EP0037072A1 - Longitudinally water-blocked cable, especially communication cable - Google Patents
Longitudinally water-blocked cable, especially communication cable Download PDFInfo
- Publication number
- EP0037072A1 EP0037072A1 EP81102246A EP81102246A EP0037072A1 EP 0037072 A1 EP0037072 A1 EP 0037072A1 EP 81102246 A EP81102246 A EP 81102246A EP 81102246 A EP81102246 A EP 81102246A EP 0037072 A1 EP0037072 A1 EP 0037072A1
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- European Patent Office
- Prior art keywords
- cable according
- water
- substance
- gas bubbles
- cable
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- 238000004891 communication Methods 0.000 title claims abstract description 4
- 239000000126 substance Substances 0.000 claims abstract description 52
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- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 12
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- 125000005372 silanol group Chemical group 0.000 claims description 4
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- LIKFHECYJZWXFJ-UHFFFAOYSA-N dimethyldichlorosilane Chemical compound C[Si](C)(Cl)Cl LIKFHECYJZWXFJ-UHFFFAOYSA-N 0.000 description 1
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- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 1
- 125000000896 monocarboxylic acid group Chemical group 0.000 description 1
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Images
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B7/00—Insulated conductors or cables characterised by their form
- H01B7/17—Protection against damage caused by external factors, e.g. sheaths or armouring
- H01B7/28—Protection against damage caused by moisture, corrosion, chemical attack or weather
- H01B7/282—Preventing penetration of fluid, e.g. water or humidity, into conductor or cable
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2933—Coated or with bond, impregnation or core
- Y10T428/2935—Discontinuous or tubular or cellular core
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2933—Coated or with bond, impregnation or core
- Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
- Y10T428/2942—Plural coatings
- Y10T428/2947—Synthetic resin or polymer in plural coatings, each of different type
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2933—Coated or with bond, impregnation or core
- Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
- Y10T428/2942—Plural coatings
- Y10T428/2949—Glass, ceramic or metal oxide in coating
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2933—Coated or with bond, impregnation or core
- Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
- Y10T428/2958—Metal or metal compound in coating
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2973—Particular cross section
- Y10T428/2975—Tubular or cellular
Definitions
- the invention relates to a longitudinally watertight cable, in particular communication cable, in the interior of which a filling compound containing a water-repellent substance is provided, in which gas bubbles are embedded.
- a longitudinally sealed cable of this type is known from DE-OS 27 16 524.
- gas bubbles When gas bubbles are stored, their position in the filling compound is not readily stable and there is therefore a risk that larger gas bubbles may form at certain points due to migration of the gas bubbles, which adversely affect the electrical properties of the cable. It is therefore provided in the known arrangement that the air inclusions are stabilized in their position by supporting components in fiber form.
- the present invention which be on a longitudinally waterproof cable of the type mentioned pulls, the task is to create a cable structure that is easy to manufacture on the one hand and in which on the other hand the filling compound and the enclosed gas bubbles are distributed as evenly as possible, homogeneous in themselves and sufficiently secured against segregation or displacement of the gas bubbles.
- this is achieved in that the filling compound is thickened with a network-forming thixotropic substance, the network of which is torn apart by mechanical action and builds up again in the idle state with a substantial increase in viscosity, and in that the size of the gas bubbles with regard to the tensile strength of the Network structure is chosen so that the buoyancy of the gas bubbles in the rest state of the filling material is significantly below the tensile strength and thereby the position of the gas bubbles in the rest state are secured in a time-stable manner.
- a cable constructed in this way initially has the advantage that the filling compound can be kept very homogeneous because the net-forming thixotropic substance and the water-repellent substance can be mixed very well together with the enclosed gas bubbles and separation does not occur. This applies especially to the gas bubbles, because they are held in the network structure of the thixotropic substance in such a way that migration is not possible in the idle state due to buoyancy forces. It is particularly advantageous that this state of stable storage of the gas bubbles in the filling compound can be ensured solely by the size of the gas bubbles, because only their size determines the buoyancy.
- All those substances can be used for the net-forming thixotropic substance that form spatial networks (frameworks) due to relatively weak, ie non-chemical bonds through agglomeration.
- substances in which dipole interactions or van der Waals forces are effective can also be used for the net-forming connection of the individual basic building blocks. These forces are sufficient to ensure a sufficiently firm cohesion for gas bubbles up to a certain size for the resulting network structures.
- substances which can be used in this context are: finely divided carbon (graphite) and non-annealed A 1 2 0 3 .
- a solution which is particularly advantageous with regard to both the electrical properties of the cable and the processing technology consists in the fact that in the case of the thixotropic substance, the formation of noise is caused by so-called hydrogen bonds.
- a preferred example of this is finely divided amorphous silica, which can be obtained in highly pure form, for example by hydrolysis of silicon tetrachloride in an oxyhydrogen gas flame, and is obtained in spherical particles.
- These spherical particles of the order of a few ⁇ m around have bonds on their surfaces, as shown in FIG. 1 and referred to as silanol groups, that is to say silicon atoms which carry OH groups 1.
- the binding forces between the oxygen and hydrogen atoms shown in dashed lines form the individual basic elements to form a three-dimensional network which, at a sufficiently high concentration, merges into a closed gel structure.
- the schematically indicated buoyancy A of such a gas bubble must remain significantly smaller than the force which exists due to the network structure between the individual basic components (here as a result of the OH bond) if the gas bubbles GB migrate in a time-stable manner should be prevented.
- An excessive amount of admixtures with strongly polar molecules also interferes with the formation of the structure causing the thixotropy in the filling compound. It is therefore recommended to use mainly saturated aliphatic oils without polar side or end groups (ester groups, acid groups, etc.) as the water-repellent substance.
- the filling compound be as free as possible from hydrocarbon halogen or hydrocarbon nitrogen compounds.
- the size of the buoyancy depends on the diameter of the gas bubbles. It is thus particularly easy to set the buoyancy A by the choice of the size of the bubbles so that the net structure cannot be torn by the buoyancy A.
- the still permissible bubble size for a given substance can be determined simply by preparing samples with gas bubbles of different sizes and by observing which diameter value no longer occurs.
- the gas bubbles are sufficiently held in their position by the braking effect of the water-repellent substance. That's why the water-repellent substance should not be chosen too thin.
- a sufficiently high viscosity is achieved in an advantageous manner above all by wax and high molecular weight oil components which are used for the filling compound. Additions of tackifying components (atactic polypropylene, polyisobutylene) can also sufficiently stabilize the foam-like filling compound in the inevitable phases of movement of the cable.
- a correspondingly high viscosity is also e.g. achieved by incorporating particles that are crystalline (low-molecular PE components) or cross-linked (rubber-elastic components).
- the thixotropic agent i.e. in particular the finely divided thixotropic silica can advantageously be added to a water-repellent substance as an additive of up to 20%, preferably between 2 and 6% (percent by weight).
- This water-repellent substance preferably consists of a mixture of saturated liquid and solid hydrocarbons, e.g. made of paraffin wax.
- the water-repellent substance must be selected so that its presence does not prevent the formation of the spatial network structures or that existing spatial network structures are destroyed.
- the presence of water for the formation / spatial network structures in connection with amorphous silica is particularly undesirable because the silanol groups already mentioned are hydrophilic and therefore lose the ability to agglomerate due to excessive water accumulation.
- the substances used for fillers in the cables are water-repellent as much as possible in order to prevent the ingress of water if the sheath is damaged, this measure also ensures that the spatial network structures cannot be destroyed to a large extent by water .
- the water-repellent substance WA therefore has a double function in this context, because it both protects the cable as such from water ingress and at the same time maintains the ability of the thixotropic agent to form network structures.
- the gas bubbles which preferably consist of nitrogen or freon, are distributed as evenly as possible and are present below the permitted size, so that the filling composition as a whole has an approximately foam-like consistency.
- the gas is injected under pressure from the outside via nozzles or the like, and then ensured by an appropriate mixing process that the Distribution of the very small, compressed gas bubbles over the filling compound takes place as evenly as possible.
- the filling material obtained in this way is then inserted into the cable core by means of appropriate filling trumpets or the like and is closed off from the outside by the jacket. The gas bubbles can then expand to their final size due to the decreasing pressure.
- Another possibility is that an additional substance is added to the filling mass, which releases a gas when heated.
- the filling compound only needs to be subsequently heated, for example briefly during the cable manufacturing process, and a sufficient number of gas bubbles, which are usually very small, are released in a sufficient manner.
- the size of the gas bubbles formed is influenced by the pore size of the added material which releases the gas and by the temperature increase and the pressure control.
- the formation of bubbles in the production of the foam-like filling compound is advantageously increased by adding small amounts of nucleating agents (dispersed PE, fluoropolymer or mineral particles).
- the substances is important to ensure that they have a sufficiently high resistivity, for example, at 20 ° C in excess of 10 13 ohm-cm and at 100 ° C or above. 3 10 10 Qcm.
- the filling compound Since water can penetrate if the cable sheath is damaged, which, depending on the nature of the soil, can be slightly acidic or slightly alkaline, special measures must be taken to prevent a harmful influence. This is achieved in that the filling compound, without the thixotropic component, has a certain minimum viscosity in the temperature range from 0 ° C. to 20 ° C. (advantageously above 1000 cP). Furthermore, the filling compound should have no or almost no water-soluble or hydrophilic stock contain or water-friendly molecular groups (OH, COOH, NH 2 groups) and must have the lowest possible wettability against water.
- FIG. 2 shows the shear rate v as a function of the shear stress T in a diagram for the thixotropic substance.
- a deflection remains stable over time, i.e. the spatial network structure does not tear.
- the spatial network structure has been destroyed, so that in the idle state the thixotropic agent together with the enclosed gas bubbles must be sufficiently far below the point X.
- mineral silica derivatives can also be used as thixotropic agents, e.g. Montmorillonite, kaolin and asbestos.
- silica there are other substances that also have the property of agglomeration through hydrogen bonding, in particular the water-mixed oxides B 2 O 3 , P 2 O 5 , Ge 0 2 .
- the hydrogen bonds are not only limited to OH compounds, but can also form between NH-, SH- and halogen H-containing substances. However, these bonds are weaker than those linked via oxygen.
Landscapes
- Insulated Conductors (AREA)
Abstract
Die Erfindung betrifft ein längswasserdichtes Kabel, insbesondere Nachrichtenkabel, in dessen Innerem eine eine wasserabweisende Substanz enthaltende Füllmasse vorgesehen ist, in die Gasbläschen eingelagert sind. Die Füllmasse ist mit einer netzbildenden thoxitropierenden Substanz angedickt, deren Raumnretz bei mechanischer Einwirkung zerrissen wird und sich im Ruhezustand unter wesentlicher Erhöhung der Viskosität wieder aufbaut. Die Größe der Gasbläschen (GB) wird im Hinblick auf die Reißfestigkeit der Netzstruktur so gewählt, daß der Auftrieb (A) der Gasblächen (GE) im Ruhezustand der Füllmasse wesentlich unterhalb der Reißfestigkeit liegt und dadurch die Gasbläschen (GB) im Ruhezustand in ihrer Lage zeitstabil gesichert sind.The invention relates to a longitudinally watertight cable, in particular communication cable, in the interior of which a filling compound containing a water-repellent substance is provided, in which gas bubbles are embedded. The filling compound is thickened with a network-forming thoxitroping substance, the spatial network of which is torn apart by mechanical action and builds up again in the idle state with a substantial increase in viscosity. The size of the gas bubbles (GB) is selected with a view to the tensile strength of the network structure so that the buoyancy (A) of the gas bubbles (GE) when the filling compound is at rest is substantially below the tensile strength and thus the gas bubbles (GB) are in their position when at rest are secured in a stable manner.
Description
Die Erfindung bezieht sich auf ein längswasserdichtes Kabel, insbesondere Nachrichtenkabel, in dessen Innerem eine eine wasserabweisende Substanz enthaltende Füllmasse vorgesehen ist, in die Gasbläschen eingelagert sind.The invention relates to a longitudinally watertight cable, in particular communication cable, in the interior of which a filling compound containing a water-repellent substance is provided, in which gas bubbles are embedded.
Ein längsdichtes Kabel dieser Art ist aus der DE-OS 27 16 524 bekannt. Bei der Einlagerung von Gasbläschen ist deren Lage in der Füllmasse nicht ohne weiteres stabil und es besteht somit die Gefahr, daß durch Wandern der Gasbläschen sich an bestimmten Stellen größere Gasblasen bilden, welche die elektrischen Eigenschaften des Kabels ungünstig beeinflussen. Deshalb ist bei der bekannten Anordnung vorgesehen, daß die Lufteinschlüsse durch stützende Bestandteile in Faserform in ihrer Lage stabilisiert werden.A longitudinally sealed cable of this type is known from DE-OS 27 16 524. When gas bubbles are stored, their position in the filling compound is not readily stable and there is therefore a risk that larger gas bubbles may form at certain points due to migration of the gas bubbles, which adversely affect the electrical properties of the cable. It is therefore provided in the known arrangement that the air inclusions are stabilized in their position by supporting components in fiber form.
Die Aufbereitung dieser beigemischten Fasern und ihre Einbringung in die wasserabweisende Füllmasse erfordern einen zusätzlichen Aufwand, wobei die Wirkung dieser Fasern nur dann gesichert ist, wenn die Fasergröße etwa in der Größenordnung der Bläschengröße liegt. Allzu große Fasern stören zudem die elektrischen Eigenschaften des Kabels in unerwünschter Weise, so daß aufgrund dieser Gesichtspunkte eine sehr feine Auffaserung der zusätzlichen Bestandteile notwendig wird.The preparation of these admixed fibers and their introduction into the water-repellent filling compound require additional effort, the effect of these fibers being ensured only if the fiber size is approximately in the order of the size of the bubbles. Excessively large fibers also undesirably interfere with the electrical properties of the cable, so that a very fine fibering of the additional components is necessary on the basis of these aspects.
Der vorliegenden Erfindung, welche sich auf ein längswasserdichtes Kabel der eingangs genannten Art bezieht, liegt die Aufgabe zugrunde, einen Kabelaufbau zu schaffen, der einerseits einfach herstellbar ist und bei dem andererseits die Füllmasse und auch die eingeschlossenen Gasbläschen möglichst gleichmäßig verteilt, in sich homogen und gegen eine Entmischung oder Verlagerung der Gasbläschen ausreichend gesichert ist. Gemäß der Erfindung wird dies dadurch erreicht, daß die Füllmasse mit einer netzbildenden thixotropierenden Substanz angedickt ist, deren Raumnetz bei mechanischer Einwirkung zerrissen wird und sich im Ruhezustand unter wesentlicher Erhöhung der Viskosität wieder aufbaut, und daß die Größe der Gasbläschen im Hinblick auf die Reißfestigkeit der Netzstruktur so gewählt wird, daß der Auftrieb der Gasbläschen im Ruhezustand der Füllmasse wesentlich unterhalb der Reißfestigkeit liegt und dadurch die Gasbläschen im Ruhezustand in ihrer Lage zeitstabil gesichert sind.The present invention, which be on a longitudinally waterproof cable of the type mentioned pulls, the task is to create a cable structure that is easy to manufacture on the one hand and in which on the other hand the filling compound and the enclosed gas bubbles are distributed as evenly as possible, homogeneous in themselves and sufficiently secured against segregation or displacement of the gas bubbles. According to the invention this is achieved in that the filling compound is thickened with a network-forming thixotropic substance, the network of which is torn apart by mechanical action and builds up again in the idle state with a substantial increase in viscosity, and in that the size of the gas bubbles with regard to the tensile strength of the Network structure is chosen so that the buoyancy of the gas bubbles in the rest state of the filling material is significantly below the tensile strength and thereby the position of the gas bubbles in the rest state are secured in a time-stable manner.
Ein derart aufgebautes Kabel hat zunächst den Vorteil, daß die Füllmasse in sich sehr homogen gehalten werden kann, weil die netzbildende thixotropierende Substanz und die wasserabweisende Substanz zusammen mit den eingeschlossenen Gasbläschen sehr gut miteinander vermischt werden können und eine Entmischung nicht eintritt. Dies gilt vor allem bezüglich der Gasbläschen, weil diese in der Netzstruktur der thixotropierenden Substanz so gehalten werden, daß im Ruhezustand eine Wanderung aufgrund von Auftriebskräften nicht.möglich ist. Dabei ist es von besonderem Vorteil, daß dieser Zustand einer stabilen Einlagerung der Gasbläschen in die Füllmasse allein durch die Größe der Gasbläschen sichergestellt werden kann, weil nur ihre Größe den Auftrieb bestimmt. In diesem Zusammenhang ist es von besonderer Bedeutung, daß die für eine stabile räumliche Einlagerung bei den Gasbläschen notwendigen Durchmesser relativ klein sind, so daß sehr viele sehr kleine Gasbläschen in die Füllmasse eingelagert sind. Dies gibt besonders gute elektrische Eigenschaften und außerdem einen besonders hohen Gasanteil innerhalb der Füllmasse. Letzteres ergibt eine relativ starke Gewichtsverminderung und besonders gute elektrische Eigenschaften des Kabels.A cable constructed in this way initially has the advantage that the filling compound can be kept very homogeneous because the net-forming thixotropic substance and the water-repellent substance can be mixed very well together with the enclosed gas bubbles and separation does not occur. This applies especially to the gas bubbles, because they are held in the network structure of the thixotropic substance in such a way that migration is not possible in the idle state due to buoyancy forces. It is particularly advantageous that this state of stable storage of the gas bubbles in the filling compound can be ensured solely by the size of the gas bubbles, because only their size determines the buoyancy. In this context, it is of particular importance that the need for stable spatial embedding in the gas bubbles Agile diameter are relatively small, so that very many very small gas bubbles are embedded in the filling compound. This gives particularly good electrical properties and also a particularly high proportion of gas within the filling compound. The latter results in a relatively large reduction in weight and particularly good electrical properties of the cable.
Für die netzbildende thixotropierende Substanz können all diejenigen Stoffe verwendet werden, die aufgrund relativer schwacher, d.h. nichtchemischer Bindungen Raumnetze (Gerüste) durch Agglomerieren bilden. Dabei können für die netzbildende Aneinanderlagerung der einzelnen Grundbausteine auch Stoffe verwendet werden, bei denen Dipolwechselwirkungen oder van der Waalssche Kräfte wirksam sind. Diese Kräfte reichen aus, um für die entstehenden Netzstrukturen einen ausreichend festen Zusammenhalt für Gasbläschen bis zu einer gewissen Größe sicherzustellen. Als Beispiele für in diesem Zusammenhang brauchbare Substanzen seien genannt: fein verteilter Kohlenstoff (Graphit)uxünicht geglühtes A1 2 0 3.All those substances can be used for the net-forming thixotropic substance that form spatial networks (frameworks) due to relatively weak, ie non-chemical bonds through agglomeration. In this case, substances in which dipole interactions or van der Waals forces are effective can also be used for the net-forming connection of the individual basic building blocks. These forces are sufficient to ensure a sufficiently firm cohesion for gas bubbles up to a certain size for the resulting network structures. Examples of substances which can be used in this context are: finely divided carbon (graphite) and non-annealed A 1 2 0 3 .
Weiterbildungen der Erfindung sind in den Unteransprüchen wiedergegeben.Developments of the invention are given in the subclaims.
Die Erfindung wird nachfolgend an Hand von Zeichnungen näher erläutert. Es zeigen
- Fig. 1 ein Raumnetz in schematischer Darstellung,
- Fig. 2 in einem Diagramm die Scherspannung in Abhängigkeit von der Schergeschwindigkeit bei einem Thixotropierungsmittel und
- Fig. 3 den Auslenkungswinkel in Abhängigkeit von der Scherspannung.
- 1 is a space network in a schematic representation,
- Fig. 2 in a diagram the shear stress as a function of the shear rate with a thixotropic agent and
- Fig. 3 shows the deflection angle as a function of the shear stress.
Eine im Hinblick sowohl auf die elektrischen Eigenschaften des Kabels als auch auf die Verarbeitungstechnik besonders vorteilhafte Lösung besteht darin, daß bei der thixotropierenden Substanz die-Raunmetzbildung durch sogenannte Wasserstoffbrücken verursacht wird.A solution which is particularly advantageous with regard to both the electrical properties of the cable and the processing technology consists in the fact that in the case of the thixotropic substance, the formation of noise is caused by so-called hydrogen bonds.
Ein bevorzugtes Beispiel hierfür ist feinverteilte amorphe Kieselsäure, die in hochreiner Form z.B. durch Hydrolyse von Siliziumtetrachlorid in einer Knallgasflamme gewonnen werden kann und in kugelförmigen Teilchen anfällt. Diese in der Größenordnung von einigen "um auftretenden kugelförmigen Teilchen tragen an ihren Oberflächen Bindungen, wie sie in Fig. 1 dargestellt sind und als Silanolgruppen bezeichnet werden, d.h. Siliziumatome, welche OH-Gruppen tragen. Mit Hilfe dieser Silanolgruppen verknüpfen sich infolge von in Fig. 1 gestrichelt dargestellten Bindungskräften zwischen den Sauerstoff- und Wasserstoffatomen die einzelnen Grundelemente zu einem dreidimensionalen Netzwerk, das bei einer ausreichend hohen Konzentration in eine geschlossene Gelstruktur übergeht. Innerhalb dieser Gelstruktur, deren Netzaufbau aus Fig. 1 in schematischer Darstellung entnehmbar ist, kann das dargestellte Gasbläschen GB eingeschlossen werden, wobei die schematisch angedeutete Auftriebskraft A eines derartigen Gasbläschens wesentlich kleiner bleiben muß als die Kraft, welche aufgrund der Netzstruktur zwischen den einzelnen Grundbausteinen (hier infolge der OH-Bindung) besteht, wenn zeitstabil ein Wandern der Gasbläschen GB verhindert werden soll. Ein Übermaß an Beimengungen mit stark polaren Molekülen stört in der Füllmasse ebenfalls die Ausbildung des die Thixotropie bewirkenden Gerüstes. Deshalb ist es empfehlenswert, als die wasserabweisende Substanz hauptsächlich gesättigte aliphatische Öle ohne polare Seit-oder Endgruppen (Estergruppen, Säuregruppen usw.) zu benutzen. Aus dem gleichen Grund soll die Füllmasse möglichst frei von Kohlenwasserstoffhalogen- oder Kohlenwasserstoffstickstoffverbindungen sein.A preferred example of this is finely divided amorphous silica, which can be obtained in highly pure form, for example by hydrolysis of silicon tetrachloride in an oxyhydrogen gas flame, and is obtained in spherical particles. These spherical particles of the order of a few µm around have bonds on their surfaces, as shown in FIG. 1 and referred to as silanol groups, that is to say silicon atoms which carry
Die Größe der Auftriebskraft hängt vom Durchmesser der Gasbläschen ab. Es ist somit in besonders einfacher Weise durch die Wahl der Bläschengröße die Auftriebskraft A so einzustellen, daß die Netzstruktur durch die Auftriebskraft A nicht zerrissen werden kann. Im übrigen läßt sich die noch zulässige Bläschengröße für eine gegebene Substanz einfach dadurch bestimmen, daß Proben mit unterschiedlich großen Gasbläschen erstellt werden und durch Beobachtung festgestellt wird, unterhalb welchen Durchmesserwertes keine Wanderung mehr auftritt.The size of the buoyancy depends on the diameter of the gas bubbles. It is thus particularly easy to set the buoyancy A by the choice of the size of the bubbles so that the net structure cannot be torn by the buoyancy A. In addition, the still permissible bubble size for a given substance can be determined simply by preparing samples with gas bubbles of different sizes and by observing which diameter value no longer occurs.
Zwar kommt es, wenn entsprechend große Scherungsbeanspruchungen auftreten, zu einer Zerstörung der in Fig.1 schematisch dargestellten Netzstruktur, so daß sich den Auftriebskräften A der Gasbläschen GB nach Fig. 1 nur noch die Zähigkeit der außerdem noch vorhandenen, durch eine Schraffur angedeuteten wasserabweisenden Substanz WA entgegenstellt. Bei Kabeln ist jedoch zu berücksichtigen, daß diese Scherungsbeanspruchungen normalerweise nur kurzzeitig, z.B. während eines Biegevorganges beim Verlegen auftritt und dann wiederum ein Ruhezustand über sehr lange Zeiträume vorhanden ist. Die thixotropierenden Substanzen, insbesondere die dargestellte Kieselsäure, haben aber die Eigenschaft, daß in dem nach einer derartigen mechanischen Beanspruchung erneut auftretenden Ruhezustand sich die räumlichen Netzstrukturen wieder bilden und deshalb im nachfolgenden Ruhezustand unerwünschte Wanderungsbewegungen der Gasbläschen verhindert werden. Für die Überbrückungszeit werden auch durch die bremsende Wirkung der wasserabweisenden Substanz die Gasbläschen in ihrer Stellung ausreichend festgehalten. Deshalb sollte die wasserabweisende Substanz nicht zu dünnflüssig gewählt werden. Eine ausreichend hohe Viskosität wird vor allem in vorteilhafter Weise durch Wachs und höhermolekulare Ölanteile erreicht, welche für die Füllmasse verwendet werden. Auch Beimischungen von klebrigmachenden Bestandteilen (ataktisches Polypropylen, Polyisobutylen) können die schaumartige Füllmasse in den unvermeidlichen Bewegungsphasen des Kabels ausreichend stabilisieren.If correspondingly large shear stresses occur, the network structure shown schematically in FIG. 1 is destroyed, so that the buoyancy forces A of the gas bubbles GB according to FIG. 1 are only affected by the toughness of the water-repellent substance which is also present and is indicated by hatching WA opposes. In the case of cables, however, it must be taken into account that these shear stresses normally only occur briefly, for example during a bending process during installation, and then there is again a state of rest over very long periods of time. However, the thixotropic substances, in particular the silica shown, have the property that the spatial network structures re-form in the quiescent state that occurs again after such mechanical stress, and therefore undesirable migration movements of the gas bubbles are prevented in the subsequent quiescent state. For the bridging time, the gas bubbles are sufficiently held in their position by the braking effect of the water-repellent substance. That's why the water-repellent substance should not be chosen too thin. A sufficiently high viscosity is achieved in an advantageous manner above all by wax and high molecular weight oil components which are used for the filling compound. Additions of tackifying components (atactic polypropylene, polyisobutylene) can also sufficiently stabilize the foam-like filling compound in the inevitable phases of movement of the cable.
Eine entsprechend hohe Viskosität (pastöse Konsistenz) wird auch z.B. durch Einarbeiten von in sich kristallinen (niedermolekularen PE-Bestandteilen) oder vernetzten (gummielastischen Bestandteilen) Teilchen erreicht.A correspondingly high viscosity (pasty consistency) is also e.g. achieved by incorporating particles that are crystalline (low-molecular PE components) or cross-linked (rubber-elastic components).
Dabei ist zu beachten, daß einerseits die Zeitkonstante, mit der sich die Netzstruktur wiederherstellt, in bezug auf die mögliche Wanderungsgeschwindigkeit der Gasbläschen GB bei zerstörter Netzstruktur so gewählt wird, daß innerhalb der Zeit, in der mechanische Bewegungsvorgänge eine Zerstörung der Netzstruktur herbeigeführt haben, die Wanderungsbewegungen(vorteilhaft unter 1 mm/30 Jahre)in zulässigen Grenzen gehalten werden können, was durch Wahl entsprechender Viskositätswerte möglich ist. Für mögliche Zeitkonstanten für die Wiederherstellung der Netzstruktur kann folgendes angegeben werden:
- Besteht die wasserabweisende Substanz WA in der Füllmasse aus öligen Bestandteilen mit Viskositäten bis etwa 10 000 cP, so sollte diese Zeitkonstante im Bereich von Sekunden oder Minuten liegen. Für zähere Massen mit hohen Wachsanteilen und Viskositäten über 10 000 cP können diese Zeitkonstanten im Bereich von Minuten oder gar mehreren Stunden gewählt werden.
- If the water-repellent substance WA in the filling compound consists of oily constituents with viscosities of up to approximately 10,000 cP, this time constant should be in the range of seconds or minutes. These time constants can be selected in the range of minutes or even several hours for viscous masses with high wax contents and viscosities above 10,000 cP.
Das Thixotropierungsmittel, d.h. insbesondere die feinverteilte thixotropierende Kieselsäure kann vorteilhaft als Zusatz bis zu 20 %, vorzugsweise zwischen 2 und 6 % (Gewichtsprozente) in eine wasserabweisende Substanz eingegeben werden. Diese wasserabweisende Substanz besteht bevorzugt aus einem Gemisch gesättigter flüssiger und fester Kohlenwasserstoffe, z.B. aus Paraffinwachs.The thixotropic agent, i.e. in particular the finely divided thixotropic silica can advantageously be added to a water-repellent substance as an additive of up to 20%, preferably between 2 and 6% (percent by weight). This water-repellent substance preferably consists of a mixture of saturated liquid and solid hydrocarbons, e.g. made of paraffin wax.
Allgemein läßt sich sagen, daß die wasserabweisende Substanz so ausgewählt werden muß, daß durch ihre Anwesenheit nicht die Bildung der Raumnetzstrukturen verhindert wird bzw. vorhandene Raumnetzstrukturen zerstört werden. Beispielsweise ist das Vorhandensein von von Wasser für die Bildung/Raumnetzstrukturen im Zusammenhang mit amorpher Kieselsäure besonders unerwünscht, weil die bereits erwähnten Silanolgruppen hydrophil sind und deshalb durch zu starke Wasseranlagerung die Fähigkeit zur Agglomerierung verlieren. Da jedoch bei den Kabeln die für Füllmassen verwendeten Substanzen ohnehin möglichst stark wasserabweisend sind, um das Eindringen von Wasser bei einer Beschädigung des Mantels zu verhindern, ist durch diese Maßnahme zugleich auch sichergestellt, daß die Raumnetzstrukturen nicht durch hinzutretendes Wasser in größerem Umfang zerstört werden können. Die wasserabweisende Substanz WA hat also in diesem Zusammenhang eine doppelte Funktion, weil sie sowohl das Kabel als solches vor Wassereintritt schützt als auch zugleich die Fähigkeit des Thixotropierungsmittels zur Bildung von Netzstruk-turen erhält.In general it can be said that the water-repellent substance must be selected so that its presence does not prevent the formation of the spatial network structures or that existing spatial network structures are destroyed. For example, the presence of water for the formation / spatial network structures in connection with amorphous silica is particularly undesirable because the silanol groups already mentioned are hydrophilic and therefore lose the ability to agglomerate due to excessive water accumulation. However, since the substances used for fillers in the cables are water-repellent as much as possible in order to prevent the ingress of water if the sheath is damaged, this measure also ensures that the spatial network structures cannot be destroyed to a large extent by water . The water-repellent substance WA therefore has a double function in this context, because it both protects the cable as such from water ingress and at the same time maintains the ability of the thixotropic agent to form network structures.
Es wäre zwar z.B. auch möglich, die Silanolgruppen durch Umsetzen mit siliziumorganischen Verbindungen (z.B. Dimethyldichlorsilan) unwirksam zu machen. Auf diese Weise würde man eine hydrophobe Kieselsäure gewinnen, bei der selbst der Hinzutritt von Wasser keine allzugroße Störung mehr bewirken könnte. Dies würde aber einen zusätzlichen Aufwand bedeuten, der günstiger von der wasserabweisenden Substanz WA innerhalb der Füllmasse übernommen wird.For example, it would also be possible to render the silanol groups ineffective by reacting them with organosilicon compounds (for example dimethyldichlorosilane). In this way you would get a hydrophobic silica, where even the addition of water could no longer cause a major disturbance. However, this would mean an additional effort, which is more favorably carried out by the water-repellent substance WA within the filling compound.
Bei der Herstellung des erfindungsgemäßen Kabels muß darauf geachtet werden, daß die bevorzugt aus Stickstoff oder Freon bestehenden Gasbläschen möglichst gleichmäßig verteilt und unterhalb der zugelassenen Größe vorhanden sind, so daß insgesamt die Füllmasse eine etwa schaumartige Konsistenz aufweist.When manufacturing the cable according to the invention, care must be taken to ensure that the gas bubbles, which preferably consist of nitrogen or freon, are distributed as evenly as possible and are present below the permitted size, so that the filling composition as a whole has an approximately foam-like consistency.
Im einzelnen ergibt sich die Möglichkeit der Fremdbeimischung, d.h in die Füllmasse, welche aus der wasserabweisenden Substanz und der zugefügten thixotropierenden Substanz besteht, wird unter Druck von außen über Düsen oder dergl. das Gas eingepreßt und anschließend durch einen entsprechenden Vermischungsvorgang dafür gesorgt, daß die Verteilung der sehr kleinen, komprimierten Gasblasen über die Füllmasse möglichst gleichmäßig erfolgt. Das so erhaltene Füllmaterial wird dann beim Einpressen in die Kabelseele über entsprechende Fülltrompeten oder dergl. eingegeben und.durch den Mantel nach außen abgeschlossen. Danach können die Gasblasen wegen des absinkenden Druckes auf ihre endgültige Größe expandieren.Specifically, there is the possibility of external admixture, that is, the gas is injected under pressure from the outside via nozzles or the like, and then ensured by an appropriate mixing process that the Distribution of the very small, compressed gas bubbles over the filling compound takes place as evenly as possible. The filling material obtained in this way is then inserted into the cable core by means of appropriate filling trumpets or the like and is closed off from the outside by the jacket. The gas bubbles can then expand to their final size due to the decreasing pressure.
Eine weitere Möglichkeit besteht darin, daß der Füllmasse eine zusätzliche Substanz beigegeben wird, welche bei Erwärmung ein Gas abspaltet. In diesem Fall braucht somit die Füllmasse lediglich nachträglich, z.B. beim Kabelherstellungsprozeß kurzzeitig erwärmt zu werden und es werden in ausreichender Weise sehr viele und meist durch Kennbildner auch sehr kleine Gasbläschen frei. Bei einer entsprechenden Durchmischung ist ebenfalls sichergestellt, daß die Gasbläschen gleichmäßig über die gesamte Füllmasse verteilt sind, wobei durch die Porengröße des zugesetzten, das Gas abspaltenden Materials und durch die Temperaturerhöhung und die Druckführung ein Einfluß darauf genommen werden kann, wie groß die entstehenden Gasbläschen werden.Another possibility is that an additional substance is added to the filling mass, which releases a gas when heated. In this case, the filling compound only needs to be subsequently heated, for example briefly during the cable manufacturing process, and a sufficient number of gas bubbles, which are usually very small, are released in a sufficient manner. With an appropriate mixing is even if it is ensured that the gas bubbles are evenly distributed over the entire filling mass, it being possible for the size of the gas bubbles formed to be influenced by the pore size of the added material which releases the gas and by the temperature increase and the pressure control.
Die Blasenbildung bei der Herstellung der schaumartigen Füllmasse wird vorteilhaft durch Beimischung von geringen Mengen von Keimbildnern (dispergierte PE, Fluorpolymer- oder Mineralstoffteilchen) verstärkt.The formation of bubbles in the production of the foam-like filling compound is advantageously increased by adding small amounts of nucleating agents (dispersed PE, fluoropolymer or mineral particles).
Es ist auch möglich, in den mit der thixotropierenden Substanz vermischten wasserabweisenden Füllmassen durch entsprechend hohen Druck ein Gas zu lösen, wobei während des Herstellungsvorganges oder im Kabel dieser Druck dann erniedrigt wird und durch die Druckerniedrigung der Siedepunkt absinkt, so daß Gasbläschen ebenfalls in sehr feiner Verteilung und mit sehr kleinen Durchmessern freigesetzt werden.It is also possible to dissolve a gas in the water-repellent fillers mixed with the thixotropic substance by correspondingly high pressure, this pressure then being reduced during the production process or in the cable and the boiling point dropping as a result of the pressure drop, so that gas bubbles are also very fine Distribution and can be released with very small diameters.
Bei der Auswahl der Substanzen ist darauf zu achten, daß diese einen ausreichend hohen spezifischen Widerstand haben, der z.B. bei 20° C oberhalb von 1013 Qcm und bei 100° C noch oberhalb von 3 . 1010 Qcm liegt.In the selection of the substances is important to ensure that they have a sufficiently high resistivity, for example, at 20 ° C in excess of 10 13 ohm-cm and at 100 ° C or above. 3 10 10 Qcm.
Da bei Beschädigungen des Kabelmantels u.U. Wasser eindringt, das je nach Bodenbeschaffenheit leicht sauer oder leicht basisch sein kann, müssen besondere Maßnahmen getroffen werden, um hier einen schädlichen Einfluß zu verhindern. Dies wird dadurch erreicht, daß die Füllmasse ohne den thixotropierenden Anteil eine gewisse Mindestviskosität im Temperaturbereich von 0° C bis 20° C aufweist (vorteilhaft über 1000 cP). Weiterhin soll die Füllmasse keine oder möglichst nahezu keine wasserlöslichen oder hydrophilen Bestandteile oder wasserfreundliche Molekülgruppen (OH, COOH, NH2-Gruppen) enthalten und muß eine möglichst niedrige Benetzbarkeit gegen Wasser aufweisen.Since water can penetrate if the cable sheath is damaged, which, depending on the nature of the soil, can be slightly acidic or slightly alkaline, special measures must be taken to prevent a harmful influence. This is achieved in that the filling compound, without the thixotropic component, has a certain minimum viscosity in the temperature range from 0 ° C. to 20 ° C. (advantageously above 1000 cP). Furthermore, the filling compound should have no or almost no water-soluble or hydrophilic stock contain or water-friendly molecular groups (OH, COOH, NH 2 groups) and must have the lowest possible wettability against water.
In Fig. 2 ist in eirem Diagramm für die thixotrpierende Substanz die Schergeschwindigkeit v in Abhängigkeit von der Scherspannung T dargestellt. Bis zum Punkt X der Scherspannung bleibt eine Auslenkung noch zeitstabil, d.h. die Raumnetzstruktur zerreißt nicht. Oberhalb dieses Punktes X ist die Raumnetzstruktur zerstört, so daß im Ruhezustand das Thixotropierungsmittel samt den eingeschlossenen Gasbläschen ausreichend weit unterhalbvom Punkt X liegen muß.2 shows the shear rate v as a function of the shear stress T in a diagram for the thixotropic substance. Up to point X of the shear stress, a deflection remains stable over time, i.e. the spatial network structure does not tear. Above this point X the spatial network structure has been destroyed, so that in the idle state the thixotropic agent together with the enclosed gas bubbles must be sufficiently far below the point X.
In Fig. 3 ist der Auslenkungswinkel a in Abhängigkeit von der Scherspannung T aufgetragen. Auch hier zeigt sich am Punkt X die Änderung des Verhaltens deutlich.3, the deflection angle a is plotted as a function of the shear stress T. Here, too, the change in behavior is clearly evident at point X.
Neben der reinen Kieselsäure kommen auch mineralische Kieselsäureabkömmlinge als Thixotropierungsmittel in Frage, z.B. Montmorillonit, Kaolin und Asbest.In addition to pure silica, mineral silica derivatives can also be used as thixotropic agents, e.g. Montmorillonite, kaolin and asbestos.
Außer der Kieselsäure gibt es noch weitere Substanzen, die ebenfalls die Eigenschaft der Agglomeration durch Wasserstoffbrückenbildung aufweisen, insbesondere die mit Wasser versetzten Oxide B2O3, P2O5, Ge 02.In addition to silica, there are other substances that also have the property of agglomeration through hydrogen bonding, in particular the water-mixed oxides B 2 O 3 , P 2 O 5 ,
Die Wasserstoffbrücken sind nicht nur auf OH-Verbindungen beschränkt, sondern können sich auch ausbilden zwischen NH-, SH- und Halogen H-enthaltenden Substanzen. Diese Bindungen sind jedoch schwächer als bei den über Sauerstoff verknüpften Bindungen.The hydrogen bonds are not only limited to OH compounds, but can also form between NH-, SH- and halogen H-containing substances. However, these bonds are weaker than those linked via oxygen.
Claims (24)
dadurch gekennzeichnet , daß die wasserabweisende Substanz (WA) so gewählt ist, daß durch ihre Anwesenheit nicht die Bildung der Raumnetzstrukturen der thixotropierenden Substanz verhindert wird.8. Cable according to one of the preceding claims,
characterized in that the water-repellent substance (WA) is selected such that its presence does not prevent the formation of the spatial network structures of the thixotropic substance.
dadurch gekennzeichnet , daß die wasserabweisende Substanz (WA) aus einem Gemisch gesättigter flüssiger und fester Kohlenwasserstoffe, insbesondere aus Paraffinwachs besteht.9. Cable according to one of the preceding claims,
characterized in that the water-repellent substance (WA) consists of a mixture of saturated liquid and solid hydrocarbons, in particular paraffin wax.
dadurch gekennzeichnet , daß die wasserabweisende Substanz (WA) aus Wachs und höhermolekularen Ölanteilen besteht.10. Cable according to one of the preceding claims,
characterized in that the water-repellent substance (WA) consists of wax and higher molecular weight oil components.
dadurch gekennzeichnet , daß in der wasserabweisenden Substanz (WA) zusätzlich klebrigmachende Bestandteile vorhanden sind.11. Cable according to one of the preceding claims,
characterized in that the water-repellent substance (WA) additionally contains tackifying constituents.
dadurch gekennzeichnet , daß die wasserabweisende Substanz (WA) aus gesättigten aliphatischen Ölen ohne polare Seit- oder Endgruppen besteht.12. Cable according to one of the preceding claims,
characterized in that the water-repellent substance (WA) consists of saturated aliphatic oils without polar side or end groups.
dadurch gekennzeichnet , daß die Füllmasse keine Kohlenwasserstoffhalogen- oder Kohlenwasserstoffstickstoffverbindungen aufweist.13. Cable according to one of the preceding claims,
characterized in that the filling compound has no hydrocarbon halogen or hydrocarbon nitrogen compounds.
dadurch gekennzeichnet , daß die Füllmasse möglichst keine wasserlöslichen Bestandteile oder wasserfreundlichen Molekülgruppen aufweist.14. Cable according to one of the preceding claims,
characterized in that the filling compound has as far as possible no water-soluble constituents or water-friendly groups of molecules.
dadurch gekennzeichnet , daß die Viskosität der wasserabweisenden Substanz (WA) so gewählt ist, daß in den Zeiträumen, in.welchen die Netzstruktur der thixotropierenden Substanz zerrissen ist, die Gasbläschen (GB) an unzulässig großen Wanderungsbewegungen gehindert sind.15. Cable according to one of the preceding claims,
characterized in that the viscosity of the water-repellent substance (WA) is selected so that in the periods in which the network structure of the thixotropic substance is torn, the gas bubbles (GB) are prevented from impermissibly large migration movements.
dadurch gekennzeichnet, daß die Zeitkonstante für die Wiederherstllung der Netzstruktur bei Viskositäten der wasserabweisenden Substanz (WA) bis etwa 10 000 cP im Bereich von Sekunden oder Minuten gewählt ist.17. Cable according to one of the preceding claims,
characterized in that the time constant for the restoration of the network structure at viscosities of the water-repellent substance (WA) up to approximately 10,000 cP is selected in the range of seconds or minutes.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19803012206 DE3012206A1 (en) | 1980-03-28 | 1980-03-28 | LONG WATERPROOF CABLE, PARTICULARLY MESSAGE CABLE |
| DE3012206 | 1980-03-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP0037072A1 true EP0037072A1 (en) | 1981-10-07 |
Family
ID=6098715
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP81102246A Ceased EP0037072A1 (en) | 1980-03-28 | 1981-03-25 | Longitudinally water-blocked cable, especially communication cable |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US4388485A (en) |
| EP (1) | EP0037072A1 (en) |
| DE (1) | DE3012206A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101248472B1 (en) * | 2013-01-04 | 2013-04-03 | (주)휴바이오메드 | Hemostasis valve |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS587607A (en) * | 1981-07-07 | 1983-01-17 | Sumitomo Electric Ind Ltd | Optical fiber composite overhead line and its manufacture |
| FR2552238B2 (en) * | 1983-09-16 | 1985-10-25 | Cables De Lyon Geoffroy Delore | |
| DE3573478D1 (en) * | 1984-03-03 | 1989-11-09 | Mitsubishi Cable Ind Ltd | Waterproof optical fiber cable |
| US5461195A (en) * | 1986-03-26 | 1995-10-24 | Waterguard Industries, Inc. | Filled telecommunications cable having temperature stable mutual capacitance |
| US5218011A (en) * | 1986-03-26 | 1993-06-08 | Waterguard Industries, Inc. | Composition for protecting the contents of an enclosed space from damage by invasive water |
| US5256705A (en) * | 1986-03-26 | 1993-10-26 | Waterguard Industries, Inc. | Composition with tackifier for protecting communication wires |
| CA1299412C (en) * | 1986-09-19 | 1992-04-28 | Nobuhiro Akasaka | Optical fiber cable preventing water from spreading toward cable interior |
| DE3801409A1 (en) * | 1988-01-15 | 1989-07-27 | Siemens Ag | Fiber optic submarine cable with regenerator supply |
| US7288574B2 (en) * | 2001-07-18 | 2007-10-30 | Eckert C Edward | Two-phase oxygenated solution and method of use |
| US20060030900A1 (en) * | 2001-07-18 | 2006-02-09 | Eckert C E | Two-phase oxygenated solution and method of use |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2019074A1 (en) * | 1970-04-21 | 1971-11-11 | Kabel Metallwerke Ghh | Insulated telephone cable |
| DE2243615A1 (en) * | 1972-09-01 | 1974-03-07 | Siemens Ag | LONGITUDINAL MESSAGE CABLE |
| AT330871B (en) * | 1972-09-21 | 1976-07-26 | Int Standard Electric Corp | MOISTURE-BARRIER FILLER FOR CABLES |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1524124A (en) * | 1920-07-03 | 1925-01-27 | Standard Underground Cable Co Canada | Construction of cables |
| DE1490621B2 (en) * | 1964-07-29 | 1971-10-07 | Siemens AG, 1000 Berlin u 8000 München, se, Puell, Heinz, Dipl Ing , 1000 Berlin | MESSAGE CABLE WITH PLASTIC INSULATED CORES |
| US3576388A (en) * | 1968-12-05 | 1971-04-27 | Stauffer Wacker Silicone Corp | Electrical cable |
| DE2018863A1 (en) * | 1970-04-14 | 1971-10-28 | Ver Draht & Kabelwerke Ag | Longitudinal watertight telecommunication cable |
| NL7117321A (en) * | 1971-12-17 | 1973-06-19 | ||
| CA982804A (en) * | 1972-12-29 | 1976-02-03 | Shirley M. Beach | Composition for filling cables |
| US4110137A (en) * | 1972-12-29 | 1978-08-29 | Phillips Cable Limited | Composition for filling cables |
| US3875323A (en) * | 1973-10-01 | 1975-04-01 | Gen Cable Corp | Waterproof telephone cables with pliable non-flowing filling compound |
| US3893961A (en) * | 1974-01-07 | 1975-07-08 | Basil Vivian Edwin Walton | Telephone cable splice closure filling composition |
-
1980
- 1980-03-28 DE DE19803012206 patent/DE3012206A1/en not_active Ceased
-
1981
- 1981-03-24 US US06/247,078 patent/US4388485A/en not_active Expired - Fee Related
- 1981-03-25 EP EP81102246A patent/EP0037072A1/en not_active Ceased
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2019074A1 (en) * | 1970-04-21 | 1971-11-11 | Kabel Metallwerke Ghh | Insulated telephone cable |
| DE2243615A1 (en) * | 1972-09-01 | 1974-03-07 | Siemens Ag | LONGITUDINAL MESSAGE CABLE |
| AT330871B (en) * | 1972-09-21 | 1976-07-26 | Int Standard Electric Corp | MOISTURE-BARRIER FILLER FOR CABLES |
Non-Patent Citations (1)
| Title |
|---|
| O.A. NEUMULLER " Römpps Chemie Lexikon " , 7. Auflage, Band 6 FRANCKLISCHE VERLAGSHANDLUNG, Stuttgart 1977 Seiten 3888-3889 * Stichwort " Wasserstoffbrückenbindung " * * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101248472B1 (en) * | 2013-01-04 | 2013-04-03 | (주)휴바이오메드 | Hemostasis valve |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3012206A1 (en) | 1981-10-08 |
| US4388485A (en) | 1983-06-14 |
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Legal Events
| Date | Code | Title | Description |
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| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Designated state(s): AT BE CH FR GB IT LU NL SE |
|
| 17P | Request for examination filed |
Effective date: 19811030 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN REFUSED |
|
| 18R | Application refused |
Effective date: 19831027 |
|
| RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: ZEIDLER, GUENTER, DR. DIPL.-ING. Inventor name: LANGE, GERHARD, DIPL.-CHEM. Inventor name: NEY, ERNST, DR. PHIL. CHEM. Inventor name: SALLER, HELMUT |