Information
-
Patent Grant
-
6179585
-
Patent Number
6,179,585
-
Date Filed
Monday, August 24, 199825 years ago
-
Date Issued
Tuesday, January 30, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Walberg; Teresa
- Campbell; Thor
Agents
- Fletcher, Yoder & Van Someren
-
CPC
-
US Classifications
Field of Search
US
- 417 4233
- 417 42315
- 417 4242
- 417 425
- 166 651
- 166 664
- 166 72
- 166 73
- 166 77
-
International Classifications
-
Abstract
A modular plug system facilitates engagement and disengagement of the power cable with a submergible pumping system. The modular plug includes a first plug portion connected to the power cable and mounted within an upper assembly of the connector. The plug also includes a second plug portion connected by a plurality of conductors with the submergible motor. The second plug portion is mounted within a lower assembly of the connector and is configured for mating engagement with the first plug portion. The upper assembly and lower assembly of the connector also are designed for relatively easy engagement and disengagement coincident with the engagement and disengagement of the plug.
Description
FIELD OF THE INVENTION
The present invention relates generally to submergible pumping systems for raising fluids from wells and, particularly, to a selectively engageable connector for connecting a power supply cable to a submergible pumping system.
BACKGROUND OF THE INVENTION
In producing petroleum and other useful fluids from production wells, it is generally known to provide a submergible pumping system for raising the fluids collected in a well. Production fluids enter a wellbore via perforations formed in a well casing adjacent a production formation. Fluids contained in the formation collect in the wellbore and may be raised by the submergible pumping system to a collection point above the earth's surface.
In an exemplary submergible pumping system, the system includes several components, such as a submergible electric motor that supplies energy to a submergible pump. The system may further include additional components, such as a protector, for isolating the motor oil from well fluids. A connector also is used to connect the submergible pumping system to a deployment system. These and other components may be combined in the overall submergible pumping system.
Conventional submergible pumping systems are deployed within a wellbore by tubing, cable, or coiled tubing. Power is supplied to the submergible electric motor via a power cable that runs along the deployment system. For example, with coiled tubing, the power cable is either banded to the outside of the coiled tubing or disposed internally within the hollow interior formed by the coiled tubing.
Power cables typically contain conductors for powering the submergible motor. The motor conductors, typically three conductors, extend along the deployment system to the submergible pumping system where they are hardwired to the motor. The actual conductors may be routed through the connector or alongside the connector.
Regardless of the specific method used for connecting the power cable, the conductors are connected to the motor and the deployment system is attached to the connector prior to deployment of the submergible pumping system. When the conductors of the power cable are connected to the submergible pumping system, the connection point must be prepared carefully to ensure isolation from the relatively hostile environment within a wellbore. For example, if the conductors are routed into the motor, the point of entrance must be rigorously sealed from the fluids and environment in which the submergible motor is disposed. Conventional connection methods for connecting the power cable to the motor are time-consuming and can be subject to failure if careful attention is not paid to sealing any connection points from the wellbore environment.
It would be advantageous to utilize a modular system suited for easy connection of the power cable to the submergible motor or any other components requiring a control input or a communication line.
SUMMARY OF THE INVENTION
The present invention features a connector for connecting a submergible pumping system to a deployment system utilized to deploy the submergible pumping system within a wellbore. The connector is designed with a selectively engageable modular plug system that permits easy attachment of the power cable to the submergible pumping system. Specifically, the connector includes an upper assembly having a plurality of conductors disposed therein. The plurality of conductors terminates at a first plug portion. Additionally, the connector includes a lower assembly having a plurality of corresponding conductors disposed therein. The plurality of corresponding conductors terminates at a second plug portion. The first plug portion and the second plug portion are designed for mating engagement, such that the plurality of conductors form a conductive path with the plurality of corresponding conductors.
According to another aspect of the present invention, a submergible pumping system utilizes a modular connector for easy engagement and disengagement of control lines used for the submergible pumping system. The system includes a string of submergible components, including a submergible motor and a submergible pump. The submergible motor is attached to a plurality of electrical leads which terminate at a first plug portion. The system also includes a deployment system for deploying the string of submergible components. A power cable is disposed along the deployment system and includes a plurality of conductors that supply electrical power to the submergible motor. The plurality of conductors terminates at a second plug portion configured for mating engagement with the first plug portion.
According to yet another aspect of the invention, a method is provided for facilitating connection of control lines to a submergible pumping system. The method comprises connecting a plurality of electrical conductors to a submergible motor of the submergible pumping system. The method also includes providing a split in the plurality of electrical conductors proximate the submergible pumping system. A separable plug may then be attached to the plurality of electrical conductors at the split to permit selective engagement and disengagement of the plurality of electrical conductors.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
FIG. 1
is a front elevational view of a submergible pumping system positioned in a wellbore, according to a preferred embodiment of the present invention;
FIG. 2
is a cross-sectional view of a connector, according to a preferred embodiment of the present invention;
FIG. 3
is a cross-sectional view of a connector and engaged modular plug, according to a preferred embodiment of the present invention;
FIG. 4
is a cross-sectional view of a connector and disengaged modular plug, according to a preferred embodiment of the present invention;
FIG. 5
is a cross-sectional view taken generally along line
5
-
5
of
FIG. 4
;
FIG. 6
is a cross-sectional view taken generally along line
6
—
6
of
FIG. 4
;
FIG. 7
is a cross-sectional view of a connector and modular plug, according to an alternate embodiment of the present invention;
FIG. 8
a
is a cross-sectional view taken generally along line
8
a
—
8
a
of
FIG. 7
;
FIG. 8
b
is a cross-sectional view taken generally along line
8
b
—
8
b
of
FIG. 7
; and
FIG. 9
is a cross-sectional view taken generally along line
9
—
9
of
FIG. 8
a.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring generally to
FIG. 1
, a submergible pumping system
10
is illustrated according to a preferred embodiment of the present invention. Submergible pumping system
10
may comprise a variety of components depending on the particular application or environment in which it is used. However, system
10
typically includes at least a submergible pump
12
and a submergible motor
14
.
System
10
is designed for deployment in a well
16
within a geological formation
18
containing desirable production fluids, such as petroleum. In a typical application, a wellbore
20
is drilled and lined with a wellbore casing
24
. The submergible pumping system
10
is deployed within wellbore
20
to a desired location for pumping of wellbore fluids.
As illustrated, submergible pumping system
10
typically includes other components. For example, a packer assembly
26
may be utilized to provide a seal between the string of submergible components and an interior surface
28
of wellbore casing
24
. Packer assembly
26
may be integrally combined with the string of submergible components, or it can be set in place within wellbore casing
24
before the remainder of submergible pumping system
10
is deployed in well
16
. With packer assembly
26
, production fluids are pumped into the annulus defined by wellbore casing
24
.
Other additional components often comprise a thrust casing
30
, a pump intake
32
, through which wellbore fluids enter pump
12
, a protector
34
, that serves to isolate the well fluid from the motor oil, and a connector
36
. Connector
36
is used to connect submergible motor
14
with a deployment system
38
, such as tubing, cable or coil tubing. In the preferred embodiment, the deployment system is a coiled tubing system
40
utilizing a coiled tube
41
having a power cable
42
running through its hollow center, as will be described in detail below.
It should be noted that a variety of submergible pumping systems
10
can be utilized with the present invention. For example, a variety of motors
14
and pumps
12
can be used, and the production fluids pumped by pump
12
and motor
14
potentially can be pumped through the annulus or through tubing. In either event, an exemplary motor
14
is a three-phase induction-type motor, and an exemplary pump
12
is a multi-staged centrifugal pump. Additionally, other components can be added, components can be removed, or the sequence of components can be rearranged according to the desired application.
Referring generally to
FIG. 2
, a cross-sectional view of connector
36
is taken generally along a longitudinal axis of connector
36
. In the preferred embodiment, connector
36
includes an outer housing
43
having an interior hollow region
44
. Connector
36
, and specifically housing
40
, is connected to the next sequential component of submergible pumping system
10
, preferably motor
14
, by a mounting structure
45
. Mounting structure
45
may be designed for connection to motor
14
and outer housing
43
via a plurality of fasteners
46
, such as bolts.
In the illustrated embodiment, connector
36
includes an upper assembly
48
that engages deployment system
38
. In the illustrated embodiment, upper assembly
48
is connected to coiled tubing
41
. Upper assembly
48
includes a head connector
50
engaged with a housing connector
52
via a threaded region
54
and a sealing ring
56
. Housing connector
52
further includes a radially, outwardly extending flange
58
that declines a notched portion
60
. Notched portion
60
abuts against a lower assembly
62
. A seal
64
is disposed between the upper assembly
48
and lower assembly
62
of outer housing
43
. Additionally, upper assembly
48
and lower assembly
62
preferably are selectively connected by a fastener, such as a union
66
. Union
66
is designed to engage flange
58
of upper assembly
48
and threadably engage a threaded portion
68
of lower assembly
62
.
Lower assembly
62
includes a collar connector
70
having threaded portion
68
disposed along its upper end. Collar connector
70
is engaged with a lower housing connector
72
by a plurality of shear pins
74
and sealed thereto by a seal ring
76
. Thus, if submergible pumping system
10
becomes stuck within wellbore
20
, upper assembly
48
and collar connector
70
may be sheared away from lower housing connector
72
. Lower housing connector
72
may include a plurality of fishing teeth
78
to permit later retrieval of the remainder of submergible pumping system
10
if upper assembly
48
and collar connector are sheared away.
Lower assembly
62
also includes a drain
80
for draining fluids, as necessary, from interior hollow region
44
to wellbore
20
. Drain
80
may have a variety of designs and may be disposed at other locations in outer housing
43
.
With further reference to
FIGS. 3-6
, a primary aspect of the present invention will be explained more fully. Upper assembly
48
and lower assembly
62
may have a variety of configurations, but each configuration preferably includes a modular plugging system to permit power cable
42
to be readily connected to submergible motor
14
and potentially other components in submergible pumping system
10
.
In the preferred embodiment, connector
36
includes a penetrator
82
disposed within hollow region
44
of outer housing
43
. Penetrator
82
includes a separable plug
84
(see FIGS.
3
and
4
). Plug
84
includes a first plug portion
86
that is mounted in upper assembly
48
. Furthermore, plug
84
includes a second plug portion
88
mounted in lower assembly
62
.
A plurality of conductors
90
, from power cable
44
, extend into and are disposed within upper assembly
48
. Conductors
90
terminate in first plug portion
86
. Typically, conductors
90
comprise three conductors for supplying power to motor
14
. Similarly, a plurality of conductors
92
, sometimes referred to as electrical leads, extend into and are disposed in lower assembly
62
. Conductors
92
terminate at second plug portion
88
. Conductors
92
preferably are prewired or preattached to submergible motor
14
. This permits power cable
44
to be connected to submergible motor
14
simply by engaging first plug portion
86
with second plug portion
88
prior to deployment of submergible pumping system
10
in wellbore
20
. (See FIG.
3
). Similarly, the conductive path may be split by separating first plug portion
86
from second plug portion
88
. (See FIG.
4
).
Conductors
92
typically comprise three conductors that may be hardwired to submergible electric motor
14
in a variety of ways known to those of ordinary skill in the art. Preferably, however, conductors
92
are routed through corresponding openings
94
disposed in mounting structure
45
and then connected to submergible motor
14
.
Plug
84
may be designed in a variety of configurations, however, one exemplary configuration is illustrated best in the cross-sectional views of
FIGS. 5 and 6
. In this configuration, first plug portion
86
includes an outer circular wall
96
that extends axially from a transverse wall
98
. A plurality of conductive terminal ends
100
, corresponding with and connected to conductors
90
, extend through transverse wall
98
. Preferably, an annular terminal end housing
102
also extends from transverse wall
98
about each conductive terminal end
100
for at least a portion of the length of the corresponding terminal end. Thus, an annulus
104
is formed between each terminal end
100
and its corresponding terminal housing wall
102
.
Second plug portion
88
also includes an outer circular wall
106
sized to slidingly engage circular wall
96
. For example, the outside diameter of outer circular wall
106
may be slightly less than the inside diameter of circular wall
96
to permit circular wall
106
to be slid within outer circular wall
96
when first plug portion
86
and second plug portion
88
are engaged. Fluid seals, such as o-ring seals, can be disposed between outer circular walls
96
and
106
to secure a liquid-tight seal.
Second plug portion
88
further includes a transverse wall
108
from which a plurality of conductive terminal receptacles
110
extend. Each conductive terminal receptacle
110
includes an inner opening
112
sized to slidingly receive conductive terminal ends
100
such that a conductive path is formed from conductive terminal ends
100
to conductive terminal receptacles
110
. As illustrated, conductive terminal ends
100
are connected with conductors
90
and conductive terminal receptacles
110
are connected with conductors
92
so as to provide appropriate conductive paths from power cable
42
to submergible motor
14
when first plug portion
86
is engaged with second plug portion
88
. Preferably, conductive terminal receptacles
110
are circular in cross-section and sized for reception within the annulus
104
formed between conductive terminal ends
100
and terminal housing walls
102
of first plug portion
86
.
Although the illustrated plug
84
is a preferred embodiment of the invention, a variety of plug configurations could be utilized while still maintaining the modular aspect of a ready-wired plug connection for connecting a power cable to a submergible electrical motor prior to deployment. In the embodiment illustrated, a power cable extending through the center of coiled tubing
41
is securely mounted in upper assembly
48
by an appropriate mounting structure
114
such that conductors
90
may be coupled with first plug portion
86
. Similarly, lower assembly
62
is prewired to submergible electric motor
14
and/or other components within submergible pumping system
10
. Prior to deployment, first plug portion
86
is matingly engaged with second plug portion
88
to form a continuous conductive path from conductors
90
to conductors
92
.
After engaging first plug portion
86
and second plug portion
88
, connector
36
may be firmly coupled together by connecting upper assembly
48
to lower assembly
62
via union
66
. Similarly, when submergible pumping system
10
is retrieved from wellbore
20
, the deployment system is easily disconnected from submergible pumping system
10
. Union
66
simply is unscrewed to permit separation of upper assembly
48
and lower assembly
62
, and thereby separation of first plug portion
86
from second plug portion
88
.
As illustrated in
FIGS. 7-9
, plug
84
can be utilized for facilitating engagement and disengagement of control lines other than the plurality of motor conductors
90
,
92
. An additional control line
116
may be disposed through plug
84
. Control line
116
may comprise one or more of a variety of a control lines, including electrical conductors, optical fibers, and fluid conductors. In any of these implementations, control line
116
is engageable and disengageable at plug portion
84
. For example, control line
116
may have a male portion
118
extending from transverse wall
98
of first plug portion
86
and a female receptacle
120
disposed through transverse wall
108
of second plug portion
88
. Thus, control line
116
may be engaged and disengaged simultaneously with conductors
90
and
92
when plug
84
is engaged and disengaged.
In one preferred embodiment, control line
116
comprises a fluid flow line
122
, as illustrated in
FIGS. 8
a
and
8
b
. Fluid flow line
122
permits fluid, such as hydraulic fluid, to be directed through connector
36
to another component within submergible pumping system
10
. For example, fluid flow line
122
may be routed through plug
84
and connector
36
until it is routed out of connector
36
via an opening
124
. In this particular embodiment, control line
122
is routed along the outside of submergible pumping system
10
to a desired component, such as packer assembly
26
. (See FIG.
1
). In the particular exemplary embodiment, packer assembly
26
is an integral part of submergible pumping system
10
and connected in line with the other components. Fluid control line
122
allows packer assembly to be set at selected locations along the wellbore when submergible pumping system
10
is deployed.
One exemplary way of preparing a connection point for fluid flow line
122
at plug
84
is illustrated best in FIG.
9
. In this adaptation, fluid flow line
122
utilizes a bayonet-style connector. Specifically, control line
116
, e.g. fluid flow line
122
, extends into first plug portion
86
and is sealed to a male adapter
126
. Similarly, fluid flow line
122
extends from the lower side into second plug portion
88
where it is connected to a female adapter
128
that is sized to receive male adapter
126
. Additionally, a pair of seals
130
, such as o-ring seals, are disposed within corresponding grooves
132
formed around male adapter
126
. Seals
130
provide a strong fluid seal between male adapter
126
and female adapter
128
to prevent any leakage of fluid even under substantial pressure.
It will be understood that the foregoing description is of preferred embodiments of this invention, and that the invention is not limited to the specific form shown. For example, a variety of connector components can be used in constructing the connector; one or more control lines can be added in addition to the motor conductors; a variety of control lines, such as fluid control lines, optical fibers, and conductive control lines can be adapted for engagement and disengagement at the plug; the fluid control line can be adapted for delivering fluids, such as corrosion inhibitors etc., to the various components of the submergible pumping system; and the power cable can be routed through coiled tubing or connected along the coiled tubing or other deployment systems. These and other modifications may be made in the design and arrangement of the elements without departing from the scope of the invention as expressed in the appended claims.
Claims
- 1. A connector for connecting a submergible pumping system to a deployment system utilized to deploy the submergible pumping system within a wellbore, comprising:an upper assembly having a first plug portion, the upper assembly being coupleable to a coiled tubing deployment system having a plurality of conductors disposed therein, the plurality of conductors being electrically coupleable to the first plug portion; and a lower assembly coupleable to a submergible pumping system and to the upper assemble, the lower assembly having a plurality of corresponding conductors disposed therein, the plurality of corresponding conductors being electrically coupleable to the second plug portion, wherein the first plug portion and the second plug portion are designed for mating engagement such that the plurality of conductors form a conductive path with the plurality of corresponding conductors.
- 2. The connector as recited in claim 1, wherein the plurality of corresponding conductors comprise motor conductors for connection to a submergible motor within the submergible pumping system.
- 3. The connector as recited in claim 2, wherein the plurality of conductors are three conductors and the plurality of corresponding conductors are three corresponding conductors that contact the three conductors when the first plug portion is engaged with the second plug portion.
- 4. The connector as recited in claim 3, further comprising a conductive control line that extends through the first plug portion and the second plug portion, the conductive control line including a first mating portion disposed in the first plug portion and a second mating portion disposed in the second plug portion to permit separation of the conductive control line when the first plug portion and the second plug portion are disengaged.
- 5. The connector as recited in claim 1, wherein the upper assembly and the lower assembly are selectively attached to one another by a threaded union.
- 6. The connector as recited in claim 1, further comprising a fluid line for conducting fluid, wherein the first plug portion includes a first fluid line end and the second plug portion includes a second fluid line end configured to engage the first fluid line end when the first and the second plug portions are engaged.
- 7. A submergible pumping system utilizing a modular connector for easy engagement and disengagement, comprising:a modular connector assembly having a first connector with a first plug portion and a second connector with a second plug portion, the first connector and second connector being selectively detachable, the first plug portion and second plug portion being configured for mating engagement; a string of submergible components, including a submergible motor and a submergible pump, secured to the first connector, the submergible motor being electrically coupled to the first plug portion; a deployment system secured to the second connector for deploying the string of submergible components; and a power cable for supplying electrical power to the submergible motor, the power cable being electrically coupled to the second plug portion, wherein the plurality of electrical leads of the submergible motor are electrically coupled to the plurality of electrical conductors of the power cable when the first plug portion and second plug portion are matingly engaged, and the string of submergible components is secured to the deployment system when the first connector and the second connector are attached.
- 8. The submergible pumping system as recited in claim 7, wherein the deployment system comprises coiled tubing and the power cable is disposed through a hollow interior of the coiled tubing.
- 9. The submergible pumping system as recited in claim 8, wherein the coiled tubing is attached to the second connector of the modular connector assembly and the plurality of conductors extend through the second connector to the second plug portion.
- 10. The submergible pumping system as recited in claim 9, wherein the plurality of electrical leads extends through the first connector of the modular connector assembly to the first plug portion.
- 11. The submergible pumping system as recited in claim 10, wherein the first connector is connectable to the second connector by a union to hold the first plug portion in engagement with the second plug portion.
- 12. The submergible pumping system as recited in claim 7, further comprising a hydraulic control line extending through the first plug portion and the second plug portion.
- 13. The submergible pumping system as recited in claim 12, wherein the hydraulic control line includes a connector that allows the hydraulic control line to be connected and disconnected as the first plug portion is engaged and disengaged, respectively, with the second plug portion.
- 14. The submergible pumping system as recited in claim 7, further comprising an electrical control line extending through the first plug portion and the second plug portion, the electrical control line being disconnected when the first and the second plug portions are disengaged.
- 15. A method for facilitating connection of control lines to a submergible pumping system, comprising:connecting a plurality of electrical conductors to a submergible motor of the submergible pumping system; providing a split in the plurality of electrical conductors proximate the submergible pumping system; attaching a separable plug to the plurality of electrical conductors at the split to permit selective engagement and disengagement of the plurality of electrical conductors; and connecting the submergible pumping system to a deployment system by a connector and disposing the separable plug within the connector.
- 16. The method as recited in claim 15, further comprising the step of disposing the separable plug within the submergible pumping system.
- 17. The method as recited in claim 15, further comprising the steps of disposing a first plug portion in a lower assembly of the connector; disposing a second plug portion in an upper assembly of the connector; and connecting the lower assembly to the upper assembly by a union.
- 18. The method as recited in claim 17, wherein the step of connecting the submergible pumping system to a deployment system includes utilizing a coiled tubing in which a power cable extends through a hollow interim of the coiled tubing into the connector.
- 19. The method as recited in claim 18, further comprising the step of connecting a fluid control line to the submergible pumping system through a separable fluid control line connector disposed in the separable plug.
US Referenced Citations (12)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2 113 484 |
Aug 1983 |
GB |
2 203 602 |
Oct 1988 |
GB |