US2131987A - Electric cable with air space insulation - Google Patents

Electric cable with air space insulation Download PDF

Info

Publication number
US2131987A
US2131987A US693212A US69321233A US2131987A US 2131987 A US2131987 A US 2131987A US 693212 A US693212 A US 693212A US 69321233 A US69321233 A US 69321233A US 2131987 A US2131987 A US 2131987A
Authority
US
United States
Prior art keywords
polystyrol
air space
conductors
threads
space insulation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US693212A
Other languages
English (en)
Inventor
Studt Ernst
Traugott Carl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Norddeutsche Seekabelwerke GmbH
Original Assignee
Norddeutsche Seekabelwerke GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Norddeutsche Seekabelwerke GmbH filed Critical Norddeutsche Seekabelwerke GmbH
Application granted granted Critical
Publication of US2131987A publication Critical patent/US2131987A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B11/00—Communication cables or conductors

Definitions

  • the air space insulation of the conductors of the signalling cables is constructed of polystyrol, more particularly by means of threads, cords or bands of polystyrol, which are provided on the conductors, in the same way as paper threads, cords and bands.
  • polystyrol more particularly by means of threads, cords or bands of polystyrol, which are provided on the conductors, in the same way as paper threads, cords and bands.
  • the air space insulation may be constructed, more particularly in the case of land cables, by the simultaneous use of cords and bands of paper and polystyrol, a cord of polystyrol being placed round the copper conductor and a paper band-winding round the said cord.
  • the threads, cords and bands of polystyrol may be suitably used in a profiled form.
  • An air space insulation constructed according to this invention has a dielectric constant which is at least equal to that of paper and air space insulation, Further, the small angle of loss of the polystyrol produces only small dielectric-losses which, more particularly as regards high frequencies, are considerably less than the dielectric loss of paper and air space insulation. This is of special importance in the case of long land and submarine cables, since, as is well known, there is a gradual tendency to utilize the lines in a multiple way, byv employing carrier frequencies, and since, in the case of small specific.
  • a further advantage which results from this property of polystyrol consists in that it becomes possible, in the case of air space insulated submarine cables, to replace the lead sheathing by a covering of gutta-percha or mixtures of polystyrol, gutta-percha, balata, pure or in admixture with caoutchouc, wax or like substances;
  • the endeavours to use a covering of gutta-percha with air space insulated submarine cables have hitherto failed because the hygroscopic paper gradually draws moisture from the gutta-percha covering, whereby its electric properties are impaired.
  • submarine cables, which are paper and air space insulated have always been provided with an enclosing lead sheathing.
  • the air space insulation constructed according to this invention is considerably more resistant to pressures on all sides than paper insulation manufactured in the same way.
  • cables hav- 4 ing conductors which are paper and air insulatedrequire a pressure protecting covering even at water depths of about 70-meters a cable with conductors according to this invention can be used, as has been found by experiments, without 50 any pressure protecting covering at water depths of aboutlOOO meters.
  • spacers provided on the conductors have generally consisted of cords and threads.
  • spacers provided on the conductors have generally consisted of cords and threads.
  • use is made of tubular threads of polystyrol for the production of an air space insulation, instead of solid threads or cords.
  • tubular threads are wound round the cop per conductors. Over this winding, there is then provided, for the completion of the insulation, a band winding or a hose-like covering, for instance of polystyrol.
  • Tubular threads of polystyrol can be manufactured with a very small wall thickness and yet possess throughout sufficient resistance to pressure so that an air space insulation constructed by means of tubular threads has a very small dielectric constant and the angle of loss is far below the value hitherto reached.
  • the air spaces between the individual turns of the winding are filled up by powdered or granular insulating substances of high dielectric values.
  • powdered or granular insulating substances of high dielectric values.
  • Use may be made for this purpose of insulating ceramic materials, of powdered polystyrol, or of amber comminuted to powder.
  • the powdered insulating material may be used in different degrees of fineness, according to the filling factor that is considered suitable in each particular case, for mechanical or dielectric purposes.
  • a further development of the invention relates to the construction of the air space insulation in cables with concentric arrangement of the conductors as used in high frequency transmissions, for instance in carrier frequency telephony or picture transmission.
  • the building up of the air space insulation in such concentric arrangements of conductors use is made of spacers between the inner and the outer conductor, which spacers consist of a material having high insulating properties and a dielectric constant, as small as possible.
  • the spacers are made of polystyrol.
  • polystyrol has the special advantage that in the presence of moisture, its surface is not coated by a continuous layer thereof.
  • the surface resistance of polystyrol therefore, is not substantially reduced even when condensation water from the surrounding moist air is deposited on its surface with'a change in temperature, since the moisture resolves itself into a number of individual small drops which are separated from one another by zones of high surface resistance.
  • Fig. 1 is a perspective view of one form of the cable constructed in accordance with the invention.
  • Fig. 2 is a perspective view illustrating a modifled spacer element.
  • the copper conductor I is surrounded by the thread 2 wound thereon in an open helix, a covering band winding 3 being placed thereon. Both, thread and band, are made of polystyrol.
  • Four conductors, each constructed as just referred to, are stranded to a quad 4 and held together by a band of polystyrol 5.
  • Four such quads stranded together form the cable core, which is surrounded by the water-tight sheathing 6 and the armouring '1.
  • the individual air space insulated conductors of the cable may be insulated in the manner shown in Figure 2.
  • the copper conductor I is surrounded by a tubular thread 8, acting as a spacer, over which the covering 9 is placed, which consists of a tube of polystyrol.
  • Figure 3 illustrates a further modification of the air space insulation which is especially pressure resistant.
  • the copper conductor is surrounded by a thread and a band winding, 2 and 3 respectively.
  • a granular mass it e. g. granular polystyrol, is placed in the gaps between the turns of the thread 2, the said mass preventing the insulation from being compressed.
  • Fig. 4 illustrates a modification of the invention as applied to concentric constructions of conductors.
  • the outer tubular conductor l l is supported by a profile band i5 of polystyrol serving as spacer and laid with a long pitch around the inner conductor I3.
  • the bands and cords of polystyrol or like artificial substance are heated to about 70-80 centigrade, before they are wound on. This may be eifected either by passing the threads or bands, between the storage reel and the winding on device, through a heated tube or, for instance in the manufacture of covered copper conductors, by arranging the Whole of the winding device, including the storage reel, in a heated container.
  • a drawback of the method described consists in that the tensional resistance of the threads decreases with increasing heating, so that the threads can be wound on only at a. low speed it the danger is to be avoided that the threads will break or that their thickness will change during the winding on.
  • the threads 2i are provided with an insertion of tension resisting material, for instance hemp or wire 22. Such threads can be wound on at great speed also when iil in a heated condition, without breaking or without changing their thickness.
  • a central metallic wire In an electrical conductor with air space insulation, a central metallic wire, an open helix of poly'styrol wound around the metal wire, and a covering surrounding said wire and helix, the helix thus forming a spacer between said covering and the metallic wire and providing the air spacing, and the helix oi polystyrol being in the form of a tubular thread with a tension-resistance insertion provided in the interior of said tubular thread.
  • a central metallic wire In an electrical conductor with air space insulation, a central metallic wire, an open helix of polystyrol wound, around the metal wire, and a covering surrounding said wire and helix, the helix thus forming a spacer between said covering and the metallic wire and providing the air spacing, and a granular insulating substance in the free spaces between the turns of the spacer consisting of powdered polystyrol.

Landscapes

  • Insulated Conductors (AREA)
US693212A 1932-10-24 1933-10-11 Electric cable with air space insulation Expired - Lifetime US2131987A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2131987X 1932-10-24

Publications (1)

Publication Number Publication Date
US2131987A true US2131987A (en) 1938-10-04

Family

ID=7986467

Family Applications (1)

Application Number Title Priority Date Filing Date
US693212A Expired - Lifetime US2131987A (en) 1932-10-24 1933-10-11 Electric cable with air space insulation

Country Status (2)

Country Link
US (1) US2131987A (enrdf_load_html_response)
NL (1) NL38079C (enrdf_load_html_response)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2599857A (en) * 1946-01-18 1952-06-10 Telegraph Constr & Main Co Method of manufacture of insulation for coaxial cables
US2873307A (en) * 1953-08-26 1959-02-10 Felten & Guilleaume Carlswerk Deep sea submarine cable
US3117357A (en) * 1961-11-14 1964-01-14 August B Carver Connector for semi-rigid coaxial cable
US3347274A (en) * 1964-02-17 1967-10-17 Stone Straw Corp Tubular bodies, and methods and apparatus for making the same
US3383875A (en) * 1966-08-17 1968-05-21 Andrew Corp Conduit for cryogenic fluids
US3388363A (en) * 1966-02-08 1968-06-11 Square D Co Encapsulated electrical coil and method of making
US3395380A (en) * 1966-03-31 1968-07-30 Lucas Industries Ltd Electrical apparatus
US3592238A (en) * 1969-08-25 1971-07-13 Kabel Metallwerke Ghh Spacer for coaxial pipes
US4220179A (en) * 1975-10-23 1980-09-02 Kabel-Und Metallwerke Gutehoffnungshutte Aktiengesellschaft Spacer for coaxial tube systems

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2599857A (en) * 1946-01-18 1952-06-10 Telegraph Constr & Main Co Method of manufacture of insulation for coaxial cables
US2873307A (en) * 1953-08-26 1959-02-10 Felten & Guilleaume Carlswerk Deep sea submarine cable
US3117357A (en) * 1961-11-14 1964-01-14 August B Carver Connector for semi-rigid coaxial cable
US3347274A (en) * 1964-02-17 1967-10-17 Stone Straw Corp Tubular bodies, and methods and apparatus for making the same
US3388363A (en) * 1966-02-08 1968-06-11 Square D Co Encapsulated electrical coil and method of making
US3395380A (en) * 1966-03-31 1968-07-30 Lucas Industries Ltd Electrical apparatus
US3383875A (en) * 1966-08-17 1968-05-21 Andrew Corp Conduit for cryogenic fluids
US3592238A (en) * 1969-08-25 1971-07-13 Kabel Metallwerke Ghh Spacer for coaxial pipes
US4220179A (en) * 1975-10-23 1980-09-02 Kabel-Und Metallwerke Gutehoffnungshutte Aktiengesellschaft Spacer for coaxial tube systems

Also Published As

Publication number Publication date
NL38079C (enrdf_load_html_response)

Similar Documents

Publication Publication Date Title
US1883269A (en) Electrical conductor
US2454625A (en) Insulated electrical conductor and method of fabricating the same
US3678177A (en) Telecommunication cables
US3649744A (en) Service entrance cable with preformed fiberglass tape
CN108766646A (zh) 一种hdmi光电复合线缆及其制造方法
US2131987A (en) Electric cable with air space insulation
US2718544A (en) Jacketed multiple conductor cable
CN207966534U (zh) 一种hdmi光电复合线缆
GB449582A (en) Improvements in and relating to trunk communication electric cables comprising one or more screened core groups
CN109300587A (zh) 一种阻水型电气化铁路用防霉防鼠防蚁电缆及其制备方法
US4870226A (en) Multi-conductor high voltage cable, in particular three-conductor cable
US2119393A (en) Electric cable and method of manufacturing the same
US1978418A (en) Concentric return multiconductor cable
US2081427A (en) Electric communication cable
CN107958730A (zh) 一种35kv及以下xlpe绝缘热固性护套中压阻水电缆及生产工艺
US2980755A (en) Electric cables
US2189091A (en) Flexible high frequency cable
US1957487A (en) Multicore cable with thermoplastic insulation
RU180122U1 (ru) Кабель для систем железнодорожной сигнализации и блокировки
US3409734A (en) Telephone conductors with longitudinally wrapped and bonded paper tape insulation
US1987442A (en) Signaling cable
US2118907A (en) Multicore high frequency conductor
US2005273A (en) Submarine signaling cable
US2149771A (en) Electric cable
US2289732A (en) Electrical conductor