of an RCD from the drill stem. Because the disclosed method and device
incorporates both stabilizing and bracing features, it utilizes principles of
leverage. As
a result, the rubber element is pulled far more quickly and with far more
control
than when using traditionally known methods. The controlled pull and release
makes
the entire process far safer to employ.
Turning to the figures for illustrative purposes, FIG. 1 depicts an upper
pulling ring 10
of the disclosed RCD rubber element removal tool in a closed position, secured
around the rubber element 12. This view discloses that the ring 10 is
comprised of a
first jaw 14 and a second jaw 16, each jaw having a first end 18 and a second
end 20.
The first ends of each jaw are fixedly hinged to each other by a hinge 22
capable of
allowing a limited range of motion to enable the jaws to open and close. It is
preferable to keep grease on the hinges to improve functionality. The second
end 20
of the first jaw 14 culminates in a female end of a connection piece 24. The
second
end 20 of the second jaw 16 culminates in a male end of the connection piece
24.
Both second ends have a through hole. When the two ends are connected, the
through holes, not seen here, line up vertically and a removable primary pin
26 may
be inserted all the way through all of the through holes to hold the jaws of
the ring in
a closed position. When the pin 26 is removed, the second ends 20 of the jaws
of the
ring are pulled open, causing the ring to assume its open position.
The primary pin 26 is, in a preferred embodiment, steel, although other
similarly
rigid, strong and durable materials could be used provided they met the
objectives
described herein.
Viewable in FIG. 1 are the holding feet 30 of the upper ring 10. The holding
feet are
not required for all models. Due to the fact that RCDs vary in their
construction, the
holding feet are of great use when removing the rubber element on certain
models
of RCDs and not necessary in removal of other models. In a preferred
embodiment,
the holding feet 30 have a beveled edge retaining lip 32 that hooks under the
flange
ring 34 of the rubber element 12. Affixed to a bottom edge of each of the
holding
feet 30 is a chain clevis 36 holding the first loop 38 of a chain 40 which
vertically
4
CA 02844869 2014-03-05
descends to a lower stabilizing ring.
FIG. 1 discloses two eye brackets 42 each having an eye through which
traverses
each end of a chain sling 44 which ascends vertically, enabling a rig operator
to hold
the tool and the rubber element using a hoist or other lifting or holding
means. The
chain sling 44 is used herein as the hoist connector, although other means of
connecting a hoist to the tool could be appropriate, including but not limited
to
beams, tongs, hoist rings and chain hoists.
FIG. 2 discloses a view of the upper pulling ring 10 in its open position,
showing in
more detail the open and close functionality of the upper ring 10, which is
what
enables it to open around the rubber element 12 and then close tightly on the
rubber element 12. The first end 18 or female end, of the first jaw 14 has an
inner
groove 46 into which inserts the first end 18 of the second jaw 16, or male
end. Both
ends have a through hole 48 that lines up when first end 18 of the second jaw
16 is
inserted into the inner groove 46 of the first end 18 of the first jaw 14. A
primary pin
26 is inserted vertically all the way through all the through holes 48,
holding the two
ends together such that the jaws are closed and the entire upper ring is in a
closed
position. Although not shown in this view, the lower stabilizing ring is of
the same
components and construction as the upper pulling ring, although it is of
substantially
smaller circumference and lacks the holding feet 22. Once the pin 26 is
removed, the
two first ends of the jaws are pulled apart and the opposing hinge 22 of the
second
ends swivels, enabling the ring to be in its open position.
A safety pin 50 is also shown which may be used in conjunction with the
primary pin
26. The primary pin 26 has a flat stop washer 52 that further has, on one
side, a
rounded notch 54. The safety pin 50 traverses through this notch 54 and
continues
downward through a secondary hole 56 that is adjacent to the through hole 48.
The
safety pin has a push-button top, which, when depressed, retracts a small ball
on
each side of the lower portion of the safety pin, causing it to be able to be
removed
from the secondary hole 56. When the pin 50 is inserted into the secondary
hole 56
and the push-button top is released, the small on each side of the lower
portion of
the safety pin protrude, locking the safety pin 50 in place and, concurrently,
holding
the primary pin 26 in place as well.
CA 02844869 2014-03-05
FIG. 3 discloses, in more detail, one of the holding feet 30 of the upper ring
10
showing how the beveled edge retaining lip 32 hooks at the flange ring 34 of
the
rubber element 12 and further showing the clevis 36 and the chain 40
vertically
descending.
FIG. 4 reveals the entire RCD rubber element removal tool 60, revealing how
the
upper pulling ring 10 and lower stabilizing ring 62 are connected by a
plurality of
vertical chains 40, the chains suspending the lower ring from the upper ring.
Also
shown is the chain sling 44 ascending vertically above the upper pulling ring.
FIG. 5 reveals the same view as FIG. 4 however with the tool 60 in place on
the drill
stem 70. The upper ring 10 is shown closed tightly around the rubber element
12 and
the lower ring 62 is closed tightly around the drill pipe stump 64. The lower
ring 62
attaches to the drill pipe stump 64 under the upset and drill collar 66. The
circumference of the upper ring can be changed to fit any size rotary control
device
"rubber element" and the lower ring size can be changed to fit any size drill
pipe. The
chain sling 44 allows the rig operator to lift, control, and move and position
the tool
60 using a hoist or other similar means. Pictured in FIG. 5 is the drill stem
70 which is
ultimately pulled vertically up through the rubber element 12 as shown by the
directional arrows 76. The threaded end 72 of the drill stem 70 is shown
disconnected from the drill pipe 74. The drill pipe travels vertically
downward into
the ground and is extremely heavy. The lower ring 62 being affixed around the
drill
pipe stump 64, therefore creates a great deal of stability and leverage for
the tool
60.
In operation, the tool is used in the following manner to remove seals or
rubber
elements from pressure control tools such as RCDs. The upper ring 10 opens by
removing the primary pin 26 and, if necessary, the safety pin 50, allowing the
jaws to
open, as the hinge 22 opposite the primary pin 26 allows the jaws to swivel.
Once
open, the upper ring 10 can be placed around the rubber element 12. Although
in
the illustrations, the upper ring is shown around the top of the rubber
element, in
some RCD models, the ring may be more appropriately placed around a different
aspect of the rubber element, such as the middle. As the upper ring 10 is
lowered
6
CA 02844869 2014-03-05
onto the rubber element 12, the beveled edge 32 of the holding feet 30 hit the
flange ring 34 located on the outside circumference of the rubber element 12.
This
allows the upper ring 10 to open slightly and then close once the flange ring
34 is
inside the beveled edge 32. Once the ring 10 is closed, the primary 26 and the
safety
pins 50 are both inserted through the through holes 48. The holding feet 30
serve as
a holding device once the rubber element 12 is removed. The feet 30 hold the
rubber
element 12 against the underside of the upper ring 10. This allows the rig
operator to
control and lower the rubber element 12 after it is freed from the drill stem
70.
The lower ring 62 opens by removing a primary pin 26 and the safety pin 50 (if
applicable) and pulling the jaws apart, in the same fashion as the way the
upper ring
opens. Again, the jaws are able to open due to the hinge that is opposite from
the
pins. Once open, the lower ring is placed around the drill stem and the hinged
jaws
are closed and the primary pin and safety pin are inserted through the through
holes. The lower ring does not have holding feet.
Once both upper 10 and lower rings 62 are closed and the pins are inserted the
rig
operator can begin to lift the drill stem 70 and rubber element 12. As the
drill stem
70 and rubber element 12 are lifted, the upper side of the lower ring 62 hangs
on the
upset of the drill pipe stump 64 causing the lower ring 62 to remain
stationary. The
plurality of chains 40 suspending the lower ring 62 vertically from the upper
ring 10
begin to tighten. At this point the rig operator tightens the chain sling 44
that is
above the upper pulling ring 10. Once all the chains are tight, the chain
sling 44 being
held by the hoist, the rig operator then begins lifting the drill stem 70. As
the rig
operator continues to pull upward, the drill stem 70 begins to slide up
through the
now stationary rubber element 12. The tool 60 and the rubber element 12 remain
stationary because the lower ring 62 is closed on the drill pipe stump 64. The
rubber
element 12 begins to slip off the bottom of the drill stem 70, as the drill
stem 70 is
lifted upward through the rubber element 12. When the drill stem 70 is
released, the
weight of the tool 60 and the rubber element 12 are left hanging free of the
drill
stem 70 by the hoist or other lifting device.
Once the rubber element is released, the tool and the rubber element are
lowered
by releasing tension on the plurality of chains vertically suspending the
lower
7
CA 02844869 2014-03-05
stabilizing ring from the upper pulling ring. The lower ring is then opened by
removing the primary pin and safety pin and pulling apart the jaws which
swivel
open on the hinge that is opposite of the pins. The tool is lowered to the
ground and
the upper pulling ring is opened by removing the primary pin and the safety
pin and
pulling apart the jaws which swivel open on the hinge that is opposite of the
pins.
The rubber element is then released from the upper pulling ring.
Although holding feet are described herein with regard to the design, other
bracing
means may be appropriate for use with other brands and types of RCDs. In the
preferred embodiment, the general structure of the tool will remain
consistent,
however, specially designed custom jigs may be affixed onto the upper pulling
ring
for use with specific RCD models, depending on the shape and structure of the
RCD,
provided the same objectives are met as described herein, namely that the
upper
pulling ring stays securely affixed to the rubber element.
While the invention has been described in connection with a preferred
embodiment,
it is not intended to limit the scope of the invention to the particular form
set forth,
but on the contrary, it is intended to cover such alternatives, modifications,
and
equivalents as may be included within the spirit and scope of the invention as
defined by the appended claims.
It is to be understood that the embodiments disclosed herein are shown for
illustrative purposes and are not intended to be construed as limitations of
the
disclosed method and system. Those skilled in the art will recognize or be
able to
ascertain in the course of routine experimentation, that variations and
equivalents of
the embodiments may be undertaken without departing from the scope of the
invention.
Certain terms are used throughout the description to refer to particular
method
components. As one skilled in the art will appreciate, design and
manufacturing
companies may refer to a component by different names. This document does not
intend to distinguish between components that differ in name but not function.
8
CA 02844869 2014-03-05
The terms "including" and "comprising" are used in an open-ended fashion, and
thus
should be interpreted to mean "including, but not limited to ... "Also, the
term
"couple" or "couples" is intended to mean either an indirect or direct
connection.
Thus, if a first device couples to a second device, that connection may be
through a
direct connection or through an indirect connection via other intermediate
devices
and connections. Moreover, the term "method" means "one or more components"
combined together. Thus, a method can comprise an "entire method" or "sub
methods" within the method.
The use of the word "a" or "an" when used in conjunction with the word
"comprising" may mean "one", or may also mean "one or more." The use of the
term
"or" in the claims is used to mean "and/or" unless explicitly indicated to
refer to
alternatives only or the alternatives are mutually exclusive, although the
disclosures
supports a definition that refers to only alternatives and "and/or."
The methods and systems disclosed and claimed herein can be made and executed
without undue experimentation based on the level of disclosure presented.
While
the methods and systems have been described in terms of their preferred
embodiments, it will be apparent to those skilled in the art that they are not
limited
to the exact steps described and may vary from such description without
departing
from the scope and spirit of the invention. The substitutes and modifications
employed by one skilled in the art are deemed to fall within the scope of the
invention.
9
