WO2004032286A1

WO2004032286A1 - Connector assembly

Info

Publication number: WO2004032286A1
Application number: PCT/SE2003/001558
Authority: WO
Inventors: Allbert Maillard; Nils Wiklund
Original assignee: Allbert Maillard; Nils Wiklund
Priority date: 2002-10-04
Filing date: 2003-10-06
Publication date: 2004-04-15
Also published as: AU2003269758A1; SE0202957D0

Abstract

The present invention relates to a secure cable connector assembly (10), specially for submersible applications, comprising an outer conductive sleeve (17), one or several connector elements (13) provided on an end section of one or several wires (19), a housing (14) for receiving said connector elements (13), said connector assembly being provided for connecting to a corresponding receiving connector (30). The connector assembly further comprises an insulating body (16) provided between at least an end section of said housing (14) and said outer sleeve (17).

Description

Connector Assembly

5 Field of the Invention

The present invention relates to a high strength submersible electrical cable and connector assembly that are described which are particularly suitable for use with submersible applications where the environment is harsh and/or flammable, such as but not limited to ilO submersible pumps that can generate large vibration forces and where the cable and connector are subject to stresses as the cable is moving back and fort thru the water stream during long time of operation.

More specially, the present invention relates to a secure cable connector assembly, specially 15 for submersible applications, comprising an outer conductive sleeve, one or several connector elements provided on an end section of one or several wires, a housing for receiving said connector elements, said connector assembly being provided for connecting to a corresponding receiving connector.

20 Description of the Prior Art

Prior art electric submersible pumps have been used in oil wells to pump well fluids uphole. These types of prior art submersible pumps include electrical connectors for connecting _i electric motors of the pumps to electrical conductors of down hole cables. These pumps are

25 often used in corrosive environments such as wells that produce sour gas, hydrogen sulphide (H₂S). Electrical connectors for electric submersible pumps typically have elastomeric seals. The hydrogen sulphide encountered in sour gas wells will permeate elastomeric seal materials and deteriorate these seals. This allows the gas to migrate back into the electrical connectors, corroding connectors and seriously reducing the service life of 30 downhole pothead connectors and pumps.

In patent literature, for example US 5,377,747 describes an environmentally safe wellhead for wells utilizing electrical submersible pumps which includes an internally tapered casing head into which an externally tapered tubing hanger is closely fitted and sealed. Openings 35 are formed through the tubing hanger parallel to its axis and production tubing is threaded into one of the openings. The power cable for the pump is enclosed in a feedthrough connector disposed and sealed in another of the openings. Tightly fitted metal parts are used and O-ring seals are disposed between the tapered walls of the casing head and hanger as well as between the wall of the opening and the feedthrough connector for the power cable. The feedthrough connector has a metal shell and a separable threadably connected cap member, the interior of which is substantially filled with resilient high dielectric constant material bonded to insulating layers disposed on contacts for the conductors of the cable.

US 6,409,485 describes a sealing system that provides a secure seal against liquid transfer in harsh environments, such as those found in wellbore applications. The sealing system utilizes a connector housing having an axial passage. The interior passage is sized to receive at least a portion of a single support block. The support block is secured to the housing by a retainer, such as a packing gland or a plurality of screws. The single block includes axial openings to individually support and isolate the conductors of a power cable when the power cable is connected to a submersible component

In US6162082 a sealed connector assembly (10) for use with equipment subject to submersion under water is disclosed, which includes two electrical connector shells (25, 29), which are inserted in bayonet fashion into opposite sides of a locking member (40), which is then manually rotated to lock the parts together and shield the electrical connection. The three parts have alignment marks (56, 58, 59) for axial assembly and another mark (57) indicating the rotation of the locking member (40) to a locked position. A body of grease (55) is disposed in one connector shell (25) and an O-ring (50) is placed on the barrel (27) to provide sealing when the connector shells (25, 27) are locked together. The connector shells (25, 29) have wire entry ports and sealing ports for admitting an encapsulating material to seal the wire entry ends. Score lines (68, 69) allow for fracture and removal of the locking member (40) during servicing.

Summery of the invention

The main object of the present invention is to provide a secure connector arrangement, preferably for submersion applications, which does not suffer of the prior art shortcomings and can prohibit short-circuit of a live cable to the housing of the connector.

Another object of the present invention is to provide a leak proof and explosion safe connector, which fulfills safety requirements and is easy to manufacture and assemble. These and other objects are achieved by means of the initially mentioned connector assembly, which further comprises an insulating body provided between at least an end section of said housing and said outer sleeve. Moreover, the assembly comprises a retainer member for detachably attaching said connector assembly to said corresponding receiving connector. The retainer member is arranged to apply a force on said insulating body for deforming the same and obtaining a sealing between said connector and a receiving component. Thus, fulfilling the EX-regulations.

In one preferred embodiment, the retainer member cooperates with a section of said outer sleeve for applying said force. The retainer member is a nut, a bayonet coupling or the like.

In one embodiment, the insulating body is provided with different characteristics at the deformable end section. It may also be provided with a sealing member at the said end.

In most preferred embodiment, each of said one or several connector elements are provided with sealing means between said element and a section of said housing from which the element extends out for providing a sealing. Thus, penetration of fluid into the receiving connector is prevented.

Preferably, the insulating body is made of an elastic material, such as rubber and the outer sleeve is made of a rigid material being one of steel, iron, copper, etc.

Most preferably, said corresponding receiving connector is arranged on a submersible component, which can be a pump.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with further objects, aspects, features and advantages thereof, will become more fully understood from a consideration of the following detailed description taken in conjunction with the accompanying drawings, in which:

Fig. 1 is cross-sectional view through one exemplary embodiment of a connector assembly according to the invention, and Figs. 2-4 are enlarged views illustrating indicated parts of the embodiment according to Fig. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following, the invention is described with reference to an exemplary embodiment comprising a submersible pump, it is clear that the connector according to the invention can be used in any electrical coupling applications having use of the advantages presented by the connector of the invention.

Figs. 1-4 illustrate cross-sectional views of a connector assembly 10 (male) connected to a receiving connector 30 (female) arranged on a housing of a submersible pump 40. Figs. 2 - 4 are enlarged views.

The connector assembly 10 receives at one end a cable 11, which houses wires 12 and comprises pin contacts 13 at end of each wire of the cable, pin contact holder 14, pin contact O-rings 15, insulating cover 16, outer sleeve 17 and a nut 20, e.g. an X-nut.

Each wire 12 is provided with an insulating cover 19 covering a conductive core 18. One end of each wire inserted into the connector is stripped and provided with the pin connector 13, in a conventional way. Wires 12 are arranged inside the cable and provided with insulating spacers 28, well known for a skilled person.

The connector assembly 10 comprises a first outer sleeve 17 of a rigid material, for example steel, which at least partly encloses the insulating cover 16, made of a substantially elastic material such as rubber. It is important that the outer sleeve is not inflammable, why metallic sleeves are frequently used.

Amongst others, because of the rigidity of the cable, the cable 12 is normally stripped and have a distance (A) between the non-stripped end and the closest end of the contact pin holder 14. Consequently, there is a risk that a loosen live wire (loosened due to vibration, pulled out, etc) comes into contact with the outer sleeve, which is made of a conductive material. The outer sleeve 17 protects the connector, while the insulating cover besides protecting the section between the outer sleeve and the cable also prohibits a possible contact between a wire and the outer sleeve, if one of the wires loosens. Thus, the insulating cover must have a substantial length to cover inside of the outer sleeve so that no contact between a loosened wire and the outer sleeve is possible.

The nut 20 is provided to attach the contact assembly to the pump housing. It is threaded 21 at one end for co-operation with a threaded section of the pump housing. According to this embodiment, threaded end has a substantially semi-conical end 20', which co-operates with a similar outer surface 17' of the outer sleeve and lucks the entire connector assembly to the pump housing. When the substantially conical end 20' of the nut 20 in cooperation with substantially conical surface 19' of the outer sleeve 19 presses the outer sleeve towards the pump housing, the end section of the insulating cover, covered by the outer sleeve is forced against the housing of the pump (best seen in figs. 2 and 3) such that the insulating cover is deformed (crimped) at and seals the column 22 between the pin contact holder 14 and the housing 40, thus preventing penetration of fluid/moisture through the column into the connection area. It is also possible to arrange the pressing end 16' of the cover 16 as a separate washer or made of a material having different characteristics (better elasticity) than the rest of the cover.

Explosion protection regulations of the EU member states are marked by EU guideline 94/9/EG (ATEX 100a) and 95/C 332/06 (ATEX 118a). The connector arrangement of the invention fulfils the regulations as the sealing obtained by means of the insulating cover seals the spaces between the outer sleeve/pump body and outer sleeve/pin contact holder.

It is obvious that the nut 20 and the interacting sections of nut and the outer sleeve are given as an example and other nut types and interacting shapes can occur, such as a bayonet coupling or the like.

There is also a risk that the cover of the cable leaks fluid into the cable and thus the connector because of age and tear-and-wear. The pin connectors extend out of the holder 14 through corresponding holes at one end of the holder, and are secured against axial displacement by means of locking tongues 13'. Additional security is achieved by providing the pin connectors 13 before extending out of the holes in the holder 14 with o-rings 15, which prevent penetration of fluid/moisture through the wires. Projections 13" prevent both displacement of the pins and o-rings in axial direction. Of course, other sealing than o-rings can be provided.

Thus, the invention provides a safe and improved connector arrangement, which gives better isolation against liquid (specially water or oil) leakage, short-circuiting, high pressure and explosion.

The connector 30 of the pump is of a conventional type and comprises a housing 33 holding contact pins 32 and incoming wires 31.

The invention is not limited to the shown embodiments but can be varied in a number of ways without departing from the scope of the appended claims and the arrangement and the method can be implemented in various ways depending on application, functional units, needs and requirements etc.

Claims

1. A secure cable connector assembly (10), specially for submersible applications, comprising an outer conductive sleeve (17), one or several connector elements (13)

5 provided on an end section of one or several wires (19), a housing (14) for receiving and retaining said connector elements (13), said connector assembly being provided for connecting to a corresponding receiving connector (30), characterized in that said connector assembly further comprises an insulating body (16) provided between at 10 least an end section of said housing (14) and said outer sleeve (17).

2. The connector assembly of claim 1 ⁽ characterized in that said assembly comprises a retainer member (20) for detachably attaching said 15 connector assembly to said corresponding receiving connector (30), and that said retainer member is arranged to apply a force on said insulating body (16) for deforming at least an end section of the same and obtaining a sealing between said connector and a receiving component (40).

20 3. The connector assembly of claim 2, characterized in that said retainer member cooperates with a section (17') of said outer sleeve for applying said force.

I

25 4. The connector assembly of claim 2 or 3, characterized in ι that said retainer member is a nut, a bayonet coupling or the like.

5. The connector assembly according to any of claims 2-4, 30 characterized in that said insulating body is provided with different characteristics at the deformable end.

6. The connector assembly according to any of claims 2-4, characterized in

35 that said insulating body is provided with a sealing member (16") at the deformable end.

7. The connector assembly according to any of claims 1-6, characterized in that each of said one or several connector elements (13) are provided with sealing means (15) between said element and a section of said housing from which the element extends out for providing a sealing.

8. The connector assembly according to any of preceding claims, characterized in that said insulating body is made of an elastic material, such as rubber.

9. The connector assembly according to any of preceding claims, characterized in that said outer sleeve is made of a rigid material being one of steel, iron, copper, etc.

10. The connector assembly according to any of preceding claims, characterized in that said corresponding receiving connector (30) is arranged on a submersible component (40).

11. The connector assembly of claim 10, characterized in that said component is a pump.