Abstrict An apparatus and a method for its use allow selective installation
and removal of a canister such as one containing interface electronics
to a mating connector on a housing, such as one containing a subsea
multiphase flow meter sensor. The separately retrievable canister
may contain multiphase flow meter detector electronics and is sealed,
waterproof, and preferably light-weight. Installation and retrieval
may be via use of an ROV and an alignment guide which acts as a
guide to aid in correct positioning of the canister. The canister
may be cooled by surrounding sea water and/or by insulation. It
is emphasized that this abstract is provided to comply with the
rules requiring an abstract which will allow a searcher or other
reader to quickly ascertain the subject matter of the technical
disclosure. It is submitted with the understanding that it will
not be used to interpret or limit the scope of meaning of the claims.
Claims What is claimed is:
1. A subsea multiphase flow meter sensor housing, comprising: a.
a flow tubular housing; and b. a retrievable canister, adapted to
be removably attached to the flow tubular housing and to house electronics.
2. The subsea multiphase flow meter sensor housing of claim 1
wherein the electronics comprise a multiphase flow meter detector.
3. The subsea multiphase flow meter sensor housing of claim 2
wherein: a. the multiphase flow detector is self-contained and further
comprises at least one of (i) a self-contained power unit or (ii)
a central processing unit adapted to calculate fluid flow from transmission
of data received through a flow meter sensor housing mating connector;
and b. the multiphase flow detector is further adapted to allow
for local or remote transmission or recording of fluid flow in the
flow tubular housing.
4. The subsea multiphase flow meter sensor housing of claim 1
wherein: a. the retrievable canister further comprises a connector
disposed on an exterior surface area of the retrievable canister,
the connector in communication with the electronics; and b. the
flow tubular housing further comprises a flow tubular housing connector
adapted to provide a watertight mating with the retrievable canister
connector and provide for communication between the electronics
and a device.
5. The subsea multiphase flow meter sensor housing of claim 4
wherein the flow tubular housing connector and the retrievable canister
connector are adapted to accommodate at least one of (i) an electrical
interface, (ii) a fiber optic interface, or (iii) an acoustic interface.
6. The subsea multiphase flow meter sensor housing of claim 1
wherein retrievable canister is at least one of (i) sealed, (ii)
waterproof, or (iii) light-weight.
7. The subsea multiphase flow meter sensor housing of claim 1
wherein: a. the flow tubular housing comprises an alignment guide
adapted to accept the retrievable canister; and b. the retrievable
canister further comprises a selectively engageable lock adapted
to secure the retrievable canister to the flow tubular housing.
8. The subsea multiphase flow meter sensor housing of claim 7
wherein the selectively engageable lock is adapted to be operated
by a remotely operated vehicle ("ROV") without the use
of a light intervention tool.
9. The subsea multiphase flow meter sensor housing of claim 7
wherein: a. the selectively engageable lock is disposed proximate
a first end of the retrievable canister opposite; and b. an interface
connector in communication with the multiphase flow detector electronics
is disposed proximate an end of the retrievable canister distal
from the selective engagement connector.
10. The subsea multiphase flow meter sensor housing of claim 7
wherein: a. the alignment guide comprises a volume larger than the
volume of the water-tight canister; and b. the alignment guide generally
conforms to the three-dimensional shape of the water-tight canister.
11. The subsea multiphase flow meter sensor housing of claim 7
wherein: a. the alignment guide is adapted to aid in positioning
the retrievable canister into position; and b. the alignment guide
is further adapted to aid in positioning the selectively engageable
lock.
12. The subsea multiphase flow meter sensor housing of claim 7
wherein: a. the alignment guide is substantially funnel shaped;
and b. the alignment guide is adapted to allow locking of the retrievable
canister to the alignment guide using the selectively engageable
lock.
13. The subsea multiphase flow meter sensor housing of claim 1
wherein the retrievable canister is adapted to be cooled by at least
one of (i) surrounding sea water, (ii) insulation, or (iii) both
insulation and surrounding sea water.
14. The subsea multiphase flow meter sensor housing of claim 1
wherein the retrievable canister further comprises an environment
of a predetermined pressure maintained with an inert gas.
15. The subsea multiphase flow meter sensor housing of claim 14
wherein the predetermined pressure maintained with an inert gas
is around one atmosphere.
16. A method of mating a retrievable canister to a stationary section
of a multiphase flow meter, comprising: a. using a remotely operated
vehicle (ROV) to position a retrievable canister into an alignment
guide located proximate a flow tubular housing; b. guiding the retrievable
canister to a position wherein a connector on the retrievable canister
is proximate a mating connector on a stationary portion of the flow
tubular housing; c. engaging a locking mechanism by the ROV to secure
the retrievable canister to the stationary portion of a flow tubular
housing.
17. The method of claim 16 further comprising: a. disengaging
the locking mechanism by the ROV to unsecure the retrievable canister
from the stationary portion of a flow tubular housing; and b. retrieving
the retrievable canister from the stationary portion of a flow tubular
housing using the ROV.
18. The method of claim 17 wherein engaging the locking mechanism
further engages the connector on the retrievable canister to the
mating connector on the stationary portion of the flow tubular housing
to establish communications between electronics disposed within
the retrievable canister and a predetermined device external to
the retrievable canister.
19. The method of claim 18 wherein engaging further comprises
turning the lock approximately 90 degrees to engage the locking
mechanism.
Description RELATION TO OTHER APPLICATIONS
[0001] This application claims priority through U.S. Provisional
Patent Application No. 60/566701 filed on Apr. 30 2004.
FIELD OF THE INVENTION
[0002] This invention relates to a subsea device and more particularly
to a retrievable subsea multiphase fluid flow meter wherein a method
of and apparatus for engaging or disengaging a water-tight canister
containing the flow meter electronics is utilized.
BACKGROUND OF THE INVENTION
[0003] Multiphase flow meters in the oil and gas industry are commonly
used for topside (non-subsea) applications. Subsea non-retrievable
multiphase flow meters are also common which have little or no distinguishing
features from topside multiphase flow meters other than a water-proof
design and/or remotely deliverable electrical and hydraulic power
connections.
[0004] Existing subsea retrievable multiphase flow meters include
complex and expensive stationary inlet and outlet sections in which
the multiphase flow meter detector electronics are non-detachable.
[0005] Existing subsea retrievable multiphase flow meters have
the disadvantage of non-detachably housing the flow meter detector
electronics such that removal of the entire meter is required to
service or repair it, causing significant downtime and expense.
[0006] Typical multiphase subsea oil and gas flows at high temperatures
which detrimentally effects the multiphase flow detector electronics
by reducing its mean time before failure. Existing subsea retrievable
multiphase flow meters have the disadvantage of not providing an
inexpensive cooler for stabilizing the multiphase flow detector
electronics and thereby improving mean time before failure.
SUMMARY OF THE INVENTION
[0007] The present inventions relate to a apparatus and a method
for allowing a subsea multiphase flow meter sensor housing directly
attached to, but detachable from, a separately retrievable canister
containing multiphase flow meter detector electronics. The retrievable
canister is sealed, waterproof and may be light-weight. In one embodiment,
the retrievable canister may be retrieved and installed through
an alignment guide which acts as a guide to aid in correct positioning
by the novel use of a remotely operated vehicle ("ROV")
without the use of a light intervention tool. A specially designed
connector disposed on an exterior surface area of the removable
canister provides one or more connections between the multiphase
flow detector electronics disposed in the interior of the canister
and the flow meter sensor housing mating connector.
[0008] The removable canister may be cooled by surrounding sea
water, which may stabilize the temperature of the flow detector
electronics and may improve equipment and component mean time before
failure. In another embodiment, the removable canister is insulated
and additionally cooled by the surrounding sea water which may stabilize
the temperature of the flow detector electronics and may improve
equipment and component mean time before failure.
[0009] The scope of protection is not limited by the summary of
an exemplary embodiment set out above, but is only limited by the
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] A better understanding of the present invention can be obtained
when the detailed description set forth below is reviewed in conjunction
with the attached drawings depicting various embodiments of the
present invention. The attached drawings are incorporated herein
as if set out in full.
[0011] FIG. 1 is a perspective view of an embodiment of the present
inventions;
[0012] FIG. 2 is a cutaway view of an embodiment of the present
inventions;
[0013] FIG. 3 is a perspective view of an embodiment of the present
inventions; and
[0014] FIG. 4 is a perspective view of an embodiment of a retrievable
canister of the present inventions.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0015] Referring now to FIG. 1 retrievable canister 30 is removably
secured to multiphase flow meter 10 which comprises flow tubular
housing 20 and alignment guide 40. Fluid flowing within multiphase
flow meter 10 can be single or multiphase and be oil, water or gas,
or any combination thereof, as well as any similar type of fluid
or combination.
[0016] Flow meter housing 10 may comprise flow tubular housing
20 and alignment guide 40.
[0017] Referring to FIG. 2 either flow tubular housing 20 or alignment
guide 40 comprises flow meter sensor housing mating connector 22.
Flow meter sensor housing mating connector 22 provides for further
communication with one or more devices (not shown in the figures)
disposed on, near, or within flow tubular housing 20 of multiphase
flow meter 10 e.g. for transmission of power and data or control
signals.
[0018] Retrievable canister 30 which is preferably water-tight,
comprises an exterior surface area and an interior volume. Electronics
(not shown in the figures), e.g. fluid flow detector electronics,
may be disposed within an interior volume of retrievable canister
30 in any of numerous conventional ways as will be familiar to those
of ordinary skill in the subsea instrumentation arts. In an embodiment,
retrievable canister 30 may comprise a substantially cylinder shape,
e.g. having spherical or obround ends. Retrievable canister 30 comprises
connector 32 adapted to provide a water-tight connection to flow
meter sensor housing mating connector 22 and thus further between
its interior electronics and one or more devices (not shown in the
figures) disposed on, near, or within flow tubular housing 20 of
multiphase flow meter 10 e.g. for transmission of power and data
or control signals.
[0019] Canister 30 uses a locking mechanism 33 shown in an exemplary
embodiment in FIG. 4 as handle 34 hub 35 and locking pins 36 and
27 to be secured to multiphase flow meter 10. Locking mechanism
33 is disposed on the exterior surface area of retrievable canister
30 and may be selectively engaged or disengaged to selectively secure
retrievable canister 30 to multiphase flow meter 10 to mate connector
32 with flow meter sensor housing mating connector 22. Locking mechanism
33 may be disposed on an end of retrievable canister 30 opposite
connector 32.
[0020] In the exemplary embodiment illustrated in FIG. 4 locking
mechanism 33 operates by pivotally mounting locking pins 36 and
37 to hub 35 which is rotatably mounted about a center axis and
adapted to move axially in either direction upon rotary motion of
handle 34. Movement in a direction, e.g. circumferentially, forces
pins 36 and 37 to extend from hub 35 and movement in the opposite
direction forces pins 36 and 37 to retract. Pins 36 and 37 may align
with corresponding mating receivers, e.g. receivers (not shown in
the figures) in Flow meter housing 10. Once hub 35 is rotated to
a desired position, hub 35 may be locked into that position by any
of numerous, equivalent methods as will be known to those of ordinary
skill in these arts. One or more additional latches or locking mechanisms
may be present, e.g. as mating portions of connector 32 and flow
meter sensor housing mating connector 22.
[0021] Referring additionally back to FIG. 1 alignment guide 40
maybe attached to flow tubular housing 20 or be integral with flow
tubular housing 20 i.e. multiphase flow meter 10 may be a unitary
device comprising both flow tubular housing 20 and alignment guide
40. Alignment guide 40 will typically comprise a volume greater
than the volume of canister 30 and may further generally conform
to the three-dimensional shape of canister 30.
[0022] Alignment guide 40 may act as an aid to positioning retrievable
canister 30 and its locking mechanism 33 when inserting retrievable
canister 30 into, and attaching, or disconnecting and retrieving
retrievable canister 30 from flow meter sensor housing 10 including
engaging connector 32 with or disengaging connector 32 from flow
meter sensor housing mating connector 22.
[0023] Referring additionally to FIG. 3 for proper alignment and
orientation of retrievable canister 30 during a subsea mating operation,
alignment guide 40 comprises guide funnel 42 or other a substantially
conical opening to receive retrievable canister 30.
[0024] Retrievable canister 30 may be locked to either stationary
portion 30 or alignment guide 40 e.g. to guide funnel 42. Retrievable
canister 30 when locked into position, e.g. using locking mechanism
33 forms a water-tight seal between connector 32 and flow meter
sensor housing mating connector 22. A mechanical locking mechanism
(not shown in the figures) that maintains retrievable canister 30
in position after mating may be present at a second end of retrievable
canister 30.
[0025] In an embodiment, retrievable canister 30 comprises an exterior
shell comprising a metal suitable for use subsea to protect its
inner electronics from intrusion of sea water. In a preferred embodiment,
the exterior shell protects the inner electronics from intrusion
of sea water at depths up to at least 3000 meters. Internally, retrievable
canister 30 may have an environment comprising a predetermined pressure
maintained with an inert gas such as Nitrogen, e.g. around one atmosphere.
[0026] In an embodiment, retrievable canister 30 is insulated from
its external environment which may improve equipment and component
mean time before failure.
[0027] In the operation of exemplary embodiments, a method of mating
a retrievable canister 30 to stationary section 20 of multiphase
flow meter 10 is accomplished by using a remotely operated vehicle
("ROV") subsea (not shown in the figures). In this method,
retrievable canister 30 is positioned by an ROV into alignment guide
40. A 90 degree turn may be required by the ROV to engage the locking
mechanism.
[0028] The remote engagement or disengagement of the water-tight
canister locking mechanism may be accomplished by using a light
intervention tool or by using a ROV to position retrievable canister
30 into alignment guide 40. The ROV then guides retrievable canister
30 to a position wherein connector 32 is proximate mating connector
22. Once positioned, locking mechanism 33 is engaged by the ROV
to secure retrievable canister 30 to stationary portion 20 of flow
tubular housing 10.
[0029] To retrieve retrievable canister 30 locking mechanism 33
is disengaged by the ROV to unsecure retrievable canister 30 from
stationary portion 20 of flow tubular housing 10 and retrievable
canister 30 retrieved from stationary portion 20 of flow tubular
housing 10 by the ROV.
[0030] Typically, engaging locking mechanism 33 further engages
connector 32 to mating connector 22 to establish communications
between electronics disposed within retrievable canister 30 and
one or more predetermined devices external to retrievable canister
30 this manner, a device disposed outside retrievable canister 30
e.g. a fluid flow detector (not shown in the figures) disposed within
or proximate flow tubular 10 is operatively connected to electronics
disposed within retrievable canister 30 e.g. a flow meter. This
allows communication between these devices and receives data transmitted
by sensors from the flow meter sensor housing mating connector after
the locking mechanism is engaged. The data transmission, and, hence,
the connection, may be electronic, fiber optic, acoustic, or the
like, or a combination thereof. The fluid flow detector is self-contained
and may utilize a self-contained power unit, a central processing
unit to calculate the fluid flow from the transmission of data received
from the flow meter sensor housing mating connector, or the like,
or a combination thereof. The central processing unit may use a
computer software flow algorithm to calculate the fluid flow. The
fluid flow detector may also allow for the local or remote transmission
or recording of the calculated fluid flow.
[0031] The foregoing disclosure and description of the invention
are illustrative and exemplary thereof, and various changes in the
size, shape and materials, as well as in the details of the illustrated
construction, may be made without departing from the spirit of the
invention. |