Note: Descriptions are shown in the official language in which they were submitted.
LATERALLY MOVABLE MOBILE WELL SERVICING UNITS AND METHODS OF
USE
TECHNICAL FIELD
[0001] This document relates to laterally movable mobile well servicing
units and
related methods of use.
BACKGROUND
[0002] A well site may locate one or more wells within a complex
arrangement of
equipment, infrastructure, and vehicles. Plural wells are often located on a
pad, which may
be constructed from rig mats, concrete, or other materials. An individual well
at a well site
may require servicing at any stage of operation, for example during
exploration, completion,
production, or abandonment. In a typical well servicing method a tractor unit
backs up a
wheeled trailer until the trailer is located adjacent the well. A platform on
the trailer may
then be raised or lowered to a desired height to permit personnel to access
various sections of
the wellhead assembly as needed for well servicing. The presence of
infrastructure,
equipment, and vehicles may obstruct the path of the trailer to the well,
making it difficult to
maneuver the trailer into the desired position. In some cases plural wells may
require
servicing at a multi-well pad. Plural wells may be serviced using plural
trailers, each
positioned adjacent a respective well. A single trailer may also be used to
service plural
wells one by one in series, starting by positioning the trailer adjacent a
well, servicing the
well, using the tractor unit to reposition the trailer adjacent a subsequent
well, servicing the
subsequent well, and continuing until all wells are serviced as desired.
SUMMARY
[0003] A mobile well service unit is disclosed comprising: a structural
frame with a
front end and a rear end, and defining an axis between the front end and the
rear end; a
platform mounted at the front end or the rear end of the structural frame and
configured to
move up and down relative to the structural frame; and ground engaging members
mounted
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to the structural frame and configured to permit the mobile well service unit
to move
laterally, relative to the axis, across a ground surface.
[0004] A method is disclosed comprising using the mobile well service
unit to
service an oil or gas well.
[0005] A method is disclosed comprising: positioning a mobile well
service unit
adjacent a first oil or gas well, the mobile well service unit comprising a
structural frame
with a platform mounted at an end of the structural frame adjacent to the
first oil or gas well,
the platform configured to move up and down relative to the structural frame;
and moving,
for example translating, the mobile well service unit laterally across a
ground surface from
the first oil or gas well to a second oil or gas well.
[0006] A trailer or skid is disclosed that mounts a platform that can be
raised or
lowered, and that has ground engaging elements (such as tracks or wheels) that
permit
sideways movement of the trailer or skid relative to an axis of the trailer or
skid.
[0007] A trailer or skid is disclosed in which the trailer or skid has
a) first ground
engaging elements (such as wheels for a trailer or beams for a skid) that
mount the platform,
and b) second ground engaging elements that can be steered to drive the
trailer or skid
sideways.
[0008] A trailer or skid is disclosed in which the first ground engaging
elements are
motorized wheels to provide forward/ backward movement, and b) the second
ground
engaging elements are motorized to provide sideways movement, respectively.
[0009] A trailer or skid is disclosed in which the second ground
engaging elements
are outriggers that can lift the first ground engaging elements off of the
ground, and are
motorized to provide sideways movement.
[0010] A trailer or skid is disclosed provided as an oilfield production
well servicing
rig, to permit the rig to move sideways to travel between adjacent wells.
[0011] In various embodiments, there may be included any one or more of
the
following features: The ground engaging members comprise continuous tracks.
The ground
engaging members are configured to move, relative to the structural frame,
between: a raised
stowed position, where the ground engaging members out of contact with the
ground; and a
lowered deployed position, where the ground engaging members contact the
ground surface.
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Each of the ground engaging members comprises an actuator connected to move
the ground
engaging member between the raised stowed position and the lowered deployed
position.
The actuator comprises a hydraulic cylinder. The ground engaging members are a
first set of
ground engaging members, and further comprising: a second set of ground
engaging
members mounted to the structural frame and configured to permit the mobile
well service
unit to move in a direction parallel to the axis. The second set of ground
engaging members
are configured to be: in contact with the ground surface when the first set of
ground
engaging members are in the raised stowed position; and raised above and out
of contact
with the ground surface when the first set of ground engaging members are in
the lowered
deployed position. The ground engaging members are a first set of ground
engaging
members, and further comprising: a second set of ground engaging members
mounted to the
structural frame and configured to permit the mobile well service unit to move
in a direction
parallel to the axis. The second set of ground engaging members comprise
wheels. The
structural frame comprises a trailer chassis configured to be towed by a
truck. The structural
frame comprises a ground-engaging skid. The ground engaging members are
configured to
move laterally outward, relative to a center of gravity of the mobile well
service unit,
between a laterally extended position and a laterally retracted position. Each
of the ground
engaging members comprises an actuator connected to move the ground engaging
member
between the laterally extended position and the laterally retracted position.
The actuator
comprises a hydraulic cylinder. The ground engaging members are configured to
be steered
about a range of two or more angular positions. The range of two or more
angular positions
include: a first position where the ground engaging members point in an axial
direction; and
a second position where the ground engaging members point in a lateral
direction relative to
the axis. The ground engaging members comprise continuous tracks and in which
the ground
engaging members are configured to move, relative to the structural frame,
between: a raised
stowed position, where the ground engaging members out of contact with the
ground and are
in the first position; and a lowered deployed position, where the ground
engaging members
contact the ground surface and are in the second position. In which, for each
ground
engaging member, the range of two or more angular positions include a
plurality of positions
where the ground engaging member points in different respective lateral
directions relative to
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the axis. The ground engaging members each comprise an angular locking system
to lock the
ground engaging member in a selected angular position of the range of two or
more angular
positions. The angular locking system comprises: a locking part; a first part
supporting the
locking part and connected to the respective ground engaging member; and a
second part
connected to the structural frame, the first part being mounted to rotate
relative to the second
part to define the range of two or more angular positions, the second part
defining a plurality
of slots that align to receive the locking part in different respective
angular positions relative
to the first part. In which: the first part comprises a collar; the second
part comprises a collar
or disc nested within the first part; and the locking part comprises a pin
biased to advance
into contact with the second part. In which the platform comprises floor
panels mounted to
move between an extended position and a retracted position toward or away from
an oil or
gas well adjacent the platform in use. Using the ground engaging members to
move the
mobile well service unit laterally across the ground surface from a first oil
or gas well to a
second oil or gas well. In which moving is carried out using continuous
tracks. In which:
moving is carried out using a first set of ground engaging members; and
positioning is
carried out using a second set of ground engaging members to advance the end
of the
structural frame toward the first oil or gas well. In which: during moving the
second set of
ground engaging members are out of contact with a ground surface; and during
positioning
the first set of ground engaging members are out of contact with the ground
surface. The
structural frame comprises a trailer chassis; the second set of ground
engaging members
comprise wheels; the end of the structural frame is a rear end; and
positioning comprises
backing the trailer chassis using a truck connected to a front end of the
structural frame until
the rear end is adjacent the first oil or gas well. After moving the mobile
well service unit to
the second oil or gas well, towing the trailer chassis away from the second
oil or gas well.
Servicing the first oil or gas well and the second oil or gas well using the
mobile well service
unit. Prior to, during, or after positioning, extending floor panels of the
platform into an
extended position to facilitate access to the first oil or gas well; prior to
moving, retracting
the floor panels into a retracted position; and prior to, during, or after
moving, extending the
floor panels of the platform into the extended position to facilitate access
to the second oil or
gas well.
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[0012] These and other aspects of the device and method are set out in
the claims,
which are incorporated here by reference.
BRIEF DESCRIPTION OF THE FIGURES
[0013] Embodiments will now be described with reference to the figures,
in which
like reference characters denote like elements, by way of example, and in
which:
[0014] Fig. 1 is a perspective view of a mobile well service unit with
ground
engaging members in a raised stowed position.
[0015] Fig. 2 is a rear elevation view of the mobile well service unit
of Fig. 1 with
ground engaging members in the raised stowed position.
[0016] Fig. 3 is a side elevation view of the mobile well service unit
of Fig. 1 with
ground engaging members in the raised stowed position.
[0017] Fig. 4 is a close up view of the area delineated by dashed lines
in Fig 3.
[0018] Fig. 5 is a perspective view of the mobile well service unit of
Fig. 1 with
ground engaging members in a lowered deployed position.
[0019] Fig. 6 is a rear elevation view of the mobile well service unit
of Fig. 5.
[0020] Fig. 7 is a side elevation view of the mobile well service unit
of Fig. 5.
[0021] Fig. 8 is a close up view of the area delineated by dashed lines
in Fig 7.
[0022] Fig. 9 is a perspective view illustrating a method of translating
the mobile
well service unit of Fig. 1 laterally across a ground surface from a first oil
or gas well to a
second oil or gas well with the ground engaging members in a lowered deployed
position,
and the platform in a raised position.
[0023] Fig. 10 is a side elevation view of the mobile well service unit
of Fig. 9.
[0024] Figs. 11-14 are a series of top plan views illustrating a method
of servicing
plural wells with the mobile well service unit of Fig. 1.
[0025] Fig. 15 is a rear elevation view of the mobile well service unit
of Fig. 9.
[0026] Fig. 16 is an exploded view of the area delineated by dashed
lines in Fig 15.
[0027] Fig. 17 is an exploded view of a ground engaging member of the
mobile well
service unit of Fig. I.
CA 2993846 2018-02-02
[0028] Fig. 18 is a partial section view taken along the 18-18 section
lines from Fig.
16.
[0029] Fig. 19 is a first partially exploded view of a continuous track
assembly of the
mobile well service unit of Fig. 1.
[0030] Fig. 20 is a second partially exploded view of the continuous
track assembly
of Fig. 19.
DETAILED DESCRIPTION
[0031] Immaterial modifications may be made to the embodiments described
here
without departing from what is covered by the claims.
[0032] Oil or gas wells may require servicing during the lifetime of the
wellbore, for
example to maintain and / or increase production such as by acidizing or
fracturing the
formation, perform testing on the formation or the wellbore integrity, replace
components
such as sucker rods or production tubing or casing, or to perform a variety of
other suitable
operations. Slickline, coiled tubing, snubbing and workover rigs or rod units
may be used in
well service activities. Well servicing includes the maintenance procedures
performed on an
oil or gas well after the well has been completed and production from the
reservoir has
begun. Well servicing may also include operations on the well during
exploration and
completion.
[0033] Well service rigs are generally mobile or portable rigs, for
example having a
transportable platform mounted on a chassis or undercarriage. Such rigs may be
powered by
a propulsion system for moving the rig from wellsite to wellsite. Unlike
drilling rigs, service
rigs may return to a particular well many times. The rig may be a mobile
truck, for example
with a derrick and a cab for one driver, or trailer-mounted, enabling it to be
towed behind a
prime mover, such as a tractor unit, also called a semi-truck. Traditionally,
trailer-mounted
service rigs are larger and heavier, with greater capacities relative to rigs
that integrate a
truck with a servicing platform. Service rigs may be capable of carrying a
significant amount
of weight given the diverse equipment mounted thereon and must also be able to
meet
regulations governed by road bans to permit servicing of wellbores throughout
the year and
under a variety of environmental condition. A rig crew may use the equipment
on the rig to
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perform a variety of services, including completions, work-overs,
abandonments, well
maintenance, high-pressure and critical sour-well work, and re-entry
preparation, as well as
other operations.
[0034] Well servicing may require performance of work at elevated
locations,
manipulation of heavy equipment, and / or positioning of workers at various
positions about
the work structures, such as the wellhead, while ensuring worker safety at
various heights.
Service rigs may have a work platform that may be elevated from the level of
its support
base, for example to provide ease of worker access to various parts of the
structure on
demand. In some cases, the rig may incorporate a derrick to mount the
platform. Once
secured on location, the derrick may be elevated to a standing position with
the use of
hydraulics. After that, the rest of the rig may be assembled and the service
process initiated.
[0035] Referring to Figs. 1-3, 5-7, 9-10, and 15, a mobile well service
unit 10 is
illustrated comprising a structural frame 12, a platform 14, and ground
engaging members
16. Referring to Figs. 3, 7, and 9, the structural frame 12 may have a front
end 12A and a
rear end 12B, and may define an axis I2C between the front end 12A and the
rear end 12B.
Referring to Figs. 1, 3, 5, 7, and 9-10, at least during servicing, the
platform 14 may be
mounted at, for example adjacent or near, the front end 12A or the rear end
12B of the
structural frame 12. The mobile well service unit 10 may be used to service an
oil or gas well
56. Various parts of the unit 10 may be configured to move relative to the
other parts of the
unit. Referring to Figs. 9, 10, and 15, the platform 14 may be configured to
move up and
down, for example in directions 14A, relative to the structural frame 12. The
ground
engaging members 16 may be mounted to the structural frame 12. The members 16
may be
configured to move one or more of side to side, up and down, and rotate about
an axis
relative to the frame 12.
[0036] Referring to Fig. 9, the frame 12 may have a structure suitable
for being
transported to and from a well site 17. For example the unit 10 may form a
trailer, which
may in use be towed to a desired location. The structural frame 12 may
comprise a trailer
chassis 58 configured to be towed by a tractor unit such as a truck 60. The
trailer may form a
gooseneck trailer, which may have a coupler 13 adapted to mate with and be
towed by a fifth
wheel hitch 15. Other suitable connection methods may be used. A ball and
hitch coupling
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may be used. In other cases the unit 10 may be integrally connected to a prime
mover, such
as in the case where the unit 10 has a portion that forms a truck, with an
engine, drivetrain,
and associated control, cab, and other components, and the unit has another
portion that
locates the platform 14. In some cases the structural frame 12 comprises a
ground-engaging
skid. A skid-mounted unit may be adapted to be transported on a separate
trailer or other
unit. Referring to Figs. 1-3 and 9, the structural frame 12 may comprise a
plurality of landing
gear or outriggers 84, for example for stabilizing the structural frame 12.
Outriggers 84 may
be moved laterally outward relative to center of gravity 91 of the unit 10.
Referring to Fig. 9,
the chassis 58 may have end and side railings 188, for example to enhance
worker safety.
[0037] Referring to Fig. 9, the ground engaging members 16 may be
configured to
permit the mobile well service unit 10 to move laterally, for example in a
direction 16A,
relative to the axis 12C, across a ground surface 18. The ground engaging
members 16 may
comprise parts, such as continuous tracks 20 or other parts, suitable for
permitting lateral
movement of the mobile well service unit 10, for example in the direction 16A
and 42. The
ground engaging members 16 may be used to translate the mobile well service
unit 10
laterally, for example in the direction 16A, across the ground surface 18 from
a first oil or
gas well 56' to a second oil or gas well 56". The ability to move the unit 10
laterally may
assist in the ability to position or reposition the unit 10 at various
locations at the well site. In
some cases, the unit 10 may be moved without the assistance or a tractor unit,
for example in
the cases of a skid or trailer. By contrast, a conventional servicing rig
built on a fixed axle
wheeled trailer can only be repositioned using a relatively complex series of
movements
initiated and driven by the tractor unit, and potentially obstructed by the
presence of adjacent
infrastructure or equipment at the well site.
[0038] Referring to Figs. 1-3, 5-7, 9-10, and 15, the mobile well
service unit 10 may
have plural sets of ground engaging members 16. Referring to Fig. 9, the
ground engaging
members 16 may include a first set of ground engaging members 26 and a second
set of
ground engaging members 28. The different sets of members 26 and 28 may be one
or more
of mounted, structured, and oriented to perform different functions. For
example the
members 26 and 28 are structured as different types of ground engaging
members, such as
tracks 20 in the case of members 26, and wheels 32 in the case of members 28.
In other cases
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the members 26 and 28 are of the same type, for example wheels. In some cases
the different
sets of members are adapted to move the unit 10 in different directions. For
example, the
members 28 may be adapted to move the mobile well service unit 10 in a
direction 30
parallel to the axis 12C between the front and rear ends 12A and 12B. One or
more of the
sets of members, such as tracks 20, may be structured to change orientation,
for example by
one or more of rotating, raising/lowering, or extending/retracting, while the
other set of
members may be adapted to remain fixed, or otherwise have relatively reduced
adjustability,
such as in the case of fixed axle trailer wheels 32. In some case plural sets
of members may
be adjustable in orientation. In some cases the sets of members cooperate with
one another to
move the unit 10, and in other cases the sets of members work independently of
one another
in different modes. Some or all of the ground engaging members 16 may be
active, for
example driven by a motor, while some may be passive, during operation.
[0039] Referring to Figs. 1-3, 5-10 and 15-16, each ground engaging
member 16 may
have a structure suitable for moving into and out of contact with the ground
surface 18.
Referring to Figs. 1-3, 5-7, 9-10, and 15, the ground engaging members 16 may
be
configured to move, relative to the structural frame 12, between a) a raised
stowed position,
where the ground engaging members 16 are out of contact with the ground
surface 18, for
example as illustrated in Figs. 1-3, and b) a lowered deployed position, where
the ground
engaging members 16 contact the ground surface 18, for example as illustrated
in Figs. 5-7,
9-10, and 15.
[0040] Referring to Figs. 1-3, 9-10, 15, and 17, each of the ground
engaging
members 16 may comprise an actuator 22 connected to move the ground engaging
member
16 between the raised stowed position and the lowered deployed position.
Referring to Fig.
17, the actuator 22 may comprise a hydraulic cylinder 24, for example having a
cylindrical
barrel or body 24A and a piston rod 24B mounted to extend out of or retract
into the body
24A in response to forces applied by pressurized hydraulic fluid. The
actuator, such as
cylinder 24, may be mounted to cause telescopic action of various parts
relative to one
another, such as a pair of nested columns 160 and 162. The actuator may be
mounted in a
suitable fashion to cause the parts to telescope, for example the cylinder 24
may be mounted
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within the columns 160 and 162 as shown. In other cases cylinder 24 may be
mounted to
external surfaces of the columns.
[0041] The cylinder 24 may be mounted between the members 16 and the
frame 12
via a suitable mechanism. The cylinder body 24A may be connected to outer
column 160, for
example via a pin 154 or other suitable part. The pin 154 may be concurrently
received by
holes 158 of the cylinder body 24A and holes 184 of the outer column 160. The
cylinder
body 24A may be positioned within a channel 160A defined by the outer column
160.
Bushings 156, or bearings, may be used, for example to mount the pin 154
within holes 184.
The piston rod 24B may be connected to inner column 162, for example via a pin
164 or
other suitable part. The pin 164 may be concurrently received within holes 166
of the piston
rod 24B and holes 174, for example of mounting parts 172. Parts 172 may be
mounted in a
suitable fashion to the inner column 162, for example within slots or channels
168 defined
by the inner column 162. Pin 164 may be mounted to part 172 via a retaining
ring 170,
bushing, bearing or other suitable part. Holes may refer to slots or channels
in some cases.
The actuator 22 may be mounted in other configurations, for example on the
outside of the
columns 160, 162. Actuators in this document other than hydraulic cylinders
may be used,
for example screw jacks, chain and sprockets, pulleys, and other devices. A
lock (not shown)
may be used to lock the cylinder in a desired position, for example one or
more of the raised
and lowered positions.
[0042] For all actuators a power source, for example a hydraulic supply
and return
circuit with a reservoir, pump, lines, and associated controls, may be
present. The hydraulic
power source may be the same power source used to operate the telescoping
platform mast.
A control system may be used to bypass one or both the platform
raising/lowering, platform
extension/retraction, and track drive circuits. Actuators may provide one or
more of
independent height and lateral extension control.
[0043] Referring to Figs. 1-10 and 15-16, the raising and lowering of
the members 26
may cause the members 28 to engage and disengage the ground surface 18 in use.
Referring
to Figs. 2 and 3, the ground engaging members 28 may be configured to be in
contact with
the ground surface 18 when the first set of ground engaging members 26 are in
the raised
stowed position. While stowed the members 26 may be positioned in a pocket
defined by the
CA 2993846 2018-02-02
frame 12. Referring to Figs. 6-8, 10 and 15-16, ground engaging members 28 may
be
configured to be raised above and out of contact with the ground surface 18
when the first set
of ground engaging members 26 are in the lowered deployed position. By
permitting the
members 26 to be used to raise the members 28 out of ground contact, the
members 26 are
free to operate without interference by members 28. Such may be advantageous
when
members 28 are fixed axle load-bearing transport wheels 32 as shown, and
members 26 are
used to move the unit 10 laterally relative to a direction of travel defined
by the wheels 32.
[0044] Referring to Figs. 2-3, 7 and 9, the ground engaging members 16
may be
configured to move laterally outward relative to a center of gravity 91 (Fig.
9) of the unit 10.
Referring to Figs. 1-2, 9, and 15-16, the ground engaging members 16 may be
configured to
move laterally, relative to the axis 12C (Fig. 9) and the structural frame 12,
across the ground
surface 18. The movement may be between a laterally extended position, for
example as
illustrated in Figs. 9 and 15-16, and a laterally retracted position, for
example as illustrated in
Figs. 1-2. Across the ground surface in this document includes moving in and
out of contact
with the ground surface unless context dictates otherwise. Laterally extending
the members
16 prior to moving the unit laterally may increase the stability of the unit
10, in a fashion
similar to or in addition to outriggers.
[0045] Referring to Figs. 8 and 17, each of the ground engaging members
16 may
comprise an actuator 36 connected to move the ground engaging member 16
between the
laterally extended position and the laterally retracted position. Embodiments
of actuators 36
may incorporate the same structures and principles of operation as embodiments
of actuators
22 and vice versa. Referring to Fig. 17, the actuator 36 may comprise a
hydraulic cylinder
38, for example having a cylindrical barrel or body 38A and a piston rod 38B
mounted to
extend out of and retract into the cylinder body 38A in response to forces
applied by
pressurized hydraulic fluid. The actuator 36 may be mounted to cause
telescopic action of
various parts relative to one another, such as a pair of nested columns, such
as columns 62A
and 62B. The members 16 may be mounted to the frame 12 via respective arms,
which
include column 62A in the example shown. Stops may be used to prevent over or
under
extension of columns relative to one another. The actuator may be mounted in a
suitable
fashion to cause the parts to telescope, for example the cylinder 38 may be
mounted to
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external surfaces of columns 62A and 62B as shown. In other cases cylinder 38
may be
mounted within the columns.
[0046] Referring to Figs. 17 and 18 the cylinder 38 may be mounted
between the
members 16 and the frame 12 via a suitable mechanism. The cylinder body 38A
may be
mounted to column 62A via a part 151 of body 3,8A that is connected to column
62A, for
example via a pin (not shown) or other rotatable or fixed connection. The
piston rod 38B
may be connected to inner column 62B, for example via a pin (not shown) or
other suitable
part. The pin may be concurrently received within holes 153 of the piston rod
38B and holes
155, for example of plates 152. Pins may be mounted via a retaining ring,
bushing, bearing
or other suitable part. Holes may refer to slots or channels in some cases.
[0047] Referring to Fig. 17, the ground engaging members 16 may be
locked in one
or both the laterally extended or retracted positions, via a lock 138. The
lock 138 may have a
suitable structure such as a locking pin 140, which may be received in use by
aligned holes
148 of column 62A and one of holes 144 or 146 of column 62B depending on the
position of
the columns relative to one another. In the example shown the lock 138 may
lock the
members 16 in one, two or more lateral positions, for example two positions
defined by
respective pin receiving holes 144 and 146 in the example shown. The pin 140
may be
received by pin boss 142, for example mounted to column 62A. The pin 140 may
be biased
into engagement or contact with the column 62B, and may be pulled out of
contact with
column 62B against the biasing force to unlock the column 62B.
[0048] Referring to Figs. 3-4 and 7-9, the ground engaging members 16
may be
configured to be steered about a range of angular positions, for example an
incremental or
infinite number of positions. In some cases the steerability of the members 16
permits the
unit 10 to be driven in different directions, such as front, back, sideways,
or at angles
between front /back and sideways, such as forty five degrees. In some cases
the steerability
of the members 16 permits the members 16 to be stowed and deployed in
different
orientations. Referring to Figs. 3-4 and 7-8A a range of two or more angular
positions may
include a first position where the ground engaging members 16 point in an
axial direction 40.
Steering may be accomplished using a manually adjusted mechanism, such as is
shown in
the drawings where a user performs all the steps required to rotate the
members 16, for
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example while the members 16 are above the ground, or a driven mechanism that
uses a
motor or other drive source.
[0049] Referring to Fig. 9, the range of angular positions may include a
second
position where the ground engaging members 16 point in a lateral direction 42,
for example
relative to the axis 12C, for example as illustrated in Fig. 9. For each
ground engaging
member 16, the range of two or more angular positions may include a plurality
of positions
where the ground engaging member 16 points in different respective lateral
directions
relative to the axis 12C. Each angular position refers to a different lateral
direction in which
the member 16 is pointed. Referring to Figs. 3-4, and 9, the ground engaging
members 16
may be configured to move, relative to the structural frame 12, between a) a
raised stowed
position, where the ground engaging members 16 are out of contact with the
ground surface
18 and are in the first position, for example as illustrated in Figs. 3-4, and
b) a lowered
deployed position, where the ground engaging members 16 contact the ground
surface 18
and are in the second position, for example as illustrated in Fig. 9. Stowing
the tracks 20 in
an axial or other position and deploying in a lateral position may permit the
tracks 20 to
provide the unit 10 with a relatively smaller lateral footprint when the
tracks 20 are stored at
the sides of the unit as shown, whilst still permitting the tracks 20 to be
deployed in a
suitable orientation to drive the unit 10 laterally. Steering the members 16
may include
rotating the members about an axis that has a vertical component, such as a
vertical axis.
[0050] Referring to Figs. 4, 8, and 16-17, the ground engaging members
16 may be
lockable in a desired angular position. For example the members 16 may each
comprise an
angular locking system 44 to lock the ground engaging member 16 in a selected
angular
position of a range of angular positions. Referring to Figs. 17-18, the
angular locking system
44 may comprise a locking part 46, a first part 50, and a second part 48. The
first part 50
may support the locking part 46 and be connected to the member 16. The second
part 48 may
be connected, for example directly or indirectly as shown, to the structural
frame 12. The
first part 50 may be mounted to rotate relative to the second part 48 to
define the range of
two or more angular positions. The second part 48 may define a plurality of
slots 51 that
align to receive the locking part 46 in different respective angular positions
relative to the
first part 50. The first part 50 may comprise a collar or other arcuate part,
or a part that is
13
CA 2993846 2018-02-02
configured to move about an arcuate path. The second part 48 may comprise a
collar or disc,
or other arcuate part, for example a disc as shown, or other part configured
to move about an
arcuate path. The second part 48 may be nested within the first part 48.
[0051] Referring to Figs. 17 and 18, the locking part 46 may operate via
a suitable
mechanism. The locking part 46 may comprise a pin 46A biased to advance into
contact with
the second part 48, for example via a spring 46B that encircles the pin 46A. A
pin 46C may
mount the spring 46B to the pin 46A, by mounting within and extending out of a
hole 46G of
the pin 46A. The spring 46B may apply a pushing force on the pin 46A towards
the second
part 48, for example radially inward in the example shown. The locking part 46
may
comprise a boss 46D that supports the pin 46A on the member 16. The boss 46D
may
receive the pin 46A via a hole 46E. The boss 46D may support the spring 46B
and the pin
46C within an interior channel 46F in the boss 46D. A channel 46H in the boss
46D may be
structured to receive the pin 46A, for example when the pin 46A is in a
retracted position out
of contact with the second part 48 and positioned radially outward relative to
the second part
48. pulling and rotation of the pin 46A, to maintain the parts in an unlocked
configuration
and permit rotation of the member 16 into a different angular position. The
disc or part 48
may be connected to rotate with column 162 via parts 172A. A retaining ring
176 may be
mounted to the first part 50, for example via a plurality of bolts 186 or
other suitable
fasteners, to retain the second part 48 within an internal cavity defined by
the ring 176 and
part 50. To operate the locking part 46 a user may pull on and turn the pin
46A by grasping a
handle 461 connected to the pin 46A. Upon releasing the handle 461 the pin 46A
slides back
into contact with the second part 48 via the action of spring 46B.
[0052] Referring to Figs. 4, 8, and 16-17, the tracks 20 may have a
suitable structure.
Each ground engaging member 16 may be mounted to the frame 12 via an arm, such
as
column 62A. The tracks 20 may be connected to frame 12 via a bracket or jaw
64, for
example via a pin 67. Referring to Figs. 4, 17, and 19-20, each track 20 may
include a track
assembly 66, for example having one or more of a track frame 68, a drive wheel
or sprocket
wheel 70, a driven or non-powered wheel such as an idler wheel 72, and a road
wheel or
roller 74. The sprocket wheel 70, the idler wheel 72, and the roller 74 may be
rotatably
mounted to the track frame 68.
14
CA 2993846 2018-02-02
[0053] Referring to Figs. 19-20, the track frame 68 may comprise a first
part 68A
and a second part 68B, for example that cooperate to mount and retain one or
more of the
sprocket wheel 70, the idler wheel 72, and the roller or rollers 74. The
rollers 74 may be
mounted to the first part 68A via screws 190 or other suitable fasteners, for
example
positioned within respective holes 198 in part 68A. The rollers 74 may be
mounted to the
second part 68B via screws 192 or other suitable fasteners, for example
positioned within
respective holes 200. The track assembly 66 may comprise any suitable number
of wheels
and rollers or one or the other. The track assembly 66 may comprise a part,
such as a
cylinder 202, for example structured to receive and mount the pin 67 and
positioned within a
hole 194 of the first part 68A and a hole 196 of the second part 68B.
[0054] Referring to Figs. 19-20, the track assembly 66 may have a
suitable system
for maintaining sufficient tension in the track 20. For example, a shock
absorbing spring
strut 171 may be mounted on the frame 68 to apply a continuous force to
separate the wheels
70 and 72 to apply tension on the track 20. The wheels 70 and 72 may be
mounted on sub-
frame parts 73A and 73B, respectively. The strut 171 or other biasing member
may be
mounted between parts 73A and 73B.
[0055] Referring to Figs. 4, 17, and 19-20, the continuous track 20 may
encircle the
sprocket wheel 70, the idler wheel 72, and the roller 74 to form an endless
loop. The
continuous track 20 may comprise a continuous band of treads, for example
rubber treads, or
track plates, for example modular steel plates. Referring to Figs. 4, 8, and
19-20, the sprocket
wheel 70 may have a plurality of cogs or teeth 82, for example that engage the
continuous
track 20. Referring to Figs. 16 and 19-20, the sprocket wheel 70 may be driven
by a motor
71 or other suitable part or mechanism. Referring to Figs. 4, 8, 16-17, and 19-
20, the
sprocket wheel 70 and the idler wheel 72 may be positioned at opposite ends
66A and 66B of
the track assembly 66. The roller 74 may be positioned between the sprocket
wheel 70 and
the idler wheel 72. Referring to Fig. 17, one or more of a pin boss 178, a
retaining ring 180,
and a part 182 may be mounted to the jaw 64. Tracks 20 may be useful
particularly on soft
ground surfaces for obtaining the required traction to move the unit 10.
Wheels may be used
instead of tracks, although in some cases tracks have a relatively smaller
height than suitable
comparable wheels.
CA 2993846 2018-02-02
[0056] Referring to Fig. 9, the mobile well service unit 10 may have a
platform 100,
and associated structure suitable for providing workers with elevated access
to the oil or gas
well 56. The platform 14 may comprise a plurality of platforms, such as an
upper platform
100 and a lower platform 98. The platform or platforms 14 may be mounted on a
mast 88
with a first frame part 90 and a second frame part 92. The first frame part
90, for example
comprising columns 94, may be mounted on the rear end 12B of the structural
frame 12. The
first frame part 92 may mount the lower platform 98, for example with a pair
of columns 94
on each side 12E of the structural frame 12. The second frame part 92, for
example
comprising columns 96, may support the upper platform 100, for example with a
pair of
columns 96 on each side 12E of the structural frame 12. The columns 96 may be
mounted to
slide up and down along the first frame part 90, for example by insertion of
base ends 96A of
columns 96 within top ends 94A of respective channels defined by columns 94.
The columns
96 may nest within the columns 94. The first frame part 90 and the second
frame part 92 may
comprise four columns 94 and four columns 96, respectively. Cross beams 102
may connect
each column 94 in a respective pair of columns 94. Actuators (not shown), for
example
hydraulic cylinders with cooperating cylinder and piston parts, may be used
for sliding the
top platform 100 up and down. The lower platform 98 may also slide up and
down.
[0057] Referring to Fig. 15, during use an under surface 100A of the
upper platform
100 may be vertically spaced a distance 104 from an upper surface 98A of the
lower
platform 98. Distance 104 may be sufficient to define a standing work area
between the
lower platform 98 and the upper platform 100. A standing work area may be of a
sufficient
height to permit an adult male of average height to walk freely around within
the work area.
[0058] Referring to Figs. 1, 9 and 11-14, the platform or platforms 14
may have a
structure suitable for moving between retracted and deployed positions to
facilitate a
compact stowed travel configuration and flexible worker access to the oil or
gas well 56,
respectively. The platform 14 may comprise floor panels, such as panels 106
and 108,
mounted to move between an extended position, for example as illustrated in
Figs. 11 and
14, and a retracted position, for example as illustrated in Figs. 9 and 12-13,
toward or away
from the oil or gas well 56 adjacent the platform 14 in use. The floor panels
106 and 108
may be configured to provide worker access to various parts of a Christmas
tree 57, for
16
CA 2993846 2018-02-02
example valves, gauges, or other suitable parts, a well head, or other
suitable structures of an
oil or gas well.
[0059] Referring to Figs. 1, 3, 5-6, and 9-10, the lower platform 98 and
the upper
platform 100 may each comprise a set of floor panels, for example a set of
lower floor panels
106 and a set of upper floor panels 108, respectively. Each floor panel 106
and 108 may be
mounted to move independently relative to the other floor panels of the
respective set of
floor panels 106 and 108, for example between a retracted position, for
example as
illustrated in Figs. 9-10, and an extended position, for example as
illustrated in Figs. 1, 3,
and 5-6. Referring to Fig. 9, each floor panel 106 and 108 may be mounted to
slide in a
forward direction 110A and a rearward direction 110B parallel to the axis 12C
of the
structural frame 12. In the extended position, the floor panels 106 and 108
may form weight-
bearing cantilevers. Floor panel extension and retraction may be controlled
via a suitable
actuator (not shown). Floor panels may move in lateral directions.
[0060] Referring to Figs. 1 and 2, each set of floor panels 106 and 108
may have
suitable configurations made up of a plurality of panels each. The set of
floor panels 106
may comprise a first side panel 106A, a central floor panel 106B, and a second
side floor
panel 106C. The set of floor panels 108 may comprise a first side panel 108A,
a central floor
panel 108B, and a second side panel 108C. The central floor panels 106B and
108B may
have shorter lengths than the first side floor panels 106A and 108A and the
second side floor
panels 106C and 108C. Thus, in the extended position, the floor panels 106 and
108 may
define a well gap 112. In some cases, one or more panels 106 and 108 are moved
to the
retracted position when accessing the oil or gas well 56 via the mobile well
service unit 10,
for example to adjust the shape of the well gap 112 to accommodate
obstructions or
protrusions located at the oil or gas well 56.
[0061] Referring to Fig. 2, the floor panels 106 and 108 may be mounted
to the
respective platforms 98 and 100 via a suitable mechanism. The floor panels 106
and 108
may be mounted to slide within axial channels 120 defined by rails 114. The
rails 114 may
be I-beams 116, C-beams 118 or other suitable parts.
[0062] Referring to Figs. 1 and 9, the platform 14, such as upper
platform 100, may
have a structure suitable for enhancing worker safety. Referring to Fig. 1,
the upper platform
17
CA 2993846 2018-02-02
100 may comprise safety railings 122. The railings 122 may comprise side
railings 124, for
example mounted to the first and second side floor panels 108A and 108C, and
front end
railings 126, for example mounted to a front end 100B of the upper platform
100. Railings
122 may partially or fully enclose a working portion 128. A lateral gap 130
may be defined
between front end railings 126 to provide access to upper platform 100 via a
staircase 132.
Prior to retraction of the first and second side floor panels 108A and 108C,
side railings 124
may be removed.
[0063] Referring to Figs. 1, 3, and 9-10, the mobile well service unit
10 may have a
structure suitable for providing worker access to the upper platform 100.
Referring to Figs. 3
and 10, the mobile well service unit 10 may comprise a staircase 132, for
example that
extends from a floor 12D of the structural frame 12 to the upper platform 100.
The staircase
132 may comprise one or more of stairs 132A, an upper end 132B, for example
pivotally
anchored to the upper platform 100, a lower end 132C, for example mounted to
slide along
chassis 58, for example by mounting rollers 132D. Staircase 132 may comprise
opposed side
rails 132E, and opposed side rails 132F, the opposed side rails 132E and 132F
mounted to
pivot as the staircase 132 rotates with height changes in the upper platform
100. The opposed
side rails 132E and 132F may be formed by C-beams, 1-beams, or other suitable
structural
members. Each opposed side rail 132F may have a respective length sufficient
to maintain a
gap 132N between the opposed side rail 132F and the floor 12D of the
structural frame 12 as
the staircase 132 rotates with height changes in the upper platform 100. The
staircase 132
may comprise safety railings 132M.
[0064] Referring to Figs. 3 and 10, the stairs 132A of the staircase 132
may be self-
levelling. As the upper platform 100 is elevated or lowered, the stairs 132A
may
automatically pivot relative to the opposed side stringers or rails 132E and
132F, for example
to remain horizontal and permit use of the staircase 132 by workers when the
upper platform
100 is at different elevations. Each stair 132A may comprise a respective pair
of opposed
flanges 1321, each flange 1321 having two pivot points 132J and 132K. The
opposed side
rails 132E may be pivotally connected to the upper platform 100 via plates
132L. As the
staircase pivots by the up and down action of the platform 100, the rails 132E
and 132F
move relative to one another and the rollers 132D slide along the chassis 58,
pivoting the
18
CA 2993846 2018-02-02
stairs 132A. Other mechanisms for levelling the stairs I32A may be used, for
example
mechanical, electronic, controller and sensor driven, and other suitable
mechanisms. The
stairs may be telescopic to increase and decrease in length during rising and
lowering of
platform 100.
[0065] Referring to Fig. 9, the mobile well service unit 10 may be
transported, for
example towed, to the first oil or gas well 56' via the truck or other
suitable vehicle,
travelling down a road or highway to the well site 17. After the mobile well
service unit 10 is
positioned at a suitable location, for example at a well site 17 adjacent an
oil or gas well 56',
the mobile well service unit 10 may be unhitched from the truck 60. In some
cases, the
mobile well service unit 10 is unhitched prior to positioning the mobile well
service unit 10
adjacent the first oil or gas well 56'. Ground engaging members 26 may be used
to position
the unit 10 in some cases. The outriggers 84 may be extended to the ground
surface 18, for
example to stabilize the mobile well service unit 10 in a parked servicing
position.
[0066] Positioning may be carried out using the second set of ground
engaging
members 28 (wheels 32) to advance an end of the structural frame 12, for
example the rear
end 12B of the structural frame 12, towards the first oil or gas well 56'.
During positioning,
the first set of ground engaging members 26 (tracks 20) may be out of contact
with the
ground surface 18. Positioning may comprise backing the trailer chassis 58
using a truck 60
connected to the front end 12A of the structural frame 12 until the rear end
12B is adjacent
the first oil or gas well 56'.
[0067] Referring to Fig. 9, the upper platform 100 may be elevated to a
height
suitable for providing worker access to the first oil or gas well 56'. A
worker may access the
upper platform 100 via the staircase 132. Referring to Fig. 11, the floor
panels 106 and 108
may be extended beyond the rear end 12B to facilitate worker access to the
first oil or gas
well 56'. In some cases, one or more floor panels 106 and 108 remain in the
retracted or
partially retracted position to avoid contact with obstructions or protrusions
or equipment
located at the first oil or gas well 56'. The floor panels 106 and 108 may be
extended before
or after elevating the upper platform 100 and before or after positioning the
unit 10. The
outriggers 84 may be extended to the ground surface 18 before or after
extending the floor
19
CA 2993846 2018-02-02
panels 106 and 108. The side railings 124 (Fig. 1) may be mounted to the upper
floor panels
108A and 108C that are in the extended position, for example to enhance worker
safety.
[0068] Referring to Fig. 11, once the unit 10 is positioned, the first
oil or gas well 56'
may be serviced, for example using equipment stored on the mobile well service
unit 10.
After servicing is complete, the railings 124 may be removed. The floor panels
106 and 108
may be retracted. The upper platform 100 may be lowered to a suitable
elevation.
[0069] Referring to Figs. 9 and 12-13, the mobile well service unit 10
may be moved
or translated laterally across the ground surface 18 from the first oil or gas
well 56' to the
second oil or gas well 56". Translating may be carried out using the first set
of ground
engaging members 26. During translating, the second set of ground engaging
members 28
may be out of contact with the ground surface 18. All members 16 may be
pointed in the
same direction as one another to facilitate translation. In other cases the
unit 10 is moved by
having some members 16, which may be driven or not, steer the unit 10 into
position while
other members 10, which may be driven or not, follow without steer, much like
the front and
rear wheels on a car. Permitting the unit 10 to be translated to the second
well 56" may
negate a need to involve the truck 60 to reposition the unit 10, which may be
advantageous if
the truck 60 is otherwise blocked from doing so by other equipment or
infrastructure, and
may be advantageous in general as operation is simplified and several steps
are omitted,
namely the steps of connecting the unit 10 to the truck 60, maneuvering the
unit 10 by
advancing, turning, and backing up the truck 60, and disconnecting the unit 10
from the
truck 60.
[0070] Referring to Fig. 14, prior to, during, or after movement or
translation of the
mobile well service unit 10, the floor panels 106 and 108 may be extended to
facilitate
worker access to the second oil or gas well 56'. Prior to, during, or after
extending the floor
panels 106 and 108, the upper platform 100 may be elevated to a desired
working height.
The side railings 124 (Fig. 1) may be mounted to the side floor panels 108A
and 108C, for
example to enhance worker safety. The second set of ground engaging members 28
(wheels
32) may be used to increase or decrease the distance between the rear end 12B
of the
structural frame 12 and the second oil or gas well 56", for example prior to
or after moving
CA 2993846 2018-02-02
or translating the mobile well service unit 10. The members 26 (tracks 20) may
be steered
during translation to properly position the unit 10 adjacent the second well
56".
[0071] Referring to Fig. 14, the second oil or gas well 56" may be
serviced, for
example using equipment stored on the mobile well service unit 10. After
servicing is
complete, the railings 124 may be removed. Referring to Fig. 13, the floor
panels 106 and
108 may be retracted. Referring to Fig. 1, the outriggers 84 may be retracted
out of contact
with the ground surface 18. The floor panels 106 and 108 may be retracted. The
mast, if any,
may be pivoted into a stowed position, and the unit 10 secured for road
transport.
[0072] Prior to leaving the well site 17, the mobile well service unit
10 may be used
to service additional oil or gas wells 56 located adjacent to the first and
second oil or gas
wells 56' and 56". Once servicing is complete, the structural frame 12 or the
trailer chassis
58 may be hitched to the truck 60 or other suitable vehicle. The truck 60 may
be used to tow
the mobile well service unit 10 to a storage facility, other well sites, or
other suitable
locations.
[0073] Words such as horizontal, vertical, up, down, upper, base, top,
lower, rear,
front, and other words are intended to be relative and not limited to fixed
meanings defined
with respect to the surface of the earth, unless context dictates otherwise.
The ends 12A and
12B may be reversed in some cases, such that the platform is at the front end,
or the ends
may simply be first and second ends on the frame, without reference to a front
or rear end.
The front end and rear end are defined by reference to a road direction of
travel, which may
be defined by the wheels 32 and / or the truck 60 but would be understood by a
skilled
worker in the field. The ability to move the unit 10 laterally relative to a
direction of road
travel increases the maneuverability and ease of use of the unit 10.
[0074] Connections and mounting of parts may be direct or indirect, for
example
through intermediate parts. A lateral movement has a horizontal component, for
example is
in the horizontal plane or a plane parallel to a plane defined by the ground
engaging
members 16 and / or ground surface in use. A lateral direction may form a non-
zero angle
with the axis 12C. The axis 12C may be parallel to and coaxial with a
direction of road
travel. Rollers, skids, skis, or other devices may be used instead of wheels
or tracks.
21
CA 2993846 2018-02-02
[0075] In the claims, the word "comprising" is used in its inclusive
sense and does
not exclude other elements being present. The indefinite articles "a" and "an"
before a claim
feature do not exclude more than one of the feature being present. Each one of
the individual
features described here may be used in one or more embodiments and is not, by
virtue only
of being described here, to be construed as essential to all embodiments as
defined by the
claims.
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