1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T L.108 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (03/2018) SERIES L: ENVIRONMENT AND ICTS, CLIMATE CHANGE, E-WASTE, ENERGY EFFICIENCY; CONSTRUCTION, INSTALLATION AND PROTECTION OF CABLES AND OTHER ELEMENTS OF OUTSIDE P
2、LANT Optical fibre cables Cable structure and characteristics Optical fibre cable elements for microduct blowing-installation application Recommendation ITU-T L.108 ITU-T L-SERIES RECOMMENDATIONS ENVIRONMENT AND ICTS, CLIMATE CHANGE, E-WASTE, ENERGY EFFICIENCY; CONSTRUCTION, INSTALLATION AND PROTECT
3、ION OF CABLES AND OTHER ELEMENTS OF OUTSIDE PLANT OPTICAL FIBRE CABLES Cable structure and characteristics L.100L.124 Cable evaluation L.125L.149 Guidance and installation technique L.150L.199 OPTICAL INFRASTRUCTURES Infrastructure including node elements (except cables) L.200L.249 General aspects a
4、nd network design L.250L.299 MAINTENANCE AND OPERATION Optical fibre cable maintenance L.300L.329 Infrastructure maintenance L.330L.349 Operation support and infrastructure management L.350L.379 Disaster management L.380L.399 PASSIVE OPTICAL DEVICES L.400L.429 MARINIZED TERRESTRIAL CABLES L.430L.449
5、 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T L.108 (03/2018) i Recommendation ITU-T L.108 Optical fibre cable elements for microduct blowing-installation application Summary Recommendation ITU-T L.108 (ex. L.79) describes the characteristics, construction and t
6、est methods for microduct fibre units and microduct cables that are used with the blowing installation technique. The cable characteristics required for a cable to perform appropriately are described. Also, a method is described for determining whether or not the cable has the required characteristi
7、cs. The required conditions may differ according to the installation environment; detailed test conditions must be agreed upon between a user and a manufacturer for the environment in which a cable is to be used. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T L.108/L.79 200
8、8-07-07 6 11.1002/1000/9429 2.0 ITU-T L.108 2018-03-16 15 11.1002/1000/13565 Keywords Blowing installation, fibre unit, microcable, microduct, optical fibre cable. _ * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommend
9、ations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T L.108 (03/2018) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Te
10、lecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardizatio
11、n Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technolo
12、gy which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance
13、with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligato
14、ry language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of
15、 this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the
16、date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to cons
17、ult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2018 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T L.108 (03/2018) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definit
18、ions 3 3.1 Terms defined elsewhere 3 3.2 Terms defined in this Recommendation . 3 4 Abbreviations and acronyms 4 5 Conventions 4 6 Environmental conditions . 4 6.1 Underground . 4 6.2 Aerial 4 6.3 Indoor . 4 7 Construction and characteristics of microduct system and cable elements 4 7.1 Fibre 4 7.2
19、Blown-in elements 5 7.3 Microducts 6 7.4 Protected microducts 6 7.5 Composite protected microduct/cable 7 8 Test methods . 7 8.1 Test methods for dimensions 7 8.2 Test methods for cable elements 7 8.3 Methods for testing mechanical characteristics 8 8.4 Test methods for environmental characteristics
20、 . 10 8.5 Test methods for fire safety 11 8.6 Test methods for installation performance . 11 Appendix I Chinese experience 12 I.1 Product types of microducts . 12 I.2 Microduct inner clearance verification . 13 I.3 Blowing performance test for microcables or fibre units in microduct 14 I.4 Layout lo
21、cation selection for microduct . 16 Appendix II Chinese experience on effects of freezing conditions on microduct air-blown cables . 17 II.1 Introduction 17 II.2 Freezing test 17 II.3 Conclusion 20 Bibliography. 21 iv Rec. ITU-T L.108 (03/2018) Introduction Air blowing installation methods are based
22、 on viscous drag acting upon a cable within a duct by forcing a continuous high-speed airflow through the duct. The velocity of the moving air propels the cable and makes it advance at a typical speed supported by the blowing equipment. When using blowing techniques, there is generally no pulling fo
23、rce at the front end of the cable; the airflow exerts a distributed force along the entire cable. In addition, connection to a pulling cord is not needed. Generally, the blowing force is an order of magnitude lower than the typical force involved in other installation methods, for example pulling te
24、chniques, thus reducing installation hazards. Additionally, with this technique, bends in a duct run are of less concern than with pulling techniques, so, generally, the installation speed increases and longer lengths of cable can be installed. Cables are installed with low stress levels, leaving th
25、e cable or other elements effectively relaxed in the duct once the installation has been completed. Therefore, cables can be designed with lower tensile capabilities than cables to be pulled. And, elements without additional strength members, such as fibre units and single fibres, can also be consid
26、ered. New generation cabling techniques, based on microduct cables, microduct fibre units and microduct systems, offer the possibility of branching without the need for splices. These techniques are extremely flexible and make them possible to grow in accordance with demand. This gives rise to the c
27、oncept of “fibre on demand“, which involves the pre-installation of a multi-microduct system and then the subsequent, incremental installation of fibres based on individual customer demand. To support this “fibre on demand“ approach, a fibre cable product must allow the installation of only a few fi
28、bres at a time. These types of cable products should take up the smallest possible amount of the service providers right-of-way (i.e., fit the smallest microduct) so that there is plenty of space to add fibres for future customers. Therefore, usually only a small number of the fibres that are instal
29、led are used immediately. Also, the latest fibre technology can be adopted when required. Rec. ITU-T L.108 (03/2018) 1 Recommendation ITU-T L.108 Optical fibre cable elements for microduct blowing-installation application 1 Scope This Recommendation: refers to microduct fibre units and microduct cab
30、les to be used for telecommunication networks with blowing installation techniques; deals with mechanical and environmental characteristics of microduct fibre units and microduct cables. The optical fibre dimensional and performance parameters, together with their test methods, should comply with IE
31、C 60793-5-10 or IEC 60794-5-20 which deal with microduct cable and microduct fibre units, respectively. The optical fibre dimensional and transmission characteristics, together with their test methods, should comply with IEC 60793-2-10 and with ITU-T G.651.1, ITU-T G.652, ITU-T G.653, ITU-T G.654, I
32、TU-T G.655, ITU-T G.656 and ITU-T G.657 which deal with multi-mode graded index optical fibres and single-mode optical fibres, respectively; acknowledges that some optical fibre cables may contain metallic elements, for which reference should be made to b-ITU-T Technical Report and other L-series Re
33、commendations. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are sub
34、ject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document
35、 within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T G.650.1 Recommendation ITU-T G.650.1 (2018), Definitions and test methods for linear, deterministic attributes of single-mode fibre and cable. ITU-T G.651.1 Recommendation ITU-T G.651.1 (20
36、07), Characteristics of a 50/125 m multimode graded index optical fibre cable for the optical access network. ITU-T G.652 Recommendation ITU-T G.652 (2016), Characteristics of a single-mode optical fibre and cable. ITU-T G.653 Recommendation ITU-T G.653 (2010), Characteristics of a dispersion-shifte
37、d single-mode optical fibre and cable. ITU-T G.654 Recommendation ITU-T G.654 (2016), Characteristics of a cut-off shifted single-mode optical fibre and cable. ITU-T G.655 Recommendation ITU-T G.655 (2009), Characteristics of a non-zero dispersion-shifted single-mode optical fibre and cable. ITU-T G
38、.656 Recommendation ITU-T G.656 (2010), Characteristics of a fibre and cable with non-zero dispersion for wideband optical transport. ITU-T G.657 Recommendation ITU-T G.657 (2016), Characteristics of a bending loss insensitive single mode optical fibre and cable. 2 Rec. ITU-T L.108 (03/2018) ITU-T L
39、.100 Recommendation ITU-T L.100/L.10 (2015), Optical fibre cables for duct and tunnel application. ITU-T L.101 Recommendation ITU-T L.101/L.43 (2015), Optical fibre cables for buried application. ITU-T L.102 Recommendation ITU-T L.102/L.26 (2015), Optical fibre cables for aerial application. ITU-T L
40、.103 Recommendation ITU-T L.103/L.59 (2016), Optical fibre cables for indoor applications. ITU-T L.162 Recommendation ITU-T L.162 (2016), Microduct technology and its applications. ITU-T L.400 Recommendation ITU-T L.400/L.12 (2008), Optical fibre splices. IEC 60189-1 IEC 60189-1 (2007), Low-frequenc
41、y cables and wires with PVC insulation and PVC sheath Part 1: General test and measuring methods. IEC 60793-1-1 IEC 60793-1-1 (2017), Optical fibres Part 1-1: Measurement methods and test procedures General and guidance. IEC 60793-1-20 IEC 60793-1-20 (2016), Optical fibres Part 1-20: Measurement met
42、hods and test procedures Fibre geometry. IEC 60793-1-21 IEC 60793-1-21 (2001), Optical fibres Part 1-21: Measurement methods and test procedures Coating geometry. IEC 60793-1-32 IEC 60793-1-32 (2010), Optical fibres Part 1-32: Measurement methods and test procedures Coating strippability. IEC 60793-
43、1-53 IEC 60793-1-53 (2014), Optical fibres Part 1-53: Measurement methods and test procedures Water immersion tests. IEC 60793-2-10 IEC 60793-2-10 (2017), Optical fibres Part 2-10: Product specifications Sectional specification for category A1 multimode fibres. IEC 60794-1-1 IEC 60794-1-1 (2015), Op
44、tical fibre cables Part 1-1: Generic specification General. IEC 60794-1-2 IEC 60794-1-2 (2017), Optical fibre cables Part 1-2: Generic specification Basic optical cable test procedures General guidance. IEC 60794-1-21 IEC 60794-1-21 (2015), Optical fibre cables Part 1-21: Generic specification Basic
45、 optical cable test procedures Mechanical tests methods. IEC 60794-1-22 IEC 60794-1-22 (2012), Optical fibre cables Part 1-22: Generic specification Basic optical cable test procedures Environmental test methods. IEC 60794-1-23 IEC 60794-1-23 (2012), Optical fibre cables Part 1-23: Generic specifica
46、tion Basic optical cable test procedures Cable element test methods. IEC 60794-5 IEC 60794-5 (2014), Optical fibre cables Part 5: Sectional specification Microduct cabling for installation by blowing. IEC 60794-5-10 IEC 60794-5-10 (2014), Optical fibre cables Part 5-10: Family specification - Outdoo
47、r microduct optical fibre cables, microducts and protected microducts for installation by blowing. IEC 60794-5-20 IEC 60794-5-20 (2014), Optical fibre cables Part 5-20: Family specification Outdoor microduct fibre units, microducts and protected microducts for installation by blowing. Rec. ITU-T L.1
48、08 (03/2018) 3 IEC/TR 62222 IEC/TR 62222 (2012), Fire performance of communication cables installed in buildings. 3 Definitions 3.1 Terms defined elsewhere For the purpose of this Recommendation, the definitions given in ITU-T G.650.1 and ITU-T G.651.1 apply. 3.2 Terms defined in this Recommendation
49、 This Recommendation defines the following terms: 3.2.1 blowing duct: There are three kinds of blowing ducts: outer protective duct, protected microduct and composite protected microduct/cable. 3.2.2 blown-in element: A blown-in element consists of optical fibre(s), sheath and other materials and can be inserted into the microduct by continuous high-speed airflow force. Som
