Abstract

A method of installing a fire resistant corrugated coaxial cable that employs a high-temperature, insulating alkaline earth silicate (AES) wool dielectric is described. The AES wool dielectric is devoid of water as a constituent. The AES wool may be survivable under conditions of high heat, such as temperatures specified by common fire test standards (e.g., 1850° F./1010° C. for two hours). The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. A layer of ceramifiable silicone rubber or refractory fiber wrap can surround the outer conductor and continues to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket burns away.

IPC Classes  ?

• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor
• H01B 3/08 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances quartzInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances glassInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances glass woolInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances slag woolInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances vitreous enamels
• H01B 3/12 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances ceramics
• H01B 3/46 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances plasticsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances resinsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances waxes silicones

Abstract

A method of installing a fire resistant coaxial cable is described in which the cable has a 2-part dielectric made of a polymer foam and a ceramifiable silicone rubber. The polymer foam, which can be polypropylene or other polymers, leaves little-to-no residue in the cable that causes electromagnetic loss when upon burning. The polymer foam can be extruded over a center conductor using an inert gas, such as nitrogen, to propagate the foam, ensuring little-to-no residue in the cable. The ceramifiable silicone rubber can be extruded over the polymer foam. The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. Another layer of ceramifiable silicone rubber can surround the outer conductor and continue to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket outer layer burns away.

IPC Classes  ?

• H01B 13/26 - SheathingArmouringScreeningApplying other protective layers by winding, braiding or longitudinal lapping
• H01B 7/18 - Protection against damage caused by external factors, e.g. sheaths or armouring by wear, mechanical force or pressure
• H01B 7/295 - Protection against damage caused by external factors, e.g. sheaths or armouring by extremes of temperature or by flame using material resistant to flame
• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor
• H01B 13/016 - Apparatus or processes specially adapted for manufacturing conductors or cables for manufacturing co-axial cables

Abstract

A fire resistant corrugated coaxial cable is described that employs a high-temperature, insulating alkaline earth silicate (AES) wool dielectric. The AES wool dielectric is devoid of water as a constituent. The AES wool may be survivable under conditions of high heat, such as temperatures specified by common fire test standards (e.g., 1850° F./1010° C. for two hours). The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. A layer of ceramifiable silicone rubber or refractory fiber wrap can surround the outer conductor and continues to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket burns away.

IPC Classes  ?

• H01B 3/08 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances quartzInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances glassInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances glass woolInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances slag woolInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances vitreous enamels
• H01B 3/12 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances ceramics
• H01B 3/46 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances plasticsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances resinsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances waxes silicones
• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor

Abstract

A fire resistant coaxial cable and method of making is described that has a 2-part dielectric made of a polymer foam and a ceramifiable silicone rubber. The polymer foam, which can be polypropylene or other polymers, leaves little-to-no residue in the cable that causes electromagnetic loss when upon burning. The polymer foam can be extruded over a center conductor using an inert gas, such as nitrogen, to propagate the foam, ensuring little-to-no residue in the cable. The ceramifiable silicone rubber can be extruded over the polymer foam. The ceramifiable silicone rubber can have a polysiloxane matrix with inorganic flux and refractory particles that ceramify under high heat, such as temperatures specified by common fire test standards (e.g., 1850° F./1010° C. for two hours). The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. Another layer of ceramifiable silicone rubber surrounds the outer conductor and continues to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket burns away.

IPC Classes  ?

• H01B 13/26 - SheathingArmouringScreeningApplying other protective layers by winding, braiding or longitudinal lapping
• H01B 7/18 - Protection against damage caused by external factors, e.g. sheaths or armouring by wear, mechanical force or pressure
• H01B 7/295 - Protection against damage caused by external factors, e.g. sheaths or armouring by extremes of temperature or by flame using material resistant to flame
• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor
• H01B 13/016 - Apparatus or processes specially adapted for manufacturing conductors or cables for manufacturing co-axial cables
• H01B 3/46 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances plasticsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances resinsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances waxes silicones
• H01B 3/28 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances natural or synthetic rubbers

Abstract

A fire resistant coaxial cable and method of making includes a 2-part dielectric made of a polymer foam and a ceramifiable silicone rubber. The polymer foam, which can be polypropylene or other polymers, leaves little-to-no residue in the cable that causes electromagnetic loss when upon burning. The polymer foam can be extruded over a center conductor using an inert gas, such as nitrogen, to propagate the foam, ensuring little-to-no residue in the cable. The ceramifiable silicone rubber can be extruded over the polymer foam. The ceramifiable silicone rubber can have a polysiloxane matrix with inorganic flux and refractory particles that ceramify under high heat, such as temperatures specified by common fire test standards (e.g., 1850° F./1010° C. for two hours). The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. Another layer of ceramifiable silicone rubber surrounds the outer conductor and continues to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket burns away.

IPC Classes  ?

• H01B 7/02 - Disposition of insulation
• H01B 7/295 - Protection against damage caused by external factors, e.g. sheaths or armouring by extremes of temperature or by flame using material resistant to flame
• H01B 3/46 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances plasticsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances resinsInsulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances waxes silicones
• H01B 7/18 - Protection against damage caused by external factors, e.g. sheaths or armouring by wear, mechanical force or pressure
• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor
• H01B 3/28 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of organic substances natural or synthetic rubbers

Abstract

Methods of testing and installing fire-resistant coaxial cables are described. The dielectric between the coax cable's central conductor and outer coaxial conductor ceramify under high heat, such as those specified by common fire test standards (e.g., 1850° F./1010° C. for two hours). The dielectric can be composed of ceramifiable silicone rubber, such as that having a polysiloxane matrix with inorganic flux and refractory particles. Because thick layers of uncured ceramifiable silicone rubber deform under their own weight when curing, multiple thinner layers are coated and serially cured in order to build up the required thickness. A sacrificial sheath mold is used to hold each layer of uncured ceramifiable silicone rubber in place around the central conductor while curing. The outer conductor can be a metal foil, metal braid, and/or corrugated metal. Another layer of extruded ceramifiable silicone dielectric or an outer wrap of ceramic fiber yarn surrounds the outer conductor and continues to insulate it from the outside if a low smoke zero halogen jacket burns away.

IPC Classes  ?

• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor
• H01B 7/295 - Protection against damage caused by external factors, e.g. sheaths or armouring by extremes of temperature or by flame using material resistant to flame

Abstract

Fire-resistant coaxial cables are described as well as methods to manufacture them. The dielectric between the coax cable's central conductor and outer coaxial conductor ceramify under high heat, such as those specified by common fire test standards (e.g., 1850° F./1010° C. for two hours). The dielectric can be composed of ceramifiable silicone rubber, such as that having a polysiloxane matrix with inorganic flux and refractory particles. Because thick layers of uncured ceramifiable silicone rubber deform under their own weight when curing, multiple thinner layers are coated and serially cured in order to build up the required thickness. A sacrificial sheath mold is used to hold each layer of uncured ceramifiable silicone rubber in place around the central conductor while curing. The outer conductor can be a metal foil, metal braid, and/or corrugated metal. Another layer of extruded ceramifiable silicone dielectric or an outer wrap of ceramic fiber yarn surrounds the outer conductor and continues to insulate it from the outside if a low smoke zero halogen jacket burns away. Methods of testing and installation are described.

IPC Classes  ?

• H01B 7/00 - Insulated conductors or cables characterised by their form
• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor
• H01B 7/295 - Protection against damage caused by external factors, e.g. sheaths or armouring by extremes of temperature or by flame using material resistant to flame

Abstract

A fire-resistant coaxial cable is described in which the dielectric between the central conductor and outer coaxial conductor can ceramify under high heat. The dielectric is composed of a ceramifiable silicone rubber, such as that having a polysiloxane matrix with inorganic flux and refractory particles. An outer wrap of ceramic fiber yarn surrounds the outer conductor and continues to insulate it from the outside if a low smoke zero halogen jacket burns away. Embodiments include those with durable corrugated outer conductors or flexible braided outer conductors. Methods of testing and installation are described.

IPC Classes  ?

• H01B 7/295 - Protection against damage caused by external factors, e.g. sheaths or armouring by extremes of temperature or by flame using material resistant to flame
• H01B 7/20 - Metal tubes, e.g. lead sheaths
• H01B 11/18 - Coaxial cablesAnalogous cables having more than one inner conductor within a common outer conductor
• H01B 7/22 - Metal wires or tapes, e.g. made of steel
• H01B 7/02 - Disposition of insulation
• H01B 3/12 - Insulators or insulating bodies characterised by the insulating materialsSelection of materials for their insulating or dielectric properties mainly consisting of inorganic substances ceramics