U.S. patent number 3,913,669 [Application Number 05/318,977] was granted by the patent office on 1975-10-21 for method of installation and control of underwater equipment.
This patent grant is currently assigned to Subsea Equipment Associates Ltd.. Invention is credited to Andre Brun, Philippe DE Panafieu, Albert Jaffe.
United States Patent |
3,913,669 |
Brun , et al. |
October 21, 1975 |
**Please see images for:
( Certificate of Correction ) ** |
Method of installation and control of underwater equipment
Abstract
A method for installing underwater equipment on a previously
installed underwater guide structure. The underwater equipment is
divided into at least a first unit and a second unit, and the first
unit is first lowered from a surface support onto the guide
structure by means of a manipulator, the second unit is then
lowered into place on top of the first unit, and then the two units
are connected together. The underwater steps can be accomplished
either by means of a remote-controlled manipulator or by a crew
working in a work bell or a submersible.
Inventors: |
Brun; Andre (Paris,
FR), Jaffe; Albert (London, EN), DE
Panafieu; Philippe (London, EN) |
Assignee: |
Subsea Equipment Associates
Ltd. (Hamilton, BM)
|
Family
ID: |
9088121 |
Appl.
No.: |
05/318,977 |
Filed: |
December 27, 1972 |
Foreign Application Priority Data
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|
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Dec 27, 1971 [FR] |
|
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71.46720 |
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Current U.S.
Class: |
166/349;
166/360 |
Current CPC
Class: |
E21B
33/038 (20130101); E21B 33/035 (20130101); E21B
41/04 (20130101) |
Current International
Class: |
E21B
33/035 (20060101); E21B 33/03 (20060101); E21B
33/038 (20060101); E21B 41/04 (20060101); E21B
41/00 (20060101); E21B 033/035 () |
Field of
Search: |
;166/.5,.6 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Leppink; James A.
Attorney, Agent or Firm: Sughrue, Rothwell, Mion, Zinn &
Macpeak
Claims
What we clain is:
1. A method of installing underwater petroleum production equipment
capable of operating at great depth, said method comprising the
steps of:
1. lowering a guide structure from a surface support by means of a
manipulator attached to a pipe column;
2. attaching said guide structure to a wellhead of an underwater
oil well by means of said manipulator;
3. lowering a first unit from said surface support onto said guide
structure by means of the or a further manipulator, said first
unit
a. being provided with a guide structure ensuring guiding of a
second unit to be recited,
b. being adapted to ensure continuity of the production passage in
said wellhead to said second unit, and
c. being adapted to control the closing and opening of said
production passage;
4. attaching said first unit to said guide structure;
5. lowering a second unit from said surface support onto said first
unit by means of a tool-carrier frame or a work crew, said second
unit being adapted to ensure the operation of a production
wellhead, the approach of said second unit to said first unit being
effected by
a. attaching the or a further manipulator to said tool-carrier
frame by a mechanical connection enabling displacement of said
tool-carrier frame relative to said manipulator,
b. maneuvering said manipulator above the guide structure provided
on said first unit,
c. lowering said manipulator and said tool-carrier frame onto the
guide structure provided on said first unit,
e. ensuring alignment and joining up of said first and second units
by the simple approach of said second unit to said first unit and
by displacement of said manipulator relative to said tool-carrier
frame; and
6. attaching said second unit to said first unit.
2. A method according to claim 1, wherein the passage in the first
unit adapted to ensure continuity between the wellhead and the
second unit is provided with a valve operable by an actuator
outside the first unit.
3. A method according to claim 1, wherein valves in the second unit
necessary to the operation of the said petroleum production
equipment are actuated by corresponding actuators carried by said
tool-carrier frame connected to the surface support by said pipe
column, and wherein, after connection of the second unit to the
first, checking of satisfactory operation of the said equipment
from the surface is carried out before controlling the operation of
this equipment from the surface, and then the tool-carrier frame
and the pipe column are withdrawn.
4. A method of installing on a guide structure and thereafter
controlling underwater equipment capable of operating at great
depth and divided into at least a first unit and a second unit,
said method comprising the steps of
1. lowering said first unit from a surface support onto the guide
structure by means of a manipulator;
2. lowering said second unit from said surface support onto said
first unit in an orientation such that corresponding portions of
the two units engage each other, the approach of said second unit
to said first unit being affected by
a. attaching the or a further manipulator to a toolcarrier frame
controlled from said surface support, the attachment being by means
of a mechanical connection enabling displacement of said tool
carrier-frame relative to said manipulator,
b. bringing said manipulator carrying said second unit above a
guide structure mounted on said first unit,
c. lowering said manipulator and said frame onto the guide
structure mounted on said first unit, and
d. ensuring exact alignment and joining up of the connection means
between said first and second units by displacement of said
manipulator relative to said tool-carrier frame;
3. connecting said second unit to said first unit;
4. actuating valves in said second unit necessary to the operation
of said underwater equipment by means of corresponding actuators
carried by said tool carrier frame;
5. checking the operation of said underwater equipment from said
surface support after connections of said second unit to said first
unit; and
6. withdrawing said manipulator and said tool-carrier frame.
5. A method according to claim 4 wherein connection of the second
unit to the first is effected by means of a tool carrier frame
attached to said manipulator and remote-controlled from the
surface.
6. A method according to claim 4, wherein connection of the second
unit to the first is effected by means of said tool-carrier
frame.
7. A method according to claim 4, wherein the approach of the
second unit to the first is affected by attaching the said
manipulator to a tool carrier frame by a mechanical connection
enabling displacement of the frame relative to the manipulator,
bringing the said manipulator carrying the second unit above a
guide structure mounted on the first unit, lowering the manipulator
and frame onto the said structure, and ensuring exact alignment and
joining up of the connection means of the first and second units at
the same time while displacing the manipulator relative to the
frame.
8. A method according to claim 7, wherein connection of the second
unit to the first is effected by means of said tool-carrier
frame.
9. A method according to claim 4, wherein there are provided valves
enabling opening or closing of passages in the second unit, each
having an external actuator carried by a tool carrier frame which
is provided with as many actuators as valves, with the opening or
closing of the valves being effected from the surface by remote
control of the said actuators.
10. A method according to claim 9, wherein the tool carrier frame
is carried by the manipulator.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method for the installation and control
of any underwater equipment, and more particularly to a method for
the installation and control of an underwater oil well access
equipment for the working of wells located at great depths,
especially depths greater than those within access of a diver.
2. Description of the Prior Art
Various systems of installation of underwater well access
equipments have been proposed, but none of them can at present be
employed in an economical and safe manner once the depth at the
well access exceeds 150 meters.
Furthermore, even if the conventional systems can be adapted for
the installation of wellhead access equipments, an extended
suspension of operation of the well access will be necessary to
repair any failure of any production control member at the wellhead
access in question.
SUMMARY OF THE INVENTION
This invention provides a method for the installation and control
of an underwater oil-well head located at great depth and having
its base surrounded by any structure which has served for drilling
the well, characterized in that a supporting structure round the
casing head is lowered in a first phase from a surface, support and
by means of a remote-controlled manipulator. In a second phase and
by means of a manipulator remote-controlled from the surface a
first detachable integrated unit is lowered, which has the function
of serving as a seating for a second integrated unit as well as
means of intermediate connection between the latter and the casing
head in order both to ensure the continuity of the production
passages and the opening or closing of these passages upstream of
the second unit and also to ensure the continuity, opening, and
closing of a gathering passage proceeding from this second unit.
The gathering passage from the first unit is connected to an
underwater gathering system of pipes, each passage being controlled
by means of a valve operated by any suitable external manipulator.
In a third phase and by means of a manipulator remote-controlled
from the surface, the second integrated unit is lowered, the latter
having the function on the one hand of a production tree ensuring
control of the flow in the production and gathering passages,
discharge being effected normally through the underwater gathering
system of pipes, and on the other hand the function of a means of
intermediate connection between the well and any surface support
with a view to transmitting any information on pressure,
temperature, and flow and receiving from the surface any valve
opening, closing, or adjusting commands. Such information can be
transmitted either by means of the manipulator or withdrawal of the
latter, by remote control.
The joining of the second unit to the first is facilitated by
equipping each of the members, the first unit and manipulator, with
a guide and protection structure so that in the course of the
lowering of the second unit the latter can possibly take on a
certain tilt and a certain offset relative to the axis of
connection of the first and second units without risk of damage to
the portions of these units employed for the connection, as is
often the case when the devices to be connected at the seabed are
only furnished with conventional impact dampers.
The presentation of the second unit relative to the first is
perfected by guiding a frame connected to the manipulator by means
of the guide structure surrounding the first unit and by displacing
the manipulator connected to the surface support, laterally and
vertically relative to the frame.
In advance of the first unit a structure is lowered to surround the
casing head in a watertight manner whilst being supported
vertically on a surface pipestring and laterally on a clamping
device between the said structure and the outer conductor string so
as to serve as a supporting base. The first unit is lowered by
means of a diving-bell that has been allowed to rest on this base.
It is then sufficient next to empty the bell by any known means and
to admit to it air at atmospheric pressure and then a work-crew in
order to proceed with the placing of the first unit under the
control of this crew.
Replacement of all members of the installation situated on the
seabed liable to become faulty is proceeded with by disconnecting
the second unit from the first by means of a remote-controlled
tool-carrier and by proceeding with replacement of these members at
the surface.
The advantage of this method is in being able to install the
equipments necessary to the exploitation of an underwater oilfield,
such as a production wellhead, at great depth automatically in
complete safety, the prior lowering of the first integrated unit
enabling through the possibility of operating valves controlling
the production passages, the avoidance of any premature setting of
the well in action during the placing of the second unit and of
checking straight from the surface the satisfactory operation of
all the control devices of the second unit after its connection
with the first.
Another advantage of this method is that, as opposed to previous
methods in which in order to treat failures of a complex underwater
equipment such as a wellhead or a separator one was compelled to
intervene frequently over a multiplicity of devices each fulfilling
a simple function and arranged so as to be accessible to
intervention manually or by a manipulator, which caused numerous
interruptions in production and multiplied the risks of damage or
the impossibility of intervention because of bad weather, it is
sufficient to proceed to the simple withdrawal of the unit
containing the various control members, to replace it immediately
with an identical unit in accordance with the method shown and to
repair the defective unit at the surface.
Another advantage of this method is in being able to proceed at the
smallest cost with preventive maintenance of the most elaborate and
often the least reliable underwater equipment by standard exchange
at fixed intervals of the unit containing this equipment.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 shows a perspective view of the lower guide structure of an
underwater wellhead access equipment;
FIG. 2 shows a perspective view of a supporting structure lowered
from a surface support;
FIG. 3 shows the assembly of the structures shown in FIGS. 1 and
2;
FIG. 4 shows a partial diagrammatic view of a device ensuring
locking of the tool carrying the supporting structure of FIG. 2
with the said structure;
FIG. 5 shows a view partially in section of a first alternative of
the supporting structure of FIG. 2 after connection with the first
detachable unit;
FIG. 6 shows a view partially in section of a second alternative of
the supporting structure of FIG. 2 after connection with the first
detachable unit;
FIG. 7 shows a diagrammatic elevation of the remote-controlled
load-carrying tool surrounding a wellhead equipment; and
FIG. 8 shows a diagrammatic view of a device for separation of the
detachable units.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1, 2, 3 and 4, the underwater wellhead access
equipment to be installed and controlled has been described in
applicants' copending patent application Ser. No. 318,972 filed on
Dec. 27, 1972, and titled "A Well-Head Assembly". A conventional
guide structure such as that shown at 1 in FIG. 1 has previously
been placed on the seabed by any known means. This structure
surrounds the outer conductor string 2 and comprises essentially a
rigid frame 3 serving as a support to vertical guide bars 4, and a
base 5. A unit 8 having pipes 14 for gathering oil from the well
head is lowered by means of a pipe column 6 or riser, including all
the means of remote control and remote transmission, to which is
connected a remote controlled manipulator 7, carrying all the means
of location and propulsion. The lowering of this first unit is
effected without a guideline connecting the surface to the well, by
neutralizing the effects of the swell by any known anti-pounding
system and by providing at least one means enabling suppression of
torque which would be exerted on the column during the movement of
the ship 9 or any other surface support.
The manipulator 7, which can be of any type and comprises
particularly means of self-guidance and self-propulsion, is
attached to the end of the column 6. In the example in FIG. 2 it
supports a supporting connector, partly seen at 10 in FIG. 3, the
unit 8 being connected to the support plate 11 in FIG. 3, the
bearing plate 64 in FIG. 5, or the support plate 75 in FIG. 6,
resting on a flange on the connector 10. The bearing plate 64 is
provided with a center hole of sufficient diameter to let the upper
portion of the connector 10 pass through it and to rest by its
periphery on a flange 12 seen in FIG. 5 and located on the lower
portion of the connector 10. The support plates 11 or 75 may be
similarly supported, and, as seen in FIG. 5, the support plate 11
may also be provided with appropriate apertures 22 for the passage
of the pipes 14, which are connected to gathering pipes 68, also
seen in FIG. 5 can include a structure 76 for protection of the
casing head 17 and guidance of a tool-carrier frame 30, FIG. 7,
which will be described later. The supporting connector 10 can be
connected to the plate 11, 64, or 75 in a watertight manner. It
surrounds one portion of the casing head 17 while being supported
on the intermediate surface casing 18, FIG. 1. When the unit 8 is
sufficiently near the guide bars 4 and the skirt 13 is right over
the top of all the bars, the unit 8 is orientated by means of the
remote controlled manipulator 7 so that the cutaway corners 11a of
the plate 11 are nearly above the bars 4. Guide surfaces such as
15, for example, FIG. 2, located below the plate 11, at the instant
of the lowering of the remote-controlled manipulator 7 guide the
bars 4 through the holes 16, FIG. 3, provided in the plate 11.
In the course of this lowering, the upper portion of the connector
10 slides round the casing head 17 and is stopped by the
intermediate casing 18, FIG. 1, on which it bears. A locking
mechanism locks the connector 10 onto the intermediate casing 18
whilst a clamping device unites the lower inner wall of the
connector 10 with the outer wall of the outer conductor string 2.
The locking, and, clamping mechanisms can be any kind and as they
do not form part of the invention, they have not been shown.
As soon as the locking has been effected the remote-controlled
manipulator 7 and/or another manipulator such as the tool-carrier
77 (shown in FIG. 4) are raised again and lowering proceeds of a
first detachable integrated unit as seen in FIGS. 5, 6 and 7 and
bounded in FIG. 5 between the dotted lines 62 and 63. Tool-carrier
77 or manipulator 7 is also used to install the supporting
connector 10, in contrast to tool-carrier frame 30, which is used
to lower the integrated unit 26 and to manipulate its valves, as
will be described further hereinafter. As shown in FIG. 4, means
are provided on tool-carrier 77 for locking it to supporting
connector 10. These means comprise spring 20, piston 19, cylinder
78, slot 10A in the supporting connector 10, and hydraulic tube 21
containing the control oil for the locking operation. The control
oil is used to push the piston 19 leftwards against the bias of the
spring 20 when it is desired to unlock the tool-carrier 77 from the
supporting connector 10.
As the invention refers to the method of installation and control
of any underwater equipment, of which the example selected in an
underwater wellhead, it will be understood that the structure
illustrated in FIG. 2 can take manifold forms, such as that shown
in FIG. 5. In the structure shown in FIG. 5, connector 10 supports
from the flange 12 a bearing plate 64 provided at its periphery
with annular surfaces 65 and 66 constituting with the connector 10
a completely watertight unit. Passages such as 67 enable the
connection of the gathering pipe 68 of the unit 61 to an underwater
gathering system of pipes by means of connectors of any known
type.
In accordance with a first variant a bell, or submersible unit,
carrying the unit 61, is lowered from the ship 9 by means of the
manipulator 7. As the bell can be of any known type and does not in
itself form part of the invention it has not been shown. The edges
of the bell, which is guided externally by the vertical guide bars
4, come to rest on the annular surface 65.
A work-crew lowered by any means provided with a lock chamber for
connection to the bell then proceeds, after replacement of the
water trapped by the bell with air at near to atmospheric pressure,
to unlock the unit 61 from its support and lower it in order to fit
it onto the casing head 17 and to connect the gathering pipe 68 to
the passage 67. A connector 70 locks the unit 61 onto the casing
head 17. Means 71, shown schematically in FIG. 5, permit
orientation of unit 61 with respect to casing head 17. The valve
72, which controls the production, A valve 73 which controls the
pipe connected to the annular space, and valve 74 which controlls
the gathering pipework can be operated manually or by any sort of
manipulator device.
Instead of a work-crew, a tool-carrier frame can also be employed,
such as that shown diagrammatically at 30 in FIG. 7, which serves
to protect and to fix in the working position the two integrated
units 61 and 26. For clarity in the drawing, the frame and the two
units 26 and 61 have been shown to the exclusion of any guide or
protective structure. The units 61 and 26 (the outer contours of
which are designated by the broken line 40) have besides been shown
so as to make the valves 72, 73, 74 and 27, 28 and 29 appear
opposite to corresponding actuators 34, 35, 36 and 37, 38 and 39
carried by the tool-carrier frame 30 and remote-controlled by any
known system.
This frame is attached to the end of the column 6 at the level of a
guide and support plate 33 surrounding the collar for connecting
the remote controlled manipulator 7 to the column 6. Once it has
been lowered to the vicinity of the protective structure 76,
precise positioning and connection of the unit 61 to the casing
head is proceeded with. The frame 30 is lowered progressively, the
lower part of it having any kind of impact-dampers as shown
diagrammatically at 56, and let slide along the structure 76 until
it rests on the support plate 75. Supported by a connector like the
connector 10 in FIG. 5, the lower end of the unit 61 is then
centered on the axis of the casing head 17 by any means, for
example, by a connector 70 in FIG. 7 moved hydraulically by remote
control from the surface or by an actuator on the tool-carrier
frame 30, the male portion fitting onto the female portion at the
top of the casing head 17.
This adjustment is enabled by the lateral displacement of the
support and guide plate 33 which in turn is guided and supported by
the plates 81 and 82, and the vertical displacement of jacks 32,
the rods 32a of which control the engagement of the male portion of
the connector 70 in the female portion at the top of the casing
head 17.
Assuming that the unit 61 has been lowered onto the casing head 17
by any one of the foregoing variants, the unit 26 is lowered onto
the unit 61 by means of the frame 30 while supporting this unit by
the remote controlled manipulator 7, the later being connected to
the ship 9 by the column 6. When the frame 30 meets the guide
structure which is associated with it, for example, the arches 79
in FIG. 6, it is guided in such a way that its axis coincides
approximately with that of the axis of the unit 61. The arches 79
may be joined together by a ring member such as ring member 80,
also shown in FIG. 6. The exact squaring up and connection of the
unit 26 on the unit 61 is effected by any means, for example, by a
connector 26a similar to that employed for the connection of the
unit 61 to the casing head 17 and by the action of the jacks 32 and
the plate 33.
With this same tool-carrier frame 30, lowering and attachment of
the two units 26 and 61 can be proceeded with at depth after they
have been previously connected together at the surface, by
performing the same approach and attachment operations with the
unit 61 to the bore-hole head as those which have just been
described.
The system of remote control of, and remote transmission from, the
underwater equipment is put into service in order to establish
control of the equipment from a central control station.
During the erection, satisfactory operation of the units 61 and 26
is checked and, if necessary, the valves 72 to 74 and 27 to 29 are
operated, for example, by means of the actuators 34 to 36 and 37 to
39, which may be controlled by any suitable remote control means.
As these means do not form part of the invention they have not been
shown and it goes without saying that any number of valves can be
so operated.
After checking, the tool carrier frame 30 is drawn up again to the
surface by means of the pipe column 6.
The wellhead installation having been achieved, the well is put
into production from the surface support or from the oilfield well
control and operation installation at the surface, by any kind of
remote control and telemetering means such as those described in
applicants' copending patent application identified above.
In the event of damage to a part of the wellhead or of its becoming
necessary to take action at the well, or at the times planned for
systematic replacement of the unit 26, the intervention operations
are carried out by the same means as those employed for the
installation of the wellhead.
The tool-carrier frame 30 with the manipulator 7 are lowered at the
end of the column 6 and the operations of disconnection of the unit
26 are carried out after guiding and placing the frame 30 onto the
plate 75 in the same fashion as before. Next, closing of the valves
of the units 61 and 26 proceeds by the remote-controlled actuators
34 to 36 and 37 to 39 on the frame 30, and the connector 26a is
disconnected by the same remote control means as used for
connecting up.
The disconnection of the unit 61, which generally is less frequent,
is likewise carried out by means of the tool-carrier frame 30 and
the bell, if the latter was employed for the erection, by
disconnecting the connector 70 form the casing head 17 either by
remote control or manually inside the bell.
In FIG. 8, by way of example, there is shown a jack 41 on the frame
30 for facilitating the withdrawal of the unit 26 after
disconnection, by simple engagement of a cam 43 between two rollers
44 by means of the rod 42, the displacement of the upper roller
bringing about the raising of the unit 26 through the rod 46
slidably mounted in the guides 47.
In applicants' copending patent application identified above it is
described how action can be taken at the well from the ship 9
through the units 26 and 61 without raising the latter.
Although a method has been described which applies to installation
and control of an underwater oilwell head, the invention is not
limited in its sole application to installation of a wellhead but
to any equipment including a separator installation for crude oil
and gas, a pumping station or any underwater installations
consisting of at least a first unit which has to be connected to a
second unit.
* * * * *