Joint bodies and methods for covering electrical cables and connections
A joint body for protecting an electrical cable connection including an electrical cable includes an expandable, elastomeric bladder sleeve and an electrically insulating gel. The bladder sleeve defines a gel cavity and a cable passage to receive the electrical cable. The gel is disposed in the gel cavity and surrounds at least a portion of the cable passage. The joint body is configured to be installed on the connection such that the connection is disposed in the cable passage and is surrounded and electrically insulated by the gel.
1. A joint body for protecting an electrical cable connection including an electrical cable, the joint body comprising:
an expandable, elastomeric bladder sleeve defining a gel cavity and a cable passage to receive the electrical cable; and
an electrically insulating gel disposed in the gel cavity and surrounding at least a portion of the cable passage;
wherein the joint body is configured to be installed on the connection such that the connection is disposed in the cable passage and is surrounded and electrically insulated by the gel;
wherein the bladder sleeve is a double-walled, tubular sleeve defining the gel cavity between the walls thereof; and
wherein the bladder sleeve includes:
an elastomeric, electrically insulating primary bladder layer defining the gel cavity;
an electrically conductive Faraday cage layer integral with the primary bladder layer and forming a part of an inner surface defining the cable passage; and
an electrically conductive stress cone layer integral with the primary bladder layer and forming a part of the inner surface.
2. The joint body of claim 1 wherein the bladder sleeve is radially elastically expandable.
3. The joint body of claim 1 further including an electrically conductive outer screen layer forming an outer surface of the joint body.
4. The joint body of claim 1 including a pressurizing bladder defining a pressurizing chamber sealed off from the gel cavity and adapted to receive a pressurizing material to pressurize the joint body.
5. The joint body of claim 1 wherein the gel is pre-sealed and cured in the gel cavity.
6. The joint body of claim 1 including a removable holdout mounted in the cable passage to maintain the bladder sleeve in an elastically radially expanded state, wherein the holdout is selectively removable from the joint body to permit the joint body to elastically radially contract about the connection.
7. The joint body of claim 1 wherein the bladder sleeve is formed of an elastomeric material selected from the group consisting of EPDM elastomer and silicone elastomer.
8. The joint body of claim 1 wherein the gel is a gel selected from the group consisting of silicone-based gel and hydrocarbon oil-based gel.
9. The joint body of claim 1 wherein the Faraday cage layer and the stress cone layer are embedded in the primary bladder layer.
10. The joint body of claim 1 wherein the primary bladder layer forms a part of the inner surface.
11. A method of protecting an electrical cable connection including an electrical cable, the method comprising:
providing a joint body including:
an expandable, elastomeric bladder sleeve defining a gel cavity and a cable passage to receive the electrical cable; and
an electrically insulating gel disposed in the gel cavity and surrounding at least a portion of the cable passage; and
installing the joint body on the connection such that the connection is disposed in the cable passage and is surrounded and electrically insulated by the gel;
wherein the bladder sleeve is a double-walled, tubular sleeve defining the gel cavity between the walls thereof; and
wherein the bladder sleeve includes:
an elastomeric, electrically insulating primary bladder layer defining the gel cavity;
an electrically conductive Faraday cage layer integral with the primary bladder layer and forming a part of an inner surface defining the cable passage; and
an electrically conductive stress cone layer integral with the primary bladder layer and forming a part of the inner surface.
12. The method of claim 11 wherein installing the joint body on the connection includes:
providing a pre-expanded joint body unit including the joint body mounted on a holdout in an elastically radially expanded state;
positioning the pre-expanded joint body unit adjacent the connection; and thereafter
removing the holdout from the joint body or removing the joint body from the holdout to permit the joint body to elastically radially contract onto the connection.
13. The method of claim 11 wherein:
the joint body includes a pressurizing bladder defining a pressurizing chamber sealed off from the gel cavity; and
the method further includes, after installing the joint body on the connection, injecting a pressurizing material into the pressurizing chamber to pressurize the joint body.
14. The method of claim 11 further including installing an outer sleeve around the joint body on the connection such that the outer sleeve radially constrains the joint body.
15. The method of claim 14 wherein the outer sleeve applies a persistent radially compressive load to the joint body.
16. The method of claim 11 wherein the gel is sealed and cured within the gel cavity prior to the step of installing the joint body on the connection.
17. The method of claim 11 wherein the Faraday cage layer and the stress cone layer are embedded in the primary bladder layer.
18. The method of claim 11 wherein the primary bladder layer forms a part of the inner surface.
19. A protected connection assembly comprising:
an electrical cable connection including an electrical cable; and
a joint body including:
an expandable, elastomeric bladder sleeve defining a gel cavity and a cable passage to receive the electrical cable; and
an electrically insulating gel disposed in the gel cavity and surrounding at least a portion of the cable passage;
wherein the joint body as installed on the connection such that the connection is disposed in the cable passage and is surrounded and electrically insulated by the gel;
wherein the bladder sleeve is a double-walled, tubular sleeve defining the gel cavity between the walls thereof; and
wherein the bladder sleeve includes:
an elastomeric, electrically insulating primary bladder layer defining the gel cavity;
an electrically conductive Faraday cage layer integral with the primary bladder layer and forming a part of an inner surface defining the cable passage; and
an electrically conductive stress cone layer integral with the primary bladder layer and forming a part of the inner surface.
20. The protected connection assembly of claim 19 wherein the connection is a splice connection including an electrical connector and a pair of electrical cables electrically and mechanically coupled by the connector.
21. The protected connection assembly of claim 19 wherein the Faraday cage layer and the stress cone layer are embedded in the primary bladder layer.
22. The protected connection assembly of claim 19 wherein the primary bladder layer forms a part of the inner surface.
23. A method of protecting an electrical cable connection including an electrical cable, the method comprising:
providing a joint body including:
an expandable, elastomeric bladder sleeve defining a gel cavity and a cable passage to receive the electrical cable; and
an electrically insulating gel disposed in the gel cavity and surrounding at least a portion of the cable passage; and
installing the joint body on the connection such that the connection is disposed in the cable passage and is surrounded and electrically insulated by the gel;
wherein the bladder sleeve is a double-walled, tubular sleeve defining the gel cavity between the walls thereof; and
wherein:
the joint body includes a pressurizing bladder defining a pressurizing chamber sealed off from the gel cavity; and
the method further includes, after installing the joint body on the connection, injecting a pressurizing material into the pressurizing chamber to pressurize the joint body.