Welcome to the June edition of the Nexans Technical Review In this issue we will discuss the following topics:

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1 N E X A N S T E C H N I C A L R E V I E W J U N E

2 Table of Contents Welcome to the June edition of the Nexans Technical Review In this issue we will discuss the following topics: 1. OIL & GAS The umbilical system: an important part of a control system 1.1 What is an Umbilical? Construction of an Umbilical Umbilical System Design Norway: the Umbilical s country for Nexans EUROPEAN DIRECTIVE ON CABLE RECYCLING The cable recycling activities of RIPS, a Nexans company 2.1 Cables and recycling Recycling process Plastics separation DATA TRANSMISSION Plastic Optical Fibre (POF): Research for future communications technology 3.1 What is POF? What is the market for POF? Why is Nexans involved in POF? HIGH VOLTAGE CABLE CONNECTIVITY Dry type GIS Sealing End: a new generation of cable terminations The editorial team welcomes your input and feedback. Send your comments to technical.info@nexans.com. We hope you will enjoy reading this Technical Review and look forward to hearing from you. 2

3 1. OIL & GAS The umbilical system: an important part of a control system The oil and gas industry is continuing to reduce costs, improve operational efficiency, and position itself within the energy landscape of the future. The subsea part of the industry is moving into deeper waters ( m), developing new fields, as well as exploiting previously bypassed pockets in existing reservoirs. This article concentrates on the umbilical systems, and their importance within the control systems. 1.1 What is an Umbilical? Typically an umbilical includes tubes, for hydraulic and chemical transport, and electric cables for power and signal, and as such it would be called a electro-hydraulic production control and chemical injection umbilical. Hereafter, it is simply called an umbilical. The electric/hydraulic production control and chemical injection system, hereafter simply called the control system, consists of the following main parts: On the platform (or vessel): Hydraulic Power Unit Electrical Power and Signal Unit Chemicals Facility (storage and pumps) From the platform to the well head: Umbilical System (including dynamic risers as in Fig.1) At the well head, or template: Valves, sensors, subsea control module An umbilical therefore provides remote control of a subsea well head from a platform. 1.2 Construction of an Umbilical An umbilical is a long (2 or 3 km up to >100 km) cylindrical construction of components, designed to be flexible and capable of withstanding tensile, bending and fatigue loads. Figure 1. Floating Production, Storage and Off-loading (FPSO) vessel, with dynamic riser umbilicals, and tethered by anchor lines. An umbilical typically includes components such as: Electric cables Fibre optic cables High pressure tubes Armour wires (to give weight, strength or protection) Fillers (to fill gaps and/or add weight) Wrapping tapes Extruded sheaths (as protective coatings) Every successive layer of components is laid-up contrahelically. An umbilical is required to: Transmit electrical power and signals Transmit hydraulic and chemical fluids at high pressure Interface platform, well head and other equipment Operate without Figure 2. Norne dynamic riser umbilical, Ø180. maintenance (for typical field life of 20 years) in water depths of between 30 meters and >1500 meters. Nexans is currently in the process of manufacturing an umbilical system for 200 meters dynamic service. 3

4 1.3 Umbilical System Design Umbilicals are designed according to a proven philosophy, using a structured approach and strict methodology, together with clearly defined design rules, and a state-of-the-art suite of integrated calculation spreadsheets. In addition to the design rules, Nexans can draw on an extensive data-base derived from many years of umbilical and component qualification testing and field experience. There are four main steps in umbilical design: Determining a feasible cross-section which meets the functional requirements specified by the client Determining the mechanical properties of the umbilical, including axial, bending and torsional stiffness, and the torque balance factor, which describes the umbilical s tendency to twist when tensioned Determining the design s handling limitations in terms of tension, bending and torsion Installation engineering determining the loads the umbilical will be subjected to during installation. These include tension, bending, clamping in the tensioner of the installation vessel, and contact with the chute, stinger or laying wheel of the installation vessel. In the case of a dynamic umbilical, dynamic analyses are performed to provide a basis for the design of the bend stiffener and to verify that the umbilical has an acceptable fatigue life. 1.4 Norway: the Umbilical s country for Nexans Umbilicals are manufactured at Halden, which is the main plant of the Nexans Group for high-voltage and umbilicals and also contains Test and R&D facilities (High-Voltage & Submarine Cables Competence Center). Electric and fibre optic elements are manufactured at Nexans Rognan plant in northern Norway and transported to Halden in preparation of the lay-up of the umbilicals. The lay-up machine can accommodate up to 12 pay-off stands or reels for the main elements, umbilicals with diameters of more than 200 mm can be manufactured. With or without armouring (depending upon the requirements), the umbilical is then provided with outer sheathing and/or wrapping. Among the recent deliveries, one can cite: The deepest installation: meters on Petrobras Roncador field. The longest simple length: 165 km umbilical for Statoil to be delivered by barge, 125 km electric umbilical to Shell s Mensa project, 45 km electro-hydraulic umbilical to Texaco s Gemini. The greatest multiple length: 80 km to Norsk Hydro s Troll oil development. The heaviest umbilical: 123 kg/meter, to Statoil s Asgard project. 4

5 2. EUROPEAN DIRECTIVE ON CABLE RECYCLING The cable recycling activities of RIPS, a Nexans company The european directive on Waste from Electrical and Electronic Equipment (WEEE) provides for re-use, recycling and other forms of recovery of such wastes. This directive (2002/96/EC) was published on February 2003 and it is due to be transposed into national legislation by the end of Cablemakers will not only be responsible for their scraps production (named pre-consumer waste) but also for their products at the end of their lifes. Cable scraps are not ultimate waste (i.e. waste that cannot be recovered at reasonable cost) so they must be recycled. 2.1 Cables and recycling Historically, cable factories have always tried to recover the metallic parts of their scraps which represent an economic issue. To organise this recovery in a structured way, Nexans decided to buy a specialized company named RIPS. RIPS collects, sorts and separates scraps coming from several companies in France and throughout Europe. Generally speaking a cable is made of: Conductor (aluminium or copper) Insulation (polyethylene, PVC, impregnated paper, ) Filler Separator (various papers or textiles) Screen (copper) Armor (steel) Sheath (rubber, PVC, ) The goal of the recycling process is to separate the various elements leading to re-usable products. 2.2 Recycling process After the collection, the sorting operation is of primary importance. As a matter of fact, the better the sorting is the better the end products are. A scraping line consists of the main following steps: Cables are cut into small pieces Grinding into scraps Separation into metal and plastic granulates The metal granulates are sent to foundries but plastics fractions, which are low-grade material, can be used only for a limited range of products (e.g. traffic cones, industrial floorings). In order to enhance the value of the plastic granulates, it is necessary to separate the various components of the mixed plastic waste. 5

6 2.3 Plastics separation Only few companies are able to recycle the mixed plastic granulates. Several processes are proposed: Incineration: Waste incineration is the combustion of waste at high temperatures. It includes a variety ofcombustion systems developed from boiler plant technology and also more novel techniques such as molten salt and fluidised bed incinerators Thermolysis: thermal decomposition of organic material at elevated temperatures in the absence of gases such as air or oxygen. The process, which requires heat, produces a mixture of combustible gases (primarily methane, complex hydrocarbons, hydrogen and carbon monoxide), liquids and solid residues Watech: proprietary process of NKT, only for PVC Vinyloop: low cost, well adapted to PVC-rich compounds Nexans (NRC Lyon) is developing, with the support of a french agency (ADEME), new processes for materials separation (based on electric properties), materials compatibilisation and cross-linked materials processing. Schematic of the Nexans process. 6

7 3. DATA TRANSMISSION Plastic Optical Fibre (POF): Research for future communications technology 3.1 What is POF? POF (Plastic Optical Fibre) has been developed by DuPont in the late 1960s as a medium for illumination. After 30 or so years, a new interest has emerged in short link cabling technologies based on multimode POF for multimedia and data communications. POF offers a viable alternative to copper and glass solutions. At data transmission rates of 100 Mbit/s to 10 Gbit/s, POF can operate faster than usual copper wire and is not sensible to electromagnetic (EM) perturbation. 3.2 What is the market for POF? In the next five years, Local Area Network (LAN) is expected to become a fantastic market where GI POF might substitute a significant part of copper twisted pair and silica multi mode cabling systems. Home networking is also expected to become a major market for POF, which will be driven in the digital age by the increasing audio/video and electronics games systems 3.3 Why is Nexans involved in POF? POF holds the potential to become one of the key technologies in the field of data cable systems, an area where Nexans has a leadership position. For this reason, Nexans wants to become one of the main POF producers in the world, wheras only Japanese companies are operational today. POF is still a R&D project which is carried out by Nexans Research Center (NRC) in Lyon for fluorinated based POF in close collaboration with Nexans Iko Kabel for ribbon manufacturing, and with the Cabling Solutions competence center in Buizingen, cable Plants such as Nexans Harnesses and Draveil for aeronautics applications. 7

8 4. HIGH VOLTAGE CABLE CONNECTIVITY Dry type GIS Sealing End: a new generation of cable terminations Switchgear plays a fundamental role within the power supply industry. It is required to isolate faulty equipment, divide large networks into sections for repair purposes, reconfigure networks in order to restore power supplies and control other equipment. The function of switchgear is to control electric power circuits. This can be subdivided into (a) switching and (b) protection against abnormal conditions. The switching function requires the interruption of currents from zero to full continuous load. The circuit protection function requires the interruption of all currents from small overloads to the maximum short circuit current available at the point of application. More and more Gas Insulated Switchgear (GIS) are installed worldwide, requiring adequate sealing ends for the connection of XLPE insulated High Voltage cables to the switchgear; In the past, traditional oil filled GIS cable terminations have been used for voltages up to 420 kv. A new generation of dry type cable termination has recently been developed by Nexans Suisse and is now available up to 170 kv. The new plug-in design is very compact as well as fluid free and makes the termination maintenance free and environmental friendly. The advantages of the new dry design, compared to traditional oil filled GIS sealing ends are: No internal filling with oil or gas needed Very compact Maintenance and supervision free Plug-in / plug-out possibilities Environment friendly High reliability thanks to prefabricated active parts Easy handling and possibility of installation of epoxy bushing prior to testing of GIS This dry type GIS termination (which corresponds to IEC recommendation 60859) has passed the type test according to IEC for the 170 kv level. Users have now a design which gives them a maximum of installation comfort and security, for the connection of solid type HV cables to GIS. The fact that the new design is very compact, maintenance and supervision free and allowing the connection of cables with conductor cross sections up to 2500 mm 2, makes the new concept attractive compared to traditional oil filled sealing end types. 8

9 Nexans is the worldwide leader in the cable industry, with an industrial presence in 29 countries and commercial activities in 65. The Group employs 17,000 people. Its sales amount to 4 billion Euros. Nexans brings an extensive range of advanced copper and optical fiber cable solutions to the infrastructure, industry and building markets. Its cables and systems can be found in every area of people s lives, from telecommunications and energy networks, to aeronautics, aerospace, automobiles, railways, buildings, petrochemicals, medical applications, etc. Global expert in cables Nexans S.A. - 16, rue de Monceau Paris - France Tel.: +33 (0) Fax: +33 (0) technical.info@nexans.com