Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
  • H02G15/00—Cable fittings
  • H02G15/013—Sealing means for cable inlets
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C33/00—Moulds or cores; Details thereof or accessories therefor
  • B29C33/0011—Moulds or cores; Details thereof or accessories therefor thin-walled moulds
  • B29C33/0016—Lost moulds, e.g. staying on the moulded object
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C33/00—Moulds or cores; Details thereof or accessories therefor
  • B29C33/0033—Moulds or cores; Details thereof or accessories therefor constructed for making articles provided with holes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C39/00—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor
  • B29C39/003—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor characterised by the choice of material
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
  • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
  • H01R4/70—Insulation of connections

Definitions

• the invention relates to a packaged gel article.
• the invention further relates to the method of making a packaged gel article.
• an electrical cable is divided into two or more components, for example, where a branch-off cable is connected to a main cable or where a cable containing two or more cores, is separated into the individual cores.
• the cable insulation generally has been removed to permit the jointing of a branch-off cable or breakout of the cable cores. The area where the insulation has been removed must then be reinsulated.
• the shielding and armoring is also removed and must be re-established. This is generally accomplished by installing an enclosure around that region of the cables.
• breakout is used in this application to refer to either two or more cables or two or more cores where they separate from a main cable or cables.
• Enclosures suitable for this use can be, for example, resin filled joint cases, polymeric sleeves or the like.
• a number of methods have been used to seal breakouts with varying success.
• a heat shrinkable polymeric boot may be positioned on the breakout using mastic or adhe ⁇ sive to hold the boot in place. Heat shrinkable boots however are costly to manufacture because of their shape and usually require access to the cable conductor ends to slip the boot into the proper position over the breakout area.
• Adhesives and mastics have been put in the area between the breakout cable core and the main cable (crotch area) to seal but these are difficult to pack into the crotch area without leaving voids resulting in a poor seal and may require heat to cause them to flow and fill the crotch area.
• the appli ⁇ cation of heat can damage the conductor covering or the con ⁇ ductor.
• Tapes of dimensionally stable polymeric material with an adhesive or mastic have been used to wrap the cable breakout area but tend to leak if not properly overlapped.
• Shaped articles have been used as sealing elements in a variety of methods.
• Tn US 4,438,294 a sealing element of a thermoplastic or plastic material for a cable entrance socket is disclosed.
• the sealing element seals the area between the sheaths of cables using straight sided or con ⁇ cave articles which surround only a portion of the cable and conductors in the crotch area.
• No gels are disclosed and the thermoplastic or plastic materials described are substantially non-tacky and rigid.
• polymeric article comprising a cylindrical member with a plura ⁇ lity of channels for enclosing a plurality of cables.
• the articles may seal by being made heat recoverable or may be sealed with an adhesive or mastic. They are non-tacky, and useful to seal, protect and insulate cables. No gels are described.
• a branch off seal is disclosed comprising a heat recoverable sleeve and one or more clips attached to the sleeve opening to form the sleeve into a desired number of cable conduits.
• a variety of molds for casting shaped articles are well known. Reusable molds made of metal, polymers, glass and ceramics are used in casting a wide variety of polymeric shapes and articles. Reusable molds are generally expensive to make and require that the article formed therein be packaged and handled separately. Disposable molds come in a variety of materials, for example wax.
• the invention relates to a packaged gel article and a method of manufacturing a packaged gel article.
• the packaged gel article comprises a mold and a shaped article:
• said mold comprising a hollow cylindrical con ⁇ figuration having a circumference substantially corresponding to the shaped article which is in the mold;
• said.,mold having therein a shaped article comprising a polymeric gel.
• the gel having a cone penetration value of about 30 to about 400 (lO -1 mm) and an elonga ⁇ tion of from about 25% to about 850%
• said mold and mandrels being made of a relatively rigid material having a flexural modulus of at least about 4x10-3 psi that is substantially incompatible with the shaped article, is dimensionally stable at the tem ⁇ perature the gel was formed at and has a release rate from the gel composition of at least 0.02 in/sec on 180° peeling.
• the invention also relates to a method of manufacturing a shaped article having one or more holes extending at least partially therethrough and a mold, which method comprises:
• said mold and mandrels being made of a relatively rigid material having a flexural modulus of at least about 3 4x10 psi that is substantially incompatible with the shaped article, is dimensionally stable at the gel forming tem ⁇ perature and has a release rate from the gel composition of at least 0.02 in/sec on 180° peeling to obtain a shaped article having one or more holes extending at least par ⁇ tially therethrough, the number of holes corresponding to the number of mandrels used in step ( ⁇ ).
• the mold of the invention is made of a relatively rigid material having a flexural modulus of at least about
• the mold While other orga ⁇ nic or inorganic materials may be suitable for the mold e.g. certain metals or alloys, it is preferred in the invention that the mold be made of a polymeric material.
• Preferred polymers include polycarbonates, polyethylene, polypropy ⁇ lene, polystyrene, ABS, polyester, polyamides, fluoropoly- mers and silicone surface treated plastics. Especially preferred are polycarbonates.
• the mold material must be dimensionally stable at the gel forming temperature i.e. must have a melting point or glass transition temperature higher than the highest tem ⁇ perature that the liquid composition capable of forming a gel attains during the making of the shaped article in the mold. It can also be supported during gel formation e.g. an exterior support in order to maintain the dimensional stability.
• relatively rigid is meant that the mold material has a flexural modulus of at least about 4x10 3 psi and pre-
• the mold material must release from the gel relatively easily during installation of the shaped article e.g. on a cable breakout. If the release rate is too low the shaped article may tear or stretch out of shape and thus be unu ⁇ sable. It has been found that a lower degree of releasabi- lity is preferred. Since the shaped article is to be stored in the mold, it is preferred that the shaped article stick in the mold enough to keep from falling out due to general gravitational or other minor pulling forces. In general the release rate should be at least 0.02 in/sec. for a one- eight inch thickness of polymeric gel on a 6 inch 1 inch strip of mold material to which a 1 lb. weight has been attached such that the pulling force is at an angle of 180° to the mold material. The releaseability can be achieved either by the material chosen for the mold itself or by coating or lining the interior of the mold to control release.
• the mold material be notch sensitive.
• notch sensitivity is meant that the material will readily break under normal manual pressure once the material has been notched or scored to facilitate removal of the mold material.
• Notch sensitivity is measured by ASTM D-256. Notch sensitivity is desirable to aid in the removal of the mold or part of the mold from the shaped article. After scoring the mold, pressure applied to the area around the score by squeezing or the like will cause the mold material to break along the score. The edge formed at the break can be grasped to pull the mold away from the shaped article.
• a portion of the mold material can be left on the shaped article upon installation.
• the remaining mold portion may act as a cover or other protective means for any exposed portions of the shaped article.
• the mold may be formed by any convenient means based on the material chosen for the mold. So for example, where polymers are chosen the mold may be made by extrusion, or thermoforming such as blow or injection molding.
• the mandrels are chosen with the same requirements as the mold material.
• the mandrels are designed preferably cylindri ⁇ ally such that when inserted into the mold the mandrels will cause holes to be formed at least away through the shaped article.
• the number of mandrels should correspond to the number of holes desired in the shaped article.
• the mandrel may also be an integral part of the mold.
• the hole may be formed on the edge of the article ( Figure 6) by such integral mandrel.
• the shaped article preferably has a number of holes, corresponding to the number of cables or cores of the breakout.
• the holes are formed preferably slightly smaller than the size of the cable that is to be inserted therein.
• the gels used in the invention will stretch to accommodate the increased size cable and the tension created provides a better seal.
• the number of holes should correspond to the number of cables to pass therethrough.
• the holes may be stretched by placing tubes, mandrels or other articles in the holes to keep them in an expanded condition prior to placing the shaped article around the cables.
• the tubes mandrels or other articles may be an integral part of the mold itself or they may be interested later prior to placing the shaped article around the cable. The tubes may then be removed when the shaped article is in place.
• a hole may also be larger or the same size as the cable.
• the slit may be formed by using one or more tubes end insertion with an additional piece of material target to the edge of tube which runs to the edge of the mold which forms an integral pact of the mold of the inven ⁇ tion. (See e.g. Figure 1 and 2).
• the polymeric gel is selected such that it has a cone penetration value as measured by ASTM D-937-77, of from about 30 to about 400 (10 ⁇ mm) and preferably from about 50 to about 350 (10 ⁇ 1 mm). Further, said gel is selected such that it has an elongation, as measured by ASTM D-412, of from about 25% to about 850% and more preferably from about 100% to 750%.
• the gels may further be selected for their insulation, stress grading, or conductive properties as well as sealing. Generally,- it is preferable that the gel should have a dielectric constant (permittivity) of less than 6 at 50 Hz for insulating gels and greater than 6 for stress grading gels (as measured by ASTM D-150).
• the gels pre ⁇ ferably have a volume resistivity of at least 10 ⁇ ohm-cm (as measured by ASTM D-257).
• the gels preferably have a specific impedance of 10 ⁇ -10-1° ohm-cm at 50 Hz (ASTM D-150), and for conductive applications, the gels preferably have a volume resistivity of less than 10 ⁇ ohm-cm.
• the gel posses sufficient tack to seal and adhere to the breakout or a cable end. Further the properties of the gel allow cable movement without breaking the seal formed, due to the gels ability to deform and return to its substantially original shape while maintaining the tack necessary to seal.
• Preferred gels for use in this invention are gelloid compositions comprising a crosslinked non-silicone polymer having an olefinic unsaturated content of less than 10 mole percent and having dispersed therein a liquid in an amount of from about 20% to about 95% by weight based on the weight of the liquid and polymer and from 0 to 0.3 volume fraction of a filler, said cross-linked polymer
• composition having a storage modulus of (l+2.5v+14.lv ⁇ ) ⁇ dynes/cm ⁇ wherein x is less than 5x10 ⁇ at 30°C and greater than 5xl0 2 at 90°C, and v is the volume fraction of the filler, with the proviso that, if the crosslinked polymer is prepared from a solid high molecular weight polymer, the storage modulus at 140°C is at least about 70% of the storage modulus at 70°C, and a dynamic viscosity of (l+2.5v+14.1v2)y poises wherein y is less than IxlO 5 at 30°C and greater than 5xl0 2 at 90°C and v is the volume fraction of the filler, said composition exhibiting first degree blocking.
• compositions are preferably preoared by subjecting a non-silicone liquid polymer containing from about 20% to about 95% by weight of a liquid to a ⁇ rosslinking means such as a chemical means or irradiation means.
• the polymer starting material is a crosslinkable liquid polymeric material, preferably a non-silicone liquid rubber, with low or no unsaturation prior to crosslinking.
• the liquid poly ⁇ meric material preferably has a molecular weight of less than about 90,000, preferably less than about 50,000, and a Mooney viscosity of ML 1+4 at 100°C of less than 10. Mooney viscosity is measured by ASTM D-1646.
• Said polymers are primarily .liquids at these molecular weights and viscosi ⁇ ties.
• the liquid polymer preferably has a molecular weight less than about 7.5 times the polymer's critical molecular weight (see e.g. Mechanical prop of Polymers, Nielsen 1962 for a discussion of critical molecular weight).
• the poly ⁇ mers can be a hydrocarbon backbone polymer or a polymer con ⁇ taining carbon as well as other atoms, e.g. oxygen, nitrogen, etc. in the backbone with the exception of sili- cone. The polymers are limited to those which have low or no unsaturation prior to ⁇ rosslinking.
• the amount of unsaturation will be less than about 10% mole, preferably less than about 7 mole percent and preferably less than 4 mole percent. If the unsaturation is too high the resulting product tends to be thermally unstable.
• Preferred liquid polymeric materials include liquid butyl rubber, epichlorohydrin rubber, ethylene-propylene- diene monomer rubber (EPDM), hydrogenated polyisoprene, hydrogenated polybutadiene, hydrogenated styrene-butadiene rubber (SBR), hydrogenated polychloroprene, functionalized polyisobutylene (i.e.
• polyisobutylene with reactive groups added that are capable of crosslinking such as hydroxy, amine or ⁇ arboxy groups
• chlorinated polyethylene such as hydroxy, amine or ⁇ arboxy groups
• liquid fluorinated polymers e.g. Viton from DuPont
• the liquid dispersed in the crosslinked polymer in accordance with this invention can be any liquid which is capable of being dispersed in the polymer in an amount from about 20% to about 95%, and which does not react during crosslinking of the polymer.
• the liquid may be a plasti- cizer, compatibilizer, tackifier, or the like.
• Suitable liquids include, for example, paraffini ⁇ oils, naphthenate oils, aromatic oils, liquid polybutenes, alkyl (or aryl) phthalates, vegetable oils, mineral oils, trimellitates, esters of polyethylene glycols, alkyl (or aryl) phosphates, methyl ester of hydrogenated wood rosin, liquid rosin oils, pine tar, polyterpenes, non-reacting liquid rubbers, the starting liquid polymer which remains uncrosslinked or at least crosslinked less than .1 crosslink per weight average molecule, and the like.
• Crosslinking may be by any conventional crosslinking means, preferably ⁇ V means, irradiation means or by chemical means. Radiation crosslinking can be accomplished by electron beam, or the like treatment. Suitable ⁇ rosslinking promoters can be incorporated to encourage radiation crosslinking such as triallyl ⁇ yanuate and triallyliso- ⁇ yanuate. Suitable ⁇ hemi ⁇ al ⁇ rosslinking agents ⁇ an be ⁇ ho- sen based on the individual polymer or polymers used.
• a phenoli ⁇ resin or p-quinone dioxime ⁇ an be used to ⁇ ure butyl rubber
• peroxide can be used to cure EPDM or diisocyanate dimer a ⁇ id ⁇ an be used to ⁇ ure epi ⁇ hlorohydrin rubber.
• plasti ⁇ izers may be added to help obtain a gelloid with the desired ⁇ one penetration values.
• Su ⁇ h plasti ⁇ izers preferably would include all liquids which are capable of reducing the viscosity of the base rubber, have low or no unsaturation as described above and are ⁇ ompatible with the base rubber.
• a filler may be added to the ⁇ omposition, if desired.
• the amount of filler added is from 0 to 0.3 volume fra ⁇ tion.
• the filler is in an amount from .1 to 0.2 volume fra ⁇ tion.
• the term "filler” is used herein to in ⁇ lude all solid additives in ⁇ luding parti ⁇ ulate matter or fibrous matter present in the ⁇ omposition. These fillers in ⁇ lude pigments, fillers known for ⁇ ondu ⁇ t-ive, (both ele ⁇ tri ⁇ al and thermal) stress grading and insulative purposes e.g.
• compositions are formed preferably by mixing a liquid non-silicone polymer with any desired fillers in an amount of from 0 to 0.3 volume fraction, any crosslinking agents or the like and the liquid and subjecting the mixture to a ⁇ rosslinking means.
• the ⁇ omposition will generally take the shape of the ⁇ ontainer during ⁇ rosslinking but ⁇ an be reshaped e.g. by cutting as desired.
• the term cable is used in this appli ⁇ ation to refer to one or more ele ⁇ tri ⁇ al ⁇ ondu ⁇ tors surrounded by electrical insulation.
• two or more ⁇ ores i.e. ⁇ ondu ⁇ tor and insulation, are divided from a main ⁇ able whi ⁇ h ⁇ ontains those ⁇ ores surrounded by a ⁇ ommon insulation layer, optionally with shielding and/or armoring.
• a sealing method is applied to seal between the individual ⁇ ores and the individual ⁇ ores and en ⁇ losure.
• the term ⁇ able in the general des ⁇ ription and claims is to be understood to cover the individual cores of a breakout or the main cable or the like.
• two or more ⁇ ables are jointed to a main ⁇ able.
• breakout is used herein to apply to su ⁇ h bran ⁇ h-offs as well as breakouts.
• the shaped arti ⁇ le and/or the mold or mandrels of the invention ⁇ an ⁇ ontain various additives as desired.
• Additives in ⁇ lude, for example, stabilizers, reinfor ⁇ ing or non-reinfor ⁇ ing fillers, pigments, ⁇ arbon bla ⁇ k, plasti ⁇ i ⁇ zers, surfa ⁇ tants, pro ⁇ essing aids, ⁇ orrosion inhibitors, ⁇ ondu ⁇ tive fillers, fungi ⁇ ides, bio ⁇ ides, leak indi ⁇ ators, and the like.
• a pa ⁇ kaged gel arti ⁇ le is formed by assembling a mold ⁇ omprising a material as previously des ⁇ ribed.
• the mold has additional mandrels or other inserts or means for forming holes partly or wholly through the shaped arti ⁇ le.
• the mold is provided with a means for introdu ⁇ ing a slit between the hole and the edge of the shaped arti ⁇ le.
• a preferred means for forming slit ⁇ omprises a polymeri ⁇ sheet pla ⁇ ed between the hole forming means and the. edge of the mold.
• the mold is ⁇ losed after the liquid ⁇ omposition ⁇ apable of forming a gel is pla ⁇ ed therein and the mold is held together by any ⁇ onvenient means su ⁇ h as adhesives, masti ⁇ s, ⁇ lamps, or the mold is held together by .the ta ⁇ k of the gel holding the molds parts in pla ⁇ e or by the ⁇ lose toleran ⁇ e and fri ⁇ tion of the parts of the mold.
• the liquid ⁇ om ⁇ position is then set by ⁇ uring, ⁇ rosslinking or the like as appropriate for the ⁇ hosen gel.
• the pa ⁇ kaged gel arti ⁇ le is then suitable for storage of the shaped arti ⁇ le and further ⁇ more is useful for handling the shaped arti ⁇ le during installation an a - ⁇ able breakout, ⁇ able end or the like without the handling diffi ⁇ ulties asso ⁇ iated with ta ⁇ ky materials.
• a portion of the mold may be broken away to give a ⁇ ess to a large enough portion of the gel to make the installation.
• the installer will handle the gel by a por- tion of the mold remaining around the gel after removal of a portion of the mold to give a ⁇ ess to the area to be installed. After installation the remaining mold may be removed or may remain to act as a mechani ⁇ al prote ⁇ tion ⁇ over or ⁇ over for the shaped arti ⁇ le that is exposed to the environment.
• Figure 1 is a disposable mold that forms a ⁇ ontainer that a shaped arti ⁇ le of p ⁇ lymeri ⁇ gel ⁇ an be stored in.
• Figure 2 is an exposed view of Figure 1 wherein 1 is the top portion whi ⁇ h is left off while the un ⁇ ured polymeri ⁇ gel is added to the mold and then put on to ⁇ ure and store the gel.
• the hole forming means 2 is a tubular insert whi ⁇ h when pla ⁇ ed in the mold fits in holders 3 and 4 in the top 1 and bottom 5 portions also the hole forming means has an additional pie ⁇ e 6 for forming a slit in the shaped arti ⁇ le.
• the body 7 of the mold is an oval pie ⁇ e form from a sheet of disposable material.
• FIG. 1 and bottom 5 As well as any hole or slit forming means 2, 6 may be removed for installa ⁇ tion.
• the installation would handle the shaped arti ⁇ le by holding mold body 7 until the shaped arti ⁇ le is in pla ⁇ e and then removing the mold body.
• Figures 3 and 4 show shaped arti ⁇ le 8 and 11 of a polymeri ⁇ gel, formed from a mold used in the invention.
• the articles each have holes 9 for posi ⁇ tioning ⁇ ables therethrough and slits 10 for positioning the shaped arti ⁇ le around ⁇ ables without a ⁇ ess to the free end of the ⁇ able.
• Figure 5 shows a shaped arti ⁇ le 12 with a hole 13 a portion of the way for positioning a ⁇ able end therein.
• Figure 6 shows a shaped arti ⁇ le having holes wherein the edges are open formed by mandrels whi ⁇ h are an integral part of the mold.
• a mold is made a ⁇ ording to Figure 1 of a poly ⁇ arbonate material having a flexural modulus of 3.4x10 ⁇ by inje ⁇ tion molding.
• An un ⁇ ured liquid butyl rubber is pla ⁇ ed inside and the liquid butyl rubber is ⁇ rosslinked to form a gel.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Liquid Crystal (AREA)
• Sealing Battery Cases Or Jackets (AREA)
• Secondary Cells (AREA)

Applications Claiming Priority (2)

Publications (2)

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• 1986
  • 1986-05-02 EP EP19860903754 patent/EP0225370A4/fr not_active Withdrawn
  • 1986-05-02 WO PCT/US1986/000967 patent/WO1986006316A1/fr not_active Application Discontinuation
  • 1986-05-02 JP JP50304886A patent/JPS62502743A/ja active Pending
  • 1986-05-02 AU AU59515/86A patent/AU5951586A/en not_active Abandoned

Patent Citations (2)

Non-Patent Citations (1)

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