NZ623196B2 - Bushings, sealing devices, tubing, and methods of installing tubing - Google Patents

Abstract

bushing (306) for metal pipe connections is disclosed. The bushing comprises one or more circumferential ribs (see 326a & 326b; figure 3C) adapted to engage one or more corrugations of a tube (200; see also figure 3C), and one or more axially extending tongues (312a) located on a substantially opposite end of the bushing from the one or more circumferential ribs. The one or more axially extending tongues are tapered toward an end of the bushing to allow easier insertion of the one or more axially extending tongues between tube layers (see 204, 206, 208; figure 3C). The bushing is fabricated from a conductive material and the one or more axially extending tongues are adapted to form electrical continuity with the tube. osite end of the bushing from the one or more circumferential ribs. The one or more axially extending tongues are tapered toward an end of the bushing to allow easier insertion of the one or more axially extending tongues between tube layers (see 204, 206, 208; figure 3C). The bushing is fabricated from a conductive material and the one or more axially extending tongues are adapted to form electrical continuity with the tube.

Description

BUSHINGS, G DEVICES, TUBING, AND METHODS OF INSTALLING TUBING CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to U.S. Provisional Patent Application Serial No. 61/544,516, filed October 7, 2012. The entire contents of this application are hereby orated by reference herein.

FIELD OF INVENTION The present invention relates to gas, liquid, and slurry piping systems as well as protective conduit systems for cable carrying purposes, and more particularly to bushings, sealing devices, tubing, methods of installing tubing incorporating fittings capable of transferring and dissipating energy.

BACKGROUND OF THE INVENTION Gas and liquid piping s utilizing corrugated stainless steel tubing (“CSST”) and fittings are known. Such piping systems can be designed for use in combination with ed pressures of up to about 25 psi or more and provide ages over traditional rigid black iron piping systems in terms of ease and speed of installation, elimination of onsite measuring, and reduction in the need for certain fittings such as elbows, tees, and couplings. Undesirably, the thin metal walls are vulnerable to failure when exposed to physical or electrical forces, such as lightning or fault currents.

Often, electrical currents will occur inside a ure. These ical currents, which can vary in duration and magnitude, can be the result of power fault currents or induced currents ing from ing ctions with a house or structure. The term “fault t” is typically used to describe an overload in an electrical system, but is used broadly herein to include any electrical current that is not normal in a ic system. These currents can be the result of any number of situations or events such as a lightning event. Electrical currents from lightning can reach a structure ly or indirectly. Direct currents result from lightning that attaches to the actual structure or a system contained within the structure. When current from a nearby lightning stroke moves through the ground or other conductors into a structure, it is referred to as indirect current. While both direct and indirect currents may enter a structure through a particular system, voltage can be induced in other systems in the structure, especially those in close proximity to piping systems.

This can often result in an electrical ver or arc between the adjacent systems. A flashover occurs when a large voltage differential exists between two electrical conductors, causing the air to ionize, the material between the conductive bodies to be red by the high voltage, and formation of a spark.

It usually takes a very large voltage differential to create a flashover through a good dielectric material. When a flashover does occur, the flow of electrons through the ionized path causes energy dissipation h heating and a shockwave (i.e. , sound). The extent of heat and shock is ly related to the duration and ude of the electrical energy in the flashover. ntly, the voltage required to breakdown a dielectric material is enough to drive a relatively large amount of energy across the associated spark often resulting in damage to both conductors and any material between them. The primary mode of failure is extreme heating and melting of these materials.

Metals are electrically conductive materials, making CSST a very good pathway for electrical currents. This leads to the potential for a flashover if the CSST is installed in close ity to another conductor within a structure and either one becomes energized. A flashover like this is often the result of a lightning event but it is foreseeable that other events may also be capable a producing a sufficient voltage differential between conductors. It is possible that a flash like this can cause enough heat generation to melt a hole in the CSST, allowing fuel gas to escape. This scenario is worsened by the dielectric jacket that often surrounds CSST. This jacket typically breaks down in a very small area, creating a pinhole as a result of the flashover. This phenomenon focuses the flash and concentrates the heating of the stainless steel inside. The result is a d capability of the CSST to resist puncture from flashover compared to un-jacketed pipe.

Accordingly, it would be desirable to e corrugated tubing and sealing devices having an increased resistance to physical and ical forces that approaches that of tional black iron pipe. atively it is an object to at least provide the public with a useful choice.

SUMMARY OF THE INVENTION Bushings, sealing devices, tubing, and methods of ling tubing are provided.

A first aspect of the invention provides a bushing comprising: one or more substantially circumferential ribs adap ted to engage one or more ations of a tube; one or more axially-extending tongues located on a substantially opposite end of the bushing from the one or more substantially circ umferential ribs, wherein the one or more axially-extending tongues are tapered towar d an end of the bushing; wherein the g is fabricated from a conductive al; and wherein the one or more axially-extending tongues a re adapted and configured to form electrical continuity with the tube.

This aspect of the invention can have a variety of embodiments. The bushing can be a split bushing. The bushing can be a two-piece bushing. The g can include two halves coupled by a living hinge. The bushing can include at least two axially-extending tongues. The one or more axially-extending tongues can have a substantially semi-circular profile.

The one or more axially-extending tongues can be tapered toward an end of the bushing.

The one or more axially-extending tongues can have a taper angle of between about 1º and about 4º. The one or more y-extending tongues can have a taper angle of between about 2º and about 3º.

The bushing can be fabricated from a conductive al. The conductive material can be a metal. The metal can be selected from the group consisting of: aluminum, copper, gold, iron, silver, zinc, and an alloy thereof. The alloy can be selected from the group consisting of brass, bronze, steel, and stainless steel.

The g can further include one or more substantially circumferential ribs adapted to engage one or more corrugations of a tube. The one or more ntially circumferential ribs can be located on a substantially opposite end of the bushing from the one or more axially-extending tongues.

The tube can be corrugated. The tube can be corrugated stainless steel tubing.

The one or more axially-extending tongues can be adapted to form electrical continuity with the tube. The tube can include one or more conductive jacket layers and the one or more y-extending tongues can be adapted to form electrical uity with at least one of the one or more conductive jacket layers. (followed by 3a) Another aspect of the ion provides a sealing device for connecting a length of tubing, the sealing device comprising: a body member defining a sleeve portion; and the bushing of the first aspect of the invention adapted and configured to be ed in the sleeve portion, n the one or more axially-extending tongues are adapted and configured to be received over at least one layer of the tubing.

This aspect of the ion can have a variety of embodiments. The sealing device can further include a nut adapted and configured for threaded coupling with the body member. The bushing and the nut can be dimensioned such that as the nut is tightened, the one or more tongues are compressed against the tubing by the nut. (followed by 4) The tubing can include a jacket. The bushing and the nut can be dimensioned such that as the nut is tightened, one or more layers of the jacket are compressed between an or surface of the nut and an exterior surface of the one or more tongues.

The bushing and the nut can be dimensioned such that as the nut is tightened, the one or more tongues are compressed against one or more layers of the jacket by the nut.

The nut can have an external thread and the sleeve portion of the body member can have a complimentary internal thread.

The nut can have a tapered inner surface.

The nut can include a torque-limiting feature. The torque-limiting e can be a shear point. r aspect of the invention provides a length of tubing comprising: an inner tubing layer; and a fitting coupled to an end of the tubing, the fitting including: a body member defining a sleeve portion; and the bushing of the first aspect of the invention ing lly over at least the inner tubing layer and received along with at least the inner tubing layer in the sleeve portion, wherein the one or more axially-extending tongues are adapted and ured to be received over the inner tubing layer.

This aspect of the invention can have a variety of embodiments. The length of tubing can further include a conductive layer surrounding the outside of the inner tubing layer. The one or more tongues can be in t with the conductive layer.

The one or more tongues can be positioned n the inner tubing layer and the conductive layer. The length of tubing can further e an outer tubing layer surrounding the outside of the conductive layer. The one or more tongues can be positioned between the conductive layer and the outer tubing layer. The inner tubing layer can be metallic tubing. The inner tubing layer can be thin-walled tubing. The inner tubing layer can be le tubing. The inner tubing layer can be corrugated tubing. The outer tubing layer can be a resin layer.

The conductive layer can include a metal. The metal can be selected from the group consisting of: aluminum, copper, gold, iron, silver, zinc, and an alloy thereof.

The alloy can be selected from the group consisting of brass, bronze, steel, and stainless steel. The metal can be a metal foil. The metal foil can completely surround the inner tubing layer. The metal foil can be an expanded metal foil. The metal can be one or more metal wires. The conductive layer can comprise a conductive resin.

The length of tubing can further e an inner resin layer positioned between the inner tubing layer and the conductive layer.

Another aspect of the invention provides a method of installing energy dissipative tubing, the method comprising: providing a length of tubing including: an inner tubing layer; providing a sealing device including a body member defining a sleeve portion and the bushing of the first aspect of the invention; placing the bushing over at least the inner tubing layer such that the one or more y-extending tongues are positioned over the inner tubing layer; and inserting the g and at least the inner tubing layer into the sleeve portion.

This aspect of the invention can have a variety of embodiments. The method can include coupling the g device to a device selected from the group consisting of: a pipe, a manifold, a meter, a gas main, a tank, and an appliance. The pipe can be black iron pipe. The appliance can be selected from the group ting of: a stove, an oven, a grill, a furnace, a clothes dryer, a fireplace, and a generator.

The length of tubing can e a conductive layer surrounding the outside of the inner tubing layer. The one or more tongues can be oned in contact with the conductive layer. The one or more tongues can be oned between the inner tubing layer and the conductive layer.

The length of tubing can include an outer tubing layer surrounding the outside of the conductive layer. The one or more tongues can be positioned between the conductive layer and the outer tubing layer.

The method can further include tightening a nut to advance the bushing. The step of tightening a nut can includes tightening the nut until a torque-limiting portion of the nut shears.

Unless the context clearly requires otherwise, throughout the description and claims the terms “comprise”, “comprising” and the like are to be construed in an ive sense, as opposed to an exclusive or exhaustive sense. That is, in the sense of “including, but not limited to”. (followed by 5a) BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the nature and desired objects of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawing figures wherein like reference characters denote corresponding parts throughout the several views and wherein: depicts a multi-layer jacketed tube in ance with the prior art. depicts an energy dissipative tube in ance with the prior art. (followed by 6) FIGS. 3A—3F depict embodiments of a sealing device and tubing assembly in accordance with preferred embodiments of the invention.

FIGS. 4A—4D depict a nut including a —limiting feature in accordance with a preferred embodiment of the invention. depicts a method for installing tubing in accordance with a preferred embodiment of the invention.

DEFINITIONS The instant invention is most clearly understood with reference to the following definitions: As used herein, the singular form “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.

Unless specifically stated or obvious from context, as used herein, the term “about” is understood as within a range of normal tolerance in the art, for example within 2 standard deviations of the mean. “About” can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear from context, all numerical values provided herein are modified by the term about.

As used herein, the term “alloy” refers to a nous mixture or metallic solid solution composed of two or more elements. Examples of alloys e austentitic nickel—chromium—based superalloys, brass, bronze, steel, low carbon steel, phosphor bronze, stainless steel, and the like.

As used in the specification and , the terms “comprises,79 6‘comprising,” “containing,” “having,” and the like can have the meaning ed to them in US. patent law and can mean “includes,” “including,” and the like.

As used herein, the terms “corrugated stainless steel tubing” and “CSST” refer to any type of tubing or piping, which may accommodate corrosive or aggressive gases or s, and includes but is not limited to tubing or piping made from: thermoplastics, metal or metal alloy materials such as olefin—based cs (e.g., hylene (PE)), fluorocarbon rs (e.g., polytetrafluoroethylene (PTFE)), carbon steel, , brass, aluminum, titanium, nickel, and alloys thereof.

Unless specifically stated or obvious from context, the term “or,” as used herein, is understood to be inclusive.

As used herein, the term “metal” refers to any chemical element that is a good tor of electricity and/or heat. Examples of metals include, but are not limited to, aluminum, cadmium, niobium (also known as “columbium”), copper, gold, iron, nickel, platinum, silver, tantalum, titanium, zinc, zirconium, and the like.

As used herein, the term “resin” refers to any synthetic or naturally occurring polymer.

Ranges provided herein are understood to be shorthand for all of the values within the range. For example, a range of 1 to 50 is understood to include any , combination of numbers, or sub—range from the group consisting 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, , 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 (as well as fractions thereof unless the context clearly dictates ise).

DETAILED DESCRIPTION OF THE INVENTION Corrugated Tubing Referring to a length of corrugated tubing 102 according to the prior art is provided. The corrugated tubing 102 may be composed of stainless steel or any other suitable material. The tubing 102 ns a number of corrugation peaks 104 and corrugation valleys 106. A jacket 108 (e.g., a multi—layer jacket) covers the outside of the tubing 102.

The jacket 108 can include a plurality of layers 110, 112. The layers 110, 112 generally form an annulus around the tubing 102, but may have a circular or non— ar cross—section.

Energy ative Tubing Referring now to in order to better absorb energy from fault currents and lightning s, energy dissipative jackets are ed that dissipate electrical and thermal energy throughout the respective s, thereby protecting the tubing 202. The term “dissipate” encompasses distributing electrical energy to an appropriate ing device such as a fitting.

Preferred embodiments of energy ative jackets preferably include one or more conductive layers for distributing electricity and heat. The conductive layers can include, for example, conductive resins and/or metals as discussed herein.

One embodiment of energy dissipative tubing 200 is depicted in The energy dissipative tubing 200 includes a length of tubing 202. The tubing 202 can be 2012/050103 metal tubing, thin—walled metal tubing, corrugated tubing, corrugated stainless steel tubing, or the like.

Tubing 202 is surrounded by a first resin layer 204, a metal layer 206, and a second resin layer 208. Resin layers 204, 208 can be formed from insulative and/or conductive .

Insulating resin layers can be formed from a variety of materials. In some embodiments, an insulating elastic layer includes polytetrafluoroethylene (PTFE).

Other suitable insulators include polyolefin compounds, thermoplastic polymers, thermoset rs, polymer nds, polyethylene, crosslinked polyethylene, UV—resistant polyethylene, ethylene—propylene rubber, silicone rubber, polyvinyl chloride (PVC), ethylene tetrafluoroethylene (ETFE), and ethylene propylene diene r (EPDM) rubber.

Conductive resin layers can be formed by impregnating a resin with conductive material such as metal particles (e.g., copper, aluminum, gold, silver, nickel, and the like), carbon black, carbon , or other conductive ves. In some embodiments, the metal layer 206 and/or one or more of the resin layers 204, 208 has a higher electrical conductivity than the tubing 202. In some embodiments, the volume resistivity of the conductive resin can be less than about 106 ohm—cm (e.g., 9 x 106 ohm—cm) as tested in accordance with ASTM standard D4496.

In some embodiments, each resin layer 204, 208 has a thickness of about 0.015" to about 0.035".

Metal layer 206 can include one or more metals (6. g., ductile metals) and alloys thereof. The metal(s) can be formed into foils, perforated foils, tapes, perforated tapes, cables, Wires, strands, , braids, and the like.

In some embodiments, the metal layer 206 is an expanded metal foil as further described in U.S. Patent Application Publication No. 2011—0041944. A variety of expanded metal foils are available from the Dexmet Corporation of Wallingford, Connecticut. An exemplary embodiment of energy dissipative tubing 200 with expanded metal foil is depicted in FIGS. 2.

In some embodiments, the metal layer 206 completely surrounds the first resin layer 24. In such embodiments, the metal may overlap and/or be welded or soldered in some s. In other embodiments, the metal layer 206 ntially nds the first resin layer 204. In such embodiments, a small portion of the first resin layer 204 (e.g., less than about 1°, less than about 2°, less than about 3°, less than about 4°, less than about 5°, less than about 10°, less than about 15°, less than about 20°, and the like) is not surrounded by the metal layer 26. In still other embodiments, the metal layer 206 can be wrapped spirally or helically around the first resin layer 204. In such an embodiment, the metal layer 26 can overlap or substantially surround the first resin layer 204 In some embodiments, the metal layer 206 is a conventional, non—expanded metal foil, such as aluminum or copper foil that can, in some embodiments, completely envelop the inner resin layer 206.

Various thicknesses of the resin layers 204, 208 and the metal layer 206 can be selected to achieve desired resistance to ing strikes and physical damage while maintaining desired levels of ility. In embodiments including an expanded metal foil, the mass per area can be ed to e an appropriate amount of energy dissipation. The resin layers 24, 28 can be the same or different thickness and can include the same or ent materials. Various colors or markings can be added to resin layers, for example, to clearly distinguish the resin layers 24, 28 from each other and from the metal layer 206 and/or to make the tubing 200 more conspicuous.

Sealing s Referring now to , an exploded view of a sealing device and tubing assembly 300 is provided. The assembly 300 allows for the sealing and coupling of an end of tubing 200 to a pipe, a manifold, an appliance, and the like (not depicted).

For example, after body member 304 is threaded onto a manifold (not depicted), tubing 200 and bushing 306 can be placed inside the sleeve portion 308 of the body member 304 and sealed by advancing a nut 310 as further discussed below.

Although the assembly 300 can be used with a variety of types of CSST, the bushing 306 is ularly advantageous when used with energy dissipative tubing 200 having one or more conductive layers.

As further illustrated in FIGS. 3B—3D, bushing 306 includes one or more axially—extending tongues 312a, 312b that can be placed in contact with the corrugated tubing 202 and/or one or more of the jacket layers 204, 206, 208. In the embodiment depicted in FIGS. 3B—3D, the axially—extending tongues 312 are placed between metal layer 206 (e.g. a metal foil layer) and an outer resin layer 208.

However, other configurations are le including placement of the tongues 312 between the tubing 202 and jacket layer 204, between jacket layer 204 and jacket layer 206, n jacket layer 206 and jacket layer 208, external to jacket layer 208, WO 52200 and the like. For example, when used in conjunction with single—jacketed tubing, the tongues 312 can be placed between the jacket layer 204 and the tubing 202 or external to the jacket 204 as depicted in . Likewise, when used in conjunction with unjacketed tubing, the tongues 312 can be placed external to the tubing 202 as depicted in .

By placing the tongues 312 in contact with one or more tive jacket layers (e.g., metal foil layer 206) and/or the tubing 202, the tongues 312 can form electrical continuity with one or more the conductive elements of the tubing 200, thereby effectively ing electrical charges applied to the tubing 200 while minimizing the risk of damage—causing flashover at the sealing device As most clearly seen in FIGS. 3C and 3D, axially—extending tongues 312 can, in some embodiments, be tapered to facilitate placement of the tongues under one or more jacket layers 204, 206, 208. For example, the taper angle between an inner wall and the outer wall of the tongues 312 can be n about 0" and about 5°, between about 0" and about 1", between about 1" and about 2", between about 2" and about 3°, between about 3" and about 4", between about 4" and about 5°, between about 1" and about 4", n about 2" and about 3°, and the like.

The y—extending tongues 312 can, in some ments, also have a tapered profile when viewed from perpendicular to the longitudinal axis of the tubing 200. A tongue 312 that substantially culminates in a point can enable easier insertion of the tongue 312 between multiple layers of the tubing 200. For example, the tongues 312 can have a substantially semi—circular or triangular profile when viewed from dicular to the longitudinal axis of the tubing 200 ted in dashed lines in FIGS. 3A—3C).

Bushing 306 can, in some embodiments, be a split g. For example, bushing 306 can include two halves 322a, 322b (each having a tongue 312a, 312b) connected by a living hinge. A living hinge allows the bushing to open to allow ribs 326a, 326b to slide over one or more corrugation peaks 104 before resting in a corrugation groove 106 and allowing the bushing 306 to return to a substantially circular profile for engagement with body member 304. In other embodiments, the bushing 306 is a two—piece split bushing such that each half of the split bushing is individually positioned on the tubing prior to insertion into the sleeve portion 308 of the body member 304.

In one ment, ribs 326 engage the first corrugation groove 106 of the tubing to facilitate the g of the tubing 200 against the body member 304. The ribs 326 can be located on a substantially opposite end of the bushing 306 from the tongues 312. As the nut 310 is advanced, the ribs 326 of the bushing 306 press the tubing 200 against the sealing face of the body member 304, causing the first corrugation peak 104 to collapse and form a gastight seal.

As most y e in , body member 304 can include a sealing face having one or more sealing circular ridges 328a, 328b configured to facilitate a metal—to—metal gastight seal. Such a g architecture is further described in U.S.

Patent Nos. 7,607,700 and 567 and embodied in the XR2 fitting available from Gastite of Portland, Tennessee.

Additionally, the axially—extending tongues 312 described herein can be adopted to a variety of other fitting architectures including, but not limited to, the architectures described in U.S. Patent Application Publication Nos. 2010—0181760 and 2010—0201124, as well as other CSST fittings produced by other manufacturers.

Referring still to FIGS. 3A—3D, nut 310 can have external s 330 configured to mate with internal threads 332 in the sleeve portion 308 of body member 304. As the nut 310 is d, the s 330, 332 cause the nut 310 to advance towards the body member 304. The nut 310 engages with the tubing 200, the bushing 306, and/or the tongues 312 to drive the tubing 200 forward to crush a corrugation peak 104 to form the seal ed in FIGS. 3C and 3D.

Nut 310 can have an internal taper complimentary to the external taper of tongues 312. This complimentary taper can advantageously press the tongues 312 against a conductive layer, press a tive layer against the tongues, and/or compress one or more layers of the jacket between the tongues 312 and nut 310 to retain the jacket within the sealing device.

In some embodiments, one or more components of the sealing device are fabricated from a conductive material such metals or metal alloys. For example, the bushing 306 and the body member 304 can be conductive to facilitate the efficient flow of electricity from the tubing 200 to the bushing 306 to the body member 304 and eventually to ground via whatever device is connected to the body member 304.

As will be appreciated by one of ordinary skill in the art, the s components of the sealing device can be fabricated by various techniques including casting, stamping, machining, molding, and the like.

Torque—Limiting Nut Referring now to another embodiment of the invention utilizes a nut 400 having a torque—limiting e. The torque—limiting feature reduces the likelihood of an installer over—tightening or under—tightening a fitting by ing positive feedback to the installer when an appropriate amount of torque is applied to the nut 400.

One embodiment of such a nut 400 includes two hexagonal regions 402 and 404 separated by a notched shear point 406 having a reduced diameter (D3). In some embodiments, the distal hexagonal region 404 has a longer length (Ld) than the length (LP) of the proximal hexagonal region 402 to promote the ation of torque solely to the distal hexagonal region 404 during installation.

During installation, a wrench, pliers, or other tool is applied to the distal hexagonal region 404 to advance the nut 400 to form a seal as described . Once the seal is formed and predetermined amount of torque (e.g., about 50 foot—pounds) is applied to the distal hexagonal region 404, the distal hexagonal portion 404 shears from the remainder of the nut 400 at the shear point 406. In some embodiments, the proximal hexagonal n 404 remains to allow removal of the nut. In other embodiments, a shear point is positioned between the threaded portion of the nut and the hexagonal n to preclude l of the nut 400 for safety purposes.

The amount of permissible torque can be determined by one of ordinary skill in the art by design and/or testing and may vary to reflect various designs, materials, and dimensions of the tubing 200 and sealing device. In general, a deeper notch at shear point 406 will result in the ation of less torque before shearing.

Although the nuts 310, 400 are depicted and described herein as nal, one of ordinary skill in the art will readily iate that other geometries can be utilized including square, octagonal, and the like.

Methods of Installing Tubing Tubing can be installed in accordance with existing techniques for the manufacture of CSST. An exemplary method 500 for installing energy dissipative tubing is depicted in In step $502, a length of tubing is provided. Tubing can, in some embodiments, be CSST such as unjacketed CSST, jacketed CSST, and energy— dissipative tubing. Tubing may be provided in s (e.g., 8’ sticks) or on reels.

In step $504, one or more jacket layers are optionally removed in accordance with the instructions for a fitting. The one or more layers can be removed with existing tools such as a utility knife, a razor blade, a tubing cutter, and the like.

In step $506, a sealing device is provided including a body member defining a sleeve n and a bushing including one or more tongues adapted and configured to be received over at least an inner tubing layer of the length of tubing.

In step $508, the sealing device is optionally coupled to another device. For example, the sealing device can be coupled to a source of a fuel gas such as a pipe, a manifold, a meter, a gas main, a tank, and the like. In another example, the sealing device can be coupled to an appliance that es a fuel gas such as a stove, an oven, a grill, a e, a clothes dryer, a fire place, a tor, and the like. The sealing device can be coupled to the other device by threaded or other attachments. In some circumstances, pipe seal tape (e.g., polytetrafluoroethylene tape) or pipe seal compound (commonly referred to as “pipe dope”) is utilized to facilitate a gastight seal between the sealing device and the other device.

In step $510, the bushing is placed over the inner tubing layer. The bushing can be positioned such that one or more s are located n one or more layers of the tubing. For example, the g can be positioned such that the one or more s are located in contact with a conductive layer of the tubing.

In step $512, a nut is advanced to form a seal. The nut can be advanced by rotating the nut to engage threads in the sleeve portion of the body member.

In step $514, the nut is optionally tightened until a torque—limiting portion of the nut is activated. For example, a portion of the nut may shear off when a predetermined amount of torque is applied to the nut.

INCORPORATION BY REFERENCE The entire contents of all patents, published patent applications, and other references cited herein are hereby expressly incorporated herein in their entireties by reference.

Claims (24)

1. A bushing comprising: one or more substantially circumferential ribs adap ted to engage one or more corrugations of a tube; one or more y-extending tongues located on a substantially te end of the bushing from the one or more ntially circ umferential ribs, wherein the one or more axially-extending tongues are tapered towar d an end of the bushing; wherein the bushing is fabricated from a conductive material; and wherein the one or more y-extending tongues a re adapted and configured to form electrical continuity with the tube.

2. The bushing of claim 1, wherein the bushing is a split bushing.

3. The bushing of claim 1, wherein the bushing is a two-piece bushing.

4. The bushing of claim 1, wherein the bushing includes two halves coupled by a living hinge.

5. The bushing of claim 1, n the bushing includes at least two axiallyextending tongues.

6. The bushing of claim 1, wherein the one or more axially-extending tongues have a substantially semi-circular profile.

7. The bushing of claim 1, wherein the one or more axially-extending tongues have a taper angle of between about 1º and about 4º.

8. The bushing of claim 1, wherein the tube es one or more conductive jacket layers and the one or more axially-extending tongues are adapted to form electrical continuity with at least one of the one or more tive jacket layers.

9 A sealing device for ting a length of tubing, the sealing device comprising: a body member defining a sleeve portion; and the bushing of claim 1 adapted and configured to be received in the sleeve portion, wherein the one or more axially-extending tongues are adapted and configured to be received over at least one layer of the .

10. The g device of claim 9, further comprising: a nut adapted and configured for threaded coupling with the body member.

11. The sealing device of claim 10, wherein the g and the nut are dimensioned such that as the nut is tightened, the one or more axially-extending tongues are compressed against the tubing by the nut.

12. The sealing device of claim 10, wherein the tubing includes a jacket.

13. The sealing device of claim 12, wherein the bushing and the nut are dimensioned such that as the nut is tightened, one or more layers of the jacket are compressed between an interior surface of the nut and an exterior surface of the one or more axially-extending tongues.

14. The sealing device of claim 12, wherein the bushing and the nut are dimensioned such that as the nut is tightened, the one or more axially-extending tongues are compressed t one or more layers of the jacket by the nut.

15. The sealing device of claim 10, wherein the nut has an al thread and the sleeve portion of the body member has a complimentary internal thread.

16. The sealing device of claim 10, wherein the nut has a tapered inner surface.

17. The sealing device of claim 10, wherein the nut includes a -limiting feature.

18. A length of tubing comprising: an inner tubing layer; and a fitting coupled to an end of the , the fitting including: a body member defining a sleeve portion; and the bushing of claim 1 extending partially over at least the inner tubing layer and received along with at least the inner tubing layer in the sleeve n, wherein the one or more axially-extending tongues are adapted and configured to be received over the inner tubing layer.

19. The length of tubing of claim 18, further comprising: a conductive layer surrounding the outside of the inner tubing layer, wherein the one or more axially-extending tongues are in contact with the conductive layer.

20. The length of tubing of claim 19, wherein the one or more axially-extending tongues are positioned between the inner tubing layer and the conductive layer.

21. The length of tubing of claim 19, further comprising: an outer tubing layer surrounding the outside of the conductive layer, wherein the one or more y-extending tongues are positioned between the tive layer and the outer tubing layer.

22. A method of installing energy dissipative tubing, the method comprising: providing a length of tubing including: an inner tubing layer; providing a sealing device ing a body member defining a sleeve portion and the bushing of claim 1; placing the g over at least the inner tubing layer such that the one or more axially-extending tongues are positioned over the inner tubing layer; and inserting the bushing and at least the inner tubing layer into the sleeve portion.

23. A length of tubing comprising: an inner tubing layer; a tive layer surrounding the outside of the i nner tubing layer; an outer tubing layer surrounding the outside of th e conductive layer; and a fitting coupled to an end of the tubing, the g including: a body member defining a sleeve portion; and the bushing of claim 1 extending partially over at least the inner tubing layer and received along with at least the inner tu bing layer in the sleeve portion, wherein the one or more axially-extending tongues are positioned between the conductive layer and the outer tubing layer.

24. A bushing substantially as herein described with reference to any one of the embodiments rated in