AU2001275704A1 - Optical fibre cable - Google Patents
Optical fibre cableInfo
- Publication number
- AU2001275704A1 AU2001275704A1 AU2001275704A AU2001275704A AU2001275704A1 AU 2001275704 A1 AU2001275704 A1 AU 2001275704A1 AU 2001275704 A AU2001275704 A AU 2001275704A AU 2001275704 A AU2001275704 A AU 2001275704A AU 2001275704 A1 AU2001275704 A1 AU 2001275704A1
- Authority
- AU
- Australia
- Prior art keywords
- strength member
- cable
- optical fibre
- central strength
- tube
- 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.)
- Granted
Links
Description
Optical Fibre Cable
This invention relates to optical fibre cable and more particularly
although not exclusively to such cable for blown installation.
One method of installing an optical fibre cable in a duct comprises
blowing the cable into the duct using gaseous flow which is fed into an inlet
end of the duct together with the cable. The length of cable which can be blown into the duct can be increased by applying an additional pushing force
to the cable at the inlet end of the duct. Optical fibre cables for blown installation do not have to withstand high tensile loads (unlike cables which are to be pulled through ducting) but they do require a degree of stiffness for the application of the pushing force.
A design of optical fibre cable marketed by Pirelli Cables Ltd under the designation 'Multi-Element Loose Tube' (MLT) is shown in Figure 1 and
has a core 10 comprising a plurality of tubes 12 stranded about a central, solid strength member 14 and a plurality of optical fibres 16 in each tube 12, and a jacket 18 surrounding said core 10. An aluminium/plastics laminate tape 20
surrounds the tubes to retain the same about the strength member 14 and also to act as a moisture barrier and, because it is electrically conductive, to enable
location of the cable to be detected. Also spaces within each tube which would otherwise be void are filled with a water blocking material 22.
One object of the invention is to provide an optical fibre cable for
blown installation with improved installation performance.
To this end the present invention provides an optical fibre cable having
a core comprising at least one tube stranded about a central strength member
and at least one optical fibre loosely housed in said at least one tube, and a
jacket surrounding said core, wherein said central strength member is tubular,
said central strength member having a peripheral wall enclosing a passage
extending along the length of said central strength member.
The at least one tube stranded about the central strength member need
not contact the central strength member. Thus a sheath may be disposed
between said central strength member and said at least one tube.
The central strength member may be formed in a fibre reinforced
plastics material, for example a glass fibre reinforced plastics material.
At least one elongate element enabling cable location detection may be
accommodated within and extend along the length of said passage of the
central strength member.
Alternatively or additionally at least one tube member loosely housing
at least one optical fibre may be accommodated within and extend along the
length of said passage of the central strength member.
Alternatively or additionally at least one empty tube member for
blown optical fibre installation may be accommodated and extend along the
length of said passage of the central strength member.
In order that the invention may be well understood some embodiments
thereof which are given by way of example only will now be described with
reference to the accompanying drawings in which:
Figure 1 is a radial cross-section of a known optical fibre suitable for
blown installation; and
Figures 2 to 5 are respective radial cross-sections of four optical fibre
cables for blown installation which embody the present invention.
The cables illustrated in Figures 2 to 5 each have a core 100
comprising a plurality of polymeric tubes 112 stranded about a central
strength member 114 and a plurality of optical fibres 116 in each tube 112,
and a polyethylene jacket 118 surrounding the core 100. In each cable, the
central strength member 114 is tubular - the central strength member having a
peripheral wall 119 enclosing a passage 120 extending along the length of the
strength member 114.
A polymeric sheath 121 is disposed between the central strength
member 114 and the tubes 112.
The tubular central strength member 114, which typically has an outer
diameter of 3 to 8 mm and a wall thickness of 0.75 to 2.5 mm, is formed of a
fibre reinforced plastics material such as a glass fibre reinforced plastics
material. However, resin matrices such as carbon and aramid composites may
also be used for the central strength member. The strength member 114 may
be formed with aramid yarn in a stranded layer. It is also envisaged that an
engineering polymer per se may be used. Further the strength member may be
a thin wall metal tube.
Helically wound wrapping tape 122 surrounds the tubes 112 to retain
the tubes 112 which are preferably stranded with an alternating, or so-called
S-Z lay in position against the sheath 121 during manufacturing and handling
of the core. Instead of the wrapping tape, a binding yarn may be used. The
wrapping tape may be made from paper or plastics. Suitable materials include
polyethylene, polyester, water swellable composite structures and metallic
film structures. Typical yarns include polyester, polypropylene and
polyethylene.
The jacket 118 is preferably formed from a high density polyethylene
material and is extruded over the core 100 on which rip cords 124 are
positioned. Water blocking compound 126 is provided in each tube 112 in
any spaces therein which would otherwise be void. Also a water blocking
material 128 is provided between the sheath 121 and the layer defined by the
helically wound wrapping tape or binding yarn in any spaces between the
tubes 112 which would otherwise be void.
It will be noted that a difference between the known design of cable
illustrated in Figure 1 and the cables embodying the invention illustrated in
Figures 2 to 5 is that the central strength member 14 in Figure 1 is solid, ie
formed as a rod whereas the central strength member 114 in each of the
embodiments 'shown in Figures 2 to 5 is tubular. The provision of a tubular
central strength member instead of a solid central strength member reduces
the weight per unit length of the cable whilst increasing its stiffness against
radial deformation on application of a pushing force by a caterpillar device or
the like at the inlet end of the duct into which the cable is being installed
about its central axis. The decrease in weight and the increase in stiffness
each increase the distance to which the cable may be blown.
Figure 2 shows a cable in which the passage 120 of the tubular central
strength member 114 is left void.
Figure 3 shows a cable in which a tube 130 loosely housing a plurality
of optical fibres 132 is accommodated within and extends along the length of
the passage 120. Preferably any spaces within the tube 130 which would
otherwise be void are filled with a water blocking compound.
As will be appreciated, the cable of Figure 3 has a higher number of
optical fibres than that of Figure 2 with no increase in outside diameter of the
cable through its utilisation of the passage 120.
Figure 4 shows a cable in which empty tubes 140 are accommodated
within and extend along the length of the passageway. Each empty tube 140
is able to have an optical fibre blown therein to increase the number of optical
fibres in the cable without increasing its outside diameter.
Figure 5 shows a cable in which a detectable elongate element 150 is
accommodated within and extends along the length of the passage 120. This
element enables the location of the cable when it is buried or otherwise
concealed to be determined. The element 150 preferably comprises an electrically conductive element such as a copper wire or twisted pair.
In the cables shown in Figures 2 to 5 the tubular central strength
member 114 is preferably manufactured by pulltrusion with a cross head feed
for the introduction into the passage 120 of the tube 130 of loosely housed
optical fibres 132 in the case of Figure 3, the empty tubes 140 in the case of
Figure 4 or the detectable elongate element 150 in the case of Figure 5. Alternatively, the tube 130, the tube 140 or the element 150 may be blown
into the passage 120 after manufacture of the tubular strength member 114. In the cables shown in Figures 2 to 5, the aluminium/plastics laminate tape 20 of the cable shown in Figure 1 has been omitted. As stated above, this tape is provided in the cable of Figure 1 to act as a moisture barrier and to enable the location of the cable to be detected. Replacement of this tape 20 with paper or plastics tape 122 or binding yarn reduces the weight of the cable enabling the distance the cable can be blown into a duct of the same internal
diameter to be increased.
Also the presence of the layer of aluminium/plastics laminate provides the cable with a shape memory which hinders unwinding of the cable from a
drum during installation, the unwound cable being blown into the duct tending
to take a spiral rather than straight form. Accordingly replacement of the aluminium/plastics laminate tape 20 with paper or plastics tape 122 or binding
yarn improves the unwinding characteristics of the cable and thus increases
the distance the cable can be blown.
However, it is to be understood that in the embodiments of Figures 2,
3 and 4 the aluminium/plastics laminate tape 20 may be used instead of tape
122 to enable the location of the cable to be determined.
Alternatively the embodiments of Figures 2, 3 and 4 may be modified
to include an elongate element 150 within and extending along the passage
120 for cable location detection.
Whilst a plurality of tubes 112 (shown as twelve) are provided in the cables of Figures 2 to 5, it is to be understood that these cables may be provided with more or less tubes 112 and in an extreme case with only one such tube 112. Similarly, whilst each tube has a plurality of optical fibres (shown as twelve) loosely housed therein it is to be understood that more or less fibres and in an extreme case only one such optical fibre maybe provided within the or each tube 112.
Claims (6)
1. An optical fibre cable having a core comprising at least one tube
stranded about a central strength member and at least one optical fibre loosely
housed in said at least one tube, and a jacket surrounding said core, wherein
said central strength member is tubular, said central strength member having a
peripheral wall enclosing a passage extending along the length of said central
strength member.
2. An optical fibre cable as claimed in claim 1, wherein a sheath is
disposed between said central strength member and said at least one tube.
3. An optical fibre cable as claimed in claim 1 or 2, wherein said central
strength member is formed in a fibre reinforced plastics material.
4. An optical fibre cable as claimed in claim 1, 2 or 3 wherein at least
one elongate element enabling cable location detection is accommodated
within and extends along the length of said passage of the central strength
member.
5. An optical fibre cable as claimed in any one of claims 1 to 4, wherein
at least one tube member loosely housing at least one optical fibre is accommodated within and extends along the length of said passage of the
central strength member.
6. An optical fibre cable as claimed in any one of claims 1 to 5, wherein
at least one empty tube member for blown optical fibre installation is
accommodated and extends along the length of said passage of the central
strength member.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP00306704 | 2000-08-07 | ||
EP00306704.8 | 2000-08-07 | ||
PCT/GB2001/003343 WO2002012943A1 (en) | 2000-08-07 | 2001-07-25 | Optical fibre cable |
Publications (2)
Publication Number | Publication Date |
---|---|
AU2001275704A1 true AU2001275704A1 (en) | 2002-05-16 |
AU2001275704B2 AU2001275704B2 (en) | 2006-06-15 |
Family
ID=8173169
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
AU2001275704A Ceased AU2001275704B2 (en) | 2000-08-07 | 2001-07-25 | Optical fibre cable |
AU7570401A Pending AU7570401A (en) | 2000-08-07 | 2001-07-25 | Optical fibre cable |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
AU7570401A Pending AU7570401A (en) | 2000-08-07 | 2001-07-25 | Optical fibre cable |
Country Status (6)
Country | Link |
---|---|
US (1) | US6876800B2 (en) |
EP (1) | EP1307773A1 (en) |
AR (1) | AR030126A1 (en) |
AU (2) | AU2001275704B2 (en) |
BR (1) | BR0113126A (en) |
WO (1) | WO2002012943A1 (en) |
Families Citing this family (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU2001275704B2 (en) | 2000-08-07 | 2006-06-15 | Prysmian Cables & Systems Limited | Optical fibre cable |
US6654525B2 (en) * | 2001-10-10 | 2003-11-25 | Alcatel | Central strength member with reduced radial stiffness |
US7027697B2 (en) | 2001-12-28 | 2006-04-11 | Pirelli Communications Cables And Systems Usa, Llc | Cable having conduits for receiving optical fibers |
KR100464365B1 (en) * | 2002-08-17 | 2005-01-03 | 삼성전자주식회사 | Air blown fiber optic cable |
DK1480008T3 (en) * | 2003-05-21 | 2015-03-09 | Prysmian Cables & Systems Ltd | Method and apparatus for determining the length of a passage along which an optical fiber is to be blown |
DK1598637T3 (en) * | 2004-05-21 | 2015-11-16 | Prysmian Cables & Systems Ltd | Method and apparatus for determining the length of a section along which an optical fiber is to be blown |
DE102006018536A1 (en) * | 2006-04-21 | 2007-10-25 | CCS Technology, Inc., Wilmington | Optical cable and method of making an optical cable |
US20080240662A1 (en) * | 2007-03-16 | 2008-10-02 | Real Helvenstein | Optical cable for connection to a general distribution network, and a method of connecting said cable |
GB2449941B (en) * | 2007-06-08 | 2011-11-02 | Stingray Geophysical Ltd | Seismic cable structure |
JP5088271B2 (en) * | 2008-08-19 | 2012-12-05 | 富士通株式会社 | Distortion compensator, optical receiver, control method thereof, and optical transmission system |
US20100079248A1 (en) * | 2008-09-29 | 2010-04-01 | Johannes Ian Greveling | Optical fiber connector assembly with wire-based RFID antenna |
TW201038166A (en) * | 2008-11-14 | 2010-10-16 | Corning Inc | Equipment cabinet having improved space utilization |
US8410909B2 (en) | 2010-07-09 | 2013-04-02 | Corning Incorporated | Cables and connector assemblies employing a furcation tube(s) for radio-frequency identification (RFID)-equipped connectors, and related systems and methods |
EP2482110B1 (en) * | 2011-01-28 | 2016-08-24 | CCS Technology, Inc. | Optical assembly and optical cable thereof |
KR101351456B1 (en) * | 2012-04-05 | 2014-01-14 | 엘에스전선 주식회사 | Multi-core optical cable for air blown installation |
EP2850479A4 (en) * | 2012-05-17 | 2016-01-13 | Ofs Fitel Llc | Optical fiber cables with polyethylene binder |
AU2013338389A1 (en) * | 2012-11-05 | 2015-05-28 | Oceaneering International Inc | Method and apparatus for curing of pre impregnated synthetic components in situ |
US10809475B2 (en) | 2014-03-18 | 2020-10-20 | Corning Optical Communications LLC | Jacket for a fiber optic cable |
US10120152B1 (en) * | 2018-02-13 | 2018-11-06 | Superior Essex International LP | All dielectric self-supporting fiber optic cable |
EP4148475A1 (en) | 2021-09-09 | 2023-03-15 | Prysmian S.p.A. | Optical fibre unit for air-blown installation |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0037660A1 (en) * | 1980-04-01 | 1981-10-14 | Pifco Limited | An electric kettle |
US4550976A (en) * | 1984-09-10 | 1985-11-05 | Siecor Corporation | Fiber optic cable with foamed plastic dummy members |
GB9009176D0 (en) | 1990-04-24 | 1990-06-20 | Bicc Plc | Duct for receiving an optical fibre member |
US5046815A (en) * | 1990-05-17 | 1991-09-10 | Corning Incorporated | Optical fiber cabling |
CA2090053C (en) | 1992-03-24 | 1997-10-28 | Lawrence Russell Dunn | Hybrid communications cable for enhancement of transmission capability |
GB2271859B (en) * | 1992-10-21 | 1995-10-18 | Northern Telecom Ltd | Optical fibre cable comprising stack of ribbon fibre elements |
US6169834B1 (en) | 1998-05-13 | 2001-01-02 | Alcatel | Slotted composite cable having a cable housing with a tubular opening for copper pairs and a slot for an optical fiber |
US6195487B1 (en) * | 1998-06-30 | 2001-02-27 | Pirelli Cable Corporation | Composite cable for access networks |
US6101304A (en) * | 1998-10-28 | 2000-08-08 | Sumitomo Electric Lightwave Corp. | Air blown fiber (ABF) tube cable with central innerduct |
EP1004914A1 (en) | 1998-11-25 | 2000-05-31 | Pinacl Communication Systems Ltd | Improvements in and relating to cabling arrangements |
AU2001275704B2 (en) | 2000-08-07 | 2006-06-15 | Prysmian Cables & Systems Limited | Optical fibre cable |
KR100464365B1 (en) * | 2002-08-17 | 2005-01-03 | 삼성전자주식회사 | Air blown fiber optic cable |
-
2001
- 2001-07-25 AU AU2001275704A patent/AU2001275704B2/en not_active Ceased
- 2001-07-25 AU AU7570401A patent/AU7570401A/en active Pending
- 2001-07-25 BR BR0113126-5A patent/BR0113126A/en not_active IP Right Cessation
- 2001-07-25 EP EP01953208A patent/EP1307773A1/en not_active Withdrawn
- 2001-07-25 WO PCT/GB2001/003343 patent/WO2002012943A1/en active Application Filing
- 2001-07-25 US US10/343,907 patent/US6876800B2/en not_active Expired - Fee Related
- 2001-08-07 AR ARP010103763A patent/AR030126A1/en unknown
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6876800B2 (en) | Optical fiber cable | |
AU2001275704A1 (en) | Optical fibre cable | |
US4606604A (en) | Optical fiber submarine cable and method of making | |
EP1203254B1 (en) | Optical fibre cable with single strength member unit in cable outer jacket | |
AU728335B2 (en) | Combination optical fiber cable | |
US5230033A (en) | Subminiature fiber optic submarine cable and method of making | |
US6459837B1 (en) | Optical fiber cable with single strength member unit in cable outer jacket | |
US6137935A (en) | Method for fabricating an optical cable | |
US7027697B2 (en) | Cable having conduits for receiving optical fibers | |
EP0139166B1 (en) | Optical fiber cable | |
CA2324089C (en) | High fiber count, compact, loose tube optical fiber cable employing ribbon units and flexible buffer tubes | |
US7469088B2 (en) | Strengthened optical waveguide fiber cable | |
US6658187B2 (en) | Optical fiber cable assembly with interstitial support members | |
US6996314B2 (en) | Air-blown fiber optic cable | |
US6798958B2 (en) | Cable with a high density of optical fibers | |
US6845789B2 (en) | High density fiber optic cable inner ducts | |
US5777260A (en) | Coaxial cable additionally having at least one light waveguide | |
EP0189666A1 (en) | Optical fibre cables | |
EP0136887A2 (en) | Dielectric optical fibre cable | |
US20060115222A1 (en) | Optical cable having high compression resistance | |
KR20220138307A (en) | Optical cable | |
EP0825465B1 (en) | Single core power cable with an optical fiber element | |
AU2015396467B2 (en) | Aerial optical and electric cable assembly | |
KR200297185Y1 (en) | High-count ribbon optical cable | |
AU2022228174A1 (en) | Optical fibre unit for air-blown installation |