EP0000954B1 - Methoden und Apparat zur Kontrolle der Kapazitätsasymmetrie in Bezug auf die Erde, in Kabeln - Google Patents

Methoden und Apparat zur Kontrolle der Kapazitätsasymmetrie in Bezug auf die Erde, in Kabeln Download PDF

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Publication number
EP0000954B1
EP0000954B1 EP78100780A EP78100780A EP0000954B1 EP 0000954 B1 EP0000954 B1 EP 0000954B1 EP 78100780 A EP78100780 A EP 78100780A EP 78100780 A EP78100780 A EP 78100780A EP 0000954 B1 EP0000954 B1 EP 0000954B1
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EP
European Patent Office
Prior art keywords
capacitance
conductor
conductors
ground
unbalance
Prior art date
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Expired
Application number
EP78100780A
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English (en)
French (fr)
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EP0000954A2 (de
EP0000954A3 (en
Inventor
Timothy Stephen Dougherty
William Malcolm Flegal
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AT&T Corp
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Western Electric Co Inc
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Publication date
Application filed by Western Electric Co Inc filed Critical Western Electric Co Inc
Publication of EP0000954A2 publication Critical patent/EP0000954A2/de
Publication of EP0000954A3 publication Critical patent/EP0000954A3/xx
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Publication of EP0000954B1 publication Critical patent/EP0000954B1/de
Expired legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
    • H01B13/06—Insulating conductors or cables
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/58—Testing of lines, cables or conductors
    • G01R31/59—Testing of lines, cables or conductors while the cable continuously passes the testing apparatus, e.g. during manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
    • H01B13/06—Insulating conductors or cables
    • H01B13/14—Insulating conductors or cables by extrusion

Definitions

  • This invention relates to the control of capacitance unbalance-to-ground in cables and, more particularly, to methods of and apparatus for the control of capacitance unbalance-to-ground of twisted conductor pairs in cables having conductors covered with at least a layer of cellular insulation.
  • the conductors After the conductors are insulated with the cellular insulation, they are twisted together in pairs and subsequently formed into a cable. In order to be acceptable, twisted pairs of conductors must exhibit a difference or unbalance in capacitance-to-ground which is less than a predetermined value. Test results show that while the two conductors of any pair may each have acceptable coaxial capacitance and outside diameter values, when twisted together, the pair has unacceptable capacitance unbalance-to-ground values. It had been thought that if measured values of coaxial capacitance and outside diameter of each insulated conductor of a pair fell within acceptable limits, the capacitance unbalance-to-ground would also be acceptable. See Windeler, A. J., Polyethylene Insulated Telephone Cable, 4th Annual Wire and Cable Symposium, December 7, 1955. This seeming anomaly may be overcome by twisting conductors having equal capacitance-to-ground values; however, this requires costly shop control.
  • the problem of being able to maintain the capacitance unbalance-to-ground value of a pair of insulated conductors at less than a predetermined value has been solved by the present invention wherein the application of insulation to conductors is monitored to control the capacitance unbalance-to-ground of each insulated conductor relative to a conductor having preselected values of coaxial capacitance and outside diameter to make it fall within a predetermined range of values.
  • a method embodying the principles of the invention includes the steps of covering conductors with a plastic insulation material to form insulated conductors, measuring the coaxial capacitance and associated outside diameter of the insulated conductors, generating electrical signals which correspond to the measured capacitance and associated diameter of each of the insulated conductors, and relating these signals to the capacitance unbalance-to-ground between each of said conductors and a reference insulated conductor having preselected values of coaxial capacitance and outside diameter, and controlling the covering of the conductors to maintain the capacitance unbalance-to-ground value between each said conductor and the reference conductor within a predetermined range.
  • the generated signals of coaxial capacitance and outside diameter are displayed on a coordinate trace of a continuous recorder with lines of constant percent expansion and constant difference in capacitance-to-ground between insulated conductors and the reference conductor superimposed thereon and related to the values of coaxial capacitance and outside diameter. It has been found that if conductors which are insulated with coordinate values of coaxial capacitance and outside diameter falling within a defined portion of the trace having a predetermined range of capacitance unbalance-to-ground values relative to the reference conductor are twisted together, the capacitance unbalance-to-ground value of the pair is acceptable.
  • An apparatus for controlling capacitance unbalance-to-ground between conductors of a pair includes facilities for extruding cellular insulation over conductors to form insulated conductors, facilities for measuring capacitance and associated outside diameter of the insulated conductors, facilities for displaying measured capacitance and associated diameter with respect to corresponding lines of constant percent expansion and a region defined by spaced lines of constant capacitance unbalance-to-ground values, and facilities for generating a continuous indication of the measured capacitance and associated diameter of the conductors on the displaying facilities, and facilities for controlling at least the percent expansion of the cellular insulation to maintain the coordinate values of coaxial capacitance and diameter within the defined region.
  • the apparatus also includes facilities for twisting together conductors having an insulation identified by capacitance and diameter values falling within the defined region of the trace.
  • a cellular plastic insulation 21 for covering a conductor 22, typically copper or aluminum wire ranging from 0.4064 to 1.1430mm in diameter (see FIG. 1) is well known and is formed from a solid plastic material containing an admixed expanding medium which is extruded about the conductor.
  • FIG.2 there is shown a dual insulated conductor 23 which includes the conductive element. 22 having the cellular insulation 21 and a concentric layer 24 of solid plastic insulation thereabout.
  • the outer layer 24 is comprised, for example, of polyvinyl chloride (PVC) or polyethylene, which forms a thin outer skin 24 that imparts tough mechanical properties to the insulation, that possesses improved voltage breakdown characteristics, and that provides a suitable material for color coding as well as reducing the permeability of the insulation to a filling compound if used.
  • PVC polyvinyl chloride
  • polyethylene which forms a thin outer skin 24 that imparts tough mechanical properties to the insulation, that possesses improved voltage breakdown characteristics, and that provides a suitable material for color coding as well as reducing the permeability of the insulation to a filling compound if used.
  • the outside diameter of the insulated conductor 23 varies between 0.7620 and 2.0320mm while the wall thickness of the outer layer 24 ranges between 0.0508 and 0.1270mm.
  • FIG. 3 there is shown in schematic a view of the two insulated conductors 26 and 27 enclosed in a cable shield 28 for purposes of illustrating capacitance measurements.
  • all the other conductors (not shown) in the cable including the conductor 27 which is twisted together with the conductor 26 are grounded and the capacitance-to-ground of the conductor 26 is measured and designated Cg,.
  • the capacitance-to-ground of a conductor 27, Cg z is measured in a similar manner and the difference (Cg l -Cg,) calculated. This difference is designated as the capacitance unbalance-to-ground.
  • Direct capacitance between the two conductors 26 and 27 is designated C 12 and is added to the series combination of Cg 1 and Cg 2 to obtain a characteristic referred to as mutual capacitance.
  • the capacitance-to-ground characteristic of an insulated conductor is a function of the thickness of the insulation, of the dielectric constant and of the distance of the conductor to the shield. Since, as disclosed by the priorly identified Windeler article, Polyethylene Insulated Cable, the dielectric constant of insulation decreases as the percent voids increase, the capacitance-to-ground value of cellular insulated conductors also varies.
  • cellular insulation includes not only that formed from a solid plastic containing an admixed expanding medium, but also some types of solid insulation, e.g. high density polyethylene (HDPE), where contraction voids occur, generally adjacent to the conductor 22.
  • HDPE high density polyethylene
  • the methods and apparatus of this invention will be described with respect to controlling capacitance-to-ground unbalance in expanded cellular insulation, it should be understood that they are equally applicable to a conductor 22 insulated with a solid plastic insulation which may for example, develop contraction voids and hence acts as an expanded cellular insulation.
  • the insulation 21 may be extruded about the conductor 22 by an apparatus designated generally by the numeral 30, such as that shown in FIG. 4.
  • an apparatus designated generally by the numeral 30, such as that shown in FIG. 4.
  • the following description of the methods and apparatus of this invention will assume that the conductor 23 is being covered with either cellular plastic material 21 or with dual insulating layers 24 and 21 comprising a solid plastic over expanded polyethylene, for example.
  • plastic is intended to include both thermoplastic and thermosetting materials including rubber and rubber-like materials.
  • the conductor 22 is advanced by a capstan 32 through an extruder 31 where the insulation 21 or the dual insulation layers 21 and 24 are applied by a die (not shown) which may be that disclosed and claimed in U.S. patents 3,947,173 and 3,903,233. Then the insulated conductor 23 is advanced out of the extruder 31 and after a predetermined amount of travel through an air-gap distance designated "x", is moved into a cooling trough 33. As can be seen in FIG. 4, the cooling trough 33 is mounted on a gear and rack mechanism 34 for movement reciprocally longitudinally of the path of travel of the conductor 23 so that the air-gap may be adjusted to control the percent expansion of the cellular layer 21.
  • a capacitance monitor 36 measures the coaxial capacitance of the insulation 21 or of the insulation layers 21 and 24 covering the conductive element 22.
  • the capacitance monitor 36 may be of the type shown in U.S. patents 2,765,441 or 2,908,861 or that shown in U.S. patent 2,804,592.
  • the overall diameter do, or diameter-over-dielectric and hereinafter referred to as DOD (see FIGS. 1 and 2), of the insulated conductor 23 is monitored continuously by a gauge 37, such as, for example, an underwater diameter gauge that is manufactured by the Beta Instrument Company and designated model no. TG 1000 or TI500. Typical traces of the overall capacitance C o and the DOD are recorded on a strip chart (not shown).
  • a coordinate chart-recording instrument 50 (see FIG. 4) of the type which is available commercially from the Hewlett-Packard Company, under the description, Model No. 7004B, is used.
  • the instrument 50 has a continuous recorder printer (not shown) which is moved up and down by a current signal from the capacitance monitor 36 and from side to side by a current signal from the DOD gauge 37.
  • a chart 53 is inserted into the instrument 50 for each reel (not shown) of the insulated conductor 23 such that changes in coaxial capacitance and DOD indicated by the position of the recorder printer (not shown) are in direct correspondence with the incremental changes in coaxial capacitance and DOD indicated by the respective monitoring instruments 36 and 37.
  • superimposed upon the chart 53 is an operating window or target area 54 which represents acceptable values of coaxial capacitance and DOD for the insulated conductor 23.
  • the weight of insulation per unit length of dual expanded plastic insulation, the dielectric constants for single layer cellular insulation and for dual insulated conductors, and the percent expansion may be calculated from equations set forth in priorly identified U.S. patents 3,914,352, 3,973,187 and 4,017,228. From these equations, values of coaxial capacitance and DOD may be calculated for weight of insulation and for percent expansion and parallel lines 56-56 of constant weight of insulation, expressed in grams-per-meter for example, of the conductor 23, and parallel lines 57-57 of constant percent expansion are superimposed on the operating window 54.
  • the display of FIG. 4 depicts constant output and constant percent expansion lines superimposed on and in mathematical relationship to a plot of coaxial capacitance versus DOD for cellular plastic insulation.
  • the coaxial capacitance C o and the DOD (see FIGS. 1 and 2) of an insulated conductor are monitored with a continuous indication thereof being conveniently displayed.
  • the display is made in such a way that there is a continuous indication not only of coaxial capacitance and DOD, but also of percent expansion and weight of insulation per foot of the conductor 23.
  • the output of the extruder 31 for the skin layer 24, if used, does not affect the output for the inner cellular layer 21 and that the thickness of the outer layer 24 is essentially constant.
  • the skin thickness (do - d ; )/2 is constant and known and may be measured off-line or by a separate in-line monitor.
  • the composite dielectric constant of the plastic insulation material may be determined, and the total weight includes the weight of the cellular insulation together with the weight of the solid insulation. From instrumentation on the line, the overall coaxial capacitance of the dual insulation and the DOD of the successive sections of the dual insulated conductor 23 are measured.
  • FIG. 5 there are shown coordinate values of coaxial capacitance and DOD for several example conductors 61-65 and, superimposed thereon, the values of capacitance-to-ground differences when two of the conductors, as indicated by a line therebetween, are twisted together. If the conductors 61 and 65 or 61 and 62 which are at the upper left and center or at the upper left and lower right hand corners, respectively, of the graph, are twisted together, the capacitance-to-ground differences are 157 and 174 pF/km. However, if the conductors 63 and 64, which have coordinate values at the upper right and lower left corners of the display the difference in capacitance-to-ground is significantly higher, i.e. 1791 pF/km.
  • the determination of the capacitance unbalance-to-ground values between insulated conductors 23-23 may be made graphically. It has been found that the capacitance unbalance-to-ground between an insulated conductor 23 manufactured as described hereinbefore and the reference insulated conductor 65 having nominal values of coaxial capacitance and DOD may be calculated from the following equation: where
  • the difference in capacitance-to-ground of two insulated conductors which are to be twisted together is obtained by subtracting algebraically the values of the capacitance unbalance-to-ground lines 71-71 or interpolated values between the lines on which the coordinate values of coaxial capacitance and DOD fall.
  • the capacitance unbalance-to-ground between a twisted pair comprising an insulated conductor having coaxial capacitance and DOD values which fall along the line 71 having a scale value of -1.64 pf/m in FIG.6 and an insulated conductor 65 having nominal values is ⁇ 1.64pf/m.
  • a twisted pair of conductors 23-23 each having coordinate values of coaxial capacitance and DOD located along the same one of the lines 71-71 have a zero difference or zero capacitance unbalance-to-ground value.
  • the graph is provided with an operating window 81 which is defined laterally, as viewed in FIG. 7, by two spaced lines 71-71 of constant capacitance unbalance-to-ground values.
  • the lateral boundaries are selected so that if the two insulated 23-23 conductors which are twisted together have coaxial capacitance-DOD coordinate values which fall on the boundary lines, the resulting capacitance unbalance-to-ground of the twisted pair is acceptable.
  • the upper and lower boundaries of the operating window 81 as viewed in FIG. 7 are established to control the mutual capacitance between the two conductors.
  • Each insulated conductor 23 is required to have insulation characteristics such that its coaxial capacitance and DOD fall within the larger rectangular operating window 54 and not necessarily within the precisely defined operating window 81 or 82. Hence, the requirements on operating parameters are relaxed somewhat over the preferred system.
  • Each conductor reel is identified with a capacitance unbalance-to-ground value between it and the reference conductor having the preselected nominal values of coaxial capacitance and outside diameter and at twisting, an operator uses an inventory control system to insure that any two conductors which are twisted together have a minimum difference in capacitance-to-ground. This precaution need not be taken in the preferred system in which any two conductors which pass the operating window test necessarily will have an acceptable capacitance unbalance-to-ground value when twisted together.
  • control exercised by practicing the principles of this invention is a two fold control. Not only is the maximum capacitance unbalance-to-ground value controlled to be within acceptable limits, but also the average capacitance unbalance-to-ground, which has a lower value than the maximum. This is especially important in the use of insulation such as HDPE where the maximum unbalance is not great but where if unchecked, the average is intolerable.
  • the principles of this invention may be extended to a feedback control system to automatically control process variables.
  • the coaxial capacitance and the DOD are measured by the capacitance monitor 36 and the gauge 37, respectively.
  • the measurements are supplied as inputs to the x - y recorder 50 and as inputs to a process control computer, designated generally by the numeral 100.
  • the inputs to the computer 100 which are proportional to the deviation from the nominal values as determined by process specifications cause built-in logic of the computer 100 to establish required correctional signals. These correctional signals are used to vary, for example, the extruder screw speed or to control the mechanism 34 to move the cooling trough 33 and adjust the air gap.
  • the process control computer 100 includes a built-in coordinate plotter which may be in terms of a Cartesian or other convenient coordinate system. In this way, a trace of coaxial capacitance and DOD is reviewed with respect to lines of constant percent expansion, lines of constant insulation weight, and lines of constant capacitance unbalance-to-ground which are programmed into the computer by using the equations referred to hereinbefore. Once the range widths for the capacitance unbalance-to-ground values are set, measurements which are determined to correspond to coaxial capacitance values outside the range cause the computer to control the apparatus 30 to adjust these variables which will change the percent expansion and insulation weight per meter and hence change the coaxial capacitance and DOD.
  • the use of the x - y chart-recording instrument 50 in conjunction with the process control computer 100 permits an operator to observe visually the process conditions and correctional moves made by the computer 100.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)
  • Processes Specially Adapted For Manufacturing Cables (AREA)
  • Measurement Of Resistance Or Impedance (AREA)

Claims (5)

1. Verfahren zur Steuerung der Kapazitätsunsymmetrie gegen Erde zwischen Leitern, bei dem die einzelnen Adern mit einem isolierenden Kunststoffmaterial zur Herstellung isolierter Leiter beschichtet werden, wobei die koaxiale Kapazität und der Außendurchmesser jedes Leiters gemessen und elektrische Signale erzeugt werden, die der gemessenen koaxialen Kapazität und dem gemessenen Außendurchmesser jedes isolierten Leiters entsprechen, dadurch gekennzeichnet, daß diese Signale zur Kapazitätsunsymmetrie gegen Erde zwischen jedem Leiter und einem isolierten Bezugsleiter mit vorgewählten Werten für die koaxiale Kapazität und den Außendurchmesser in Beziehung gesetzt werden, und daß der Beschichtungsvorgang für jeden Leiter so gesteuert wird, daß die Kapazitätsunsymmetrie gegen Erde zwischen jedem einzelnen Leiter und dem Bezugsleiter innerhalb eines vorbestimmten Bereiches von Werten gahelten wird.
2. Verfahren nach Anspruch 1, gekennzeichnet durch die zusätzlichen Verfahrensschritte: Beschichten einzelner Leiter mit wenigstens einer Schicht einer zellförmigen Isolation zur Bildung isolierter Leiter; und Verdrallen von Leitern, zwischen denen eine im wesentlichen vernachlässigbare Kapazitätsunsymmetrie gegen Erde vorhanden ist.
3. Verfahren nach Anspruch 1 oder 2, gekennzeichnet durch die zusätzlichen Verfahrensschritte: Darstellen der gemessenen Koaxialkapazität und des gemessenen Außendurchmessers als Koordinatenwerte einer graphischen Darstellung für die Koaxialkapazität und den Außendurchmesser, wobei der Verfahrensschritt des In-Beziehung-Setzens eine Überlagerung von Linien konstanter Kapazitätsunsymmetrie gegen Erde zwischen einem isolierten Leiter und dem Bezugsleiter in der graphischen Darstellung umfaßt; und Definieren eines Bereichs in der graphischen Darstellung zwischen gewählten Linien konstanter Kapazitätsunsymmetrie gegen Erde;
wobei das Verdrallen so erfolgt, daß Leiter miteinander gepaart werden, die eine gemessene koaxiale Kapazität und einen gemessenen Durchmesser besitzen, welche in den genannten Bereich fallen.
4. Verfahren nach Anspruch 3, gekennzeichnet durch den zusätzlichen Verfahrensschritt: Überlagern in der graphischen Darstellung von Linien konstanter gegenseitiger Kapazität, die zur koazialen Kapazität und zum Außendurchmesser in Beziehung stehen, wodurch der Bereich weiterhin zwischen Linien konstanter gegenseitiger Kapazität definiert wird.
5. Vorrichtung zur Durchführung des Verfahrens nach einem der Ansprüche 1 bis 4, gekennzeichnet durch einen Extruder (31) zur Beschichtung einzelner Leiter mit einem isolierenden Kunststoffmaterial zur Herstellung isolierter Leiter;
eine Überwachungseinrichtung (36, 37) zur Messung der koaxialen Kapazität und des Außendurchmessers jedes Leiters;
eine Einrichtung (36, 37) zur Erzeugung elektrischer Signale, die zur gemessenen koaxialen Kapazität und zum Außendurchmesser jedes isolierten Leiters in Beziehung stehen und zum In-Beziehung-Setzen dieser Signale zur Kapazitätsunsymmetrie gegen Erde zwischen jedem Leiter und einem isolierten Bezugsleiter (65) mit vorgewählten Werten für die koaxiale Kapazität und den Außendurchmesser; und
eine Einrichtung (100), die die Beschichtung jedes Leiters so steuert, daß die Kapazitätsunsymmetrie gegen Erde zwischen jedem Leiter und dem Bezugsleiter innerhalb eines vorbestimmten Bereiches von Werten gehalten wird.
EP78100780A 1977-08-31 1978-08-30 Methoden und Apparat zur Kontrolle der Kapazitätsasymmetrie in Bezug auf die Erde, in Kabeln Expired EP0000954B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US05/829,362 US4174236A (en) 1977-08-31 1977-08-31 Methods of and apparatus for controlling capacitance unbalance-to-ground in cables
US829362 1986-02-14

Publications (3)

Publication Number Publication Date
EP0000954A2 EP0000954A2 (de) 1979-03-07
EP0000954A3 EP0000954A3 (en) 1979-04-04
EP0000954B1 true EP0000954B1 (de) 1981-10-21

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EP78100780A Expired EP0000954B1 (de) 1977-08-31 1978-08-30 Methoden und Apparat zur Kontrolle der Kapazitätsasymmetrie in Bezug auf die Erde, in Kabeln

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Country Link
US (1) US4174236A (de)
EP (1) EP0000954B1 (de)
JP (1) JPS5448086A (de)
CA (1) CA1105594A (de)
DE (1) DE2861199D1 (de)
ES (1) ES473000A1 (de)
IT (1) IT1099315B (de)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4244897A (en) * 1979-03-22 1981-01-13 Measurex Corporation Method and apparatus to control the density of products produced from an extrusion process
US4262164A (en) * 1979-11-27 1981-04-14 Bell Telephone Laboratories, Incorporated Telecommunications multipair cable
US4412094A (en) * 1980-05-21 1983-10-25 Western Electric Company, Inc. Compositely insulated conductor riser cable
US4340554A (en) * 1980-09-29 1982-07-20 Bardwell Robert G Method and apparatus for extrusion coating of a cable involving guider tip protection from an oversized portion of the cable
US4585603A (en) * 1982-03-15 1986-04-29 Showa Electric Wire & Cable Co., Ltd Method for controlling an extrusion line for foamed insulation cables involving use of a plurality of generated and measured electrical signals
GB2130763B (en) * 1982-11-15 1986-05-21 Beta Instr Co Method and apparatus for controlling a cellular foam cable coating extrusion process
US4592881A (en) * 1982-11-15 1986-06-03 Beta Instrument Company Limited Method for controlling a foam resin cable coating extrusion process
US4604497A (en) * 1983-07-28 1986-08-05 Northern Telecom Limited Electrical conductor for telecommunications cable
JP3093518B2 (ja) * 1993-06-02 2000-10-03 株式会社神戸製鋼所 金属線被覆設備の制御方法
JPH07153330A (ja) * 1993-11-29 1995-06-16 Junkosha Co Ltd 同軸ケーブル用コア、これを用いた同軸ケーブル、およびその製造方法
US5814768A (en) * 1996-06-03 1998-09-29 Commscope, Inc. Twisted pairs communications cable
US6140587A (en) * 1997-05-20 2000-10-31 Shaw Industries, Ltd. Twin axial electrical cable
DK1306859T3 (da) * 2001-10-22 2007-05-07 Nexans Kabel med ekstruderet yderkappe og fremgangsmåde til fremstilling af kablet
FI20160270A (fi) * 2016-11-07 2018-05-08 Snow Secure Oy Menetelmä lumen varastointiin

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1047276B (de) * 1958-03-29 1958-12-24 Siemens Ag Verfahren zur automatischen Regelung der Dicke und der Kapazitaet eines mit einem thermoplastischen Kunststoff umspritzten elektrischen Leiters
CH462910A (de) * 1967-02-13 1968-09-30 Gen Cable Corp Verfahren und Vorrichtung zum Aufbringen von Kunststoffschichten auf einen elektrischen Leiter
US3914357A (en) * 1973-01-04 1975-10-21 Western Electric Co Method of monitoring the application of cellular plastic insulation to elongated conductive material
US4017228A (en) * 1973-01-04 1977-04-12 Western Electric Company, Inc. Apparatus for monitoring cellular dielectric material
US3973187A (en) * 1973-01-04 1976-08-03 Western Electric Company, Inc. Sensing capacitance and thickness of insulated cable to provide outputs related to weigh and percent voids
DE2405654A1 (de) * 1974-02-04 1975-08-07 Siemens Ag Verfahren zur konstanthaltung der abmessungen und elektrischen eigenschaften von kabeladern mit verzellter kunststoffisolierung bei deren herstellung durch extrusion
CA1087712A (en) * 1976-11-01 1980-10-14 Northern Telecom Limited Control for wire coating line

Also Published As

Publication number Publication date
US4174236A (en) 1979-11-13
IT1099315B (it) 1985-09-18
DE2861199D1 (en) 1981-12-24
IT7827163A0 (it) 1978-08-30
JPS5448086A (en) 1979-04-16
EP0000954A2 (de) 1979-03-07
JPS6235208B2 (de) 1987-07-31
CA1105594A (en) 1981-07-21
EP0000954A3 (en) 1979-04-04
ES473000A1 (es) 1979-03-16

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