Exploration • Drilling • Field Services
Picking the correct one of these three options means you will have solved many of your telemetry issues. It is a matter of weighing the tradeoffs required in ruggedness for a given application against cost, convenience, and cable size. Umbilical cable suppliers have the experience to guide you in the best choice for your applications.
Fig. 3. Innovative optical packaging makes application of fiber optics easier. Source: TE Connectivity
● Steel-Light armouring, which uses strands of precisely sized plow steel concentrically arranged around the fibre buffer to protect the fibre from breakage.
● Electro-Light armouring, which is similar to STEEL-LIGHT armouring but uses copper in place of steel. Te copper can also be used for power to allow composite cables to be designed with a smaller outside diameter.
More power in the core As the capabilities of the ROV increase, the power needs of the ROV also increase. Tere are two ways to increase the power-handling capabilities in the core of the umbilical cable. First, you can use conductors of larger cross section. Tis will, however, increase the diameter of the cable. Te second approach is to use thin-wall insulation in place of standard-wall cable. TE Connectivity, for example, uses cross-linked
polyethylene (XLPE) as insulation on power conductors. Tin-wall insulation can achieve cable diameters that are in the range of 30 per cent smaller than comparable standard-wall products. While conventional wisdom dictates that thicker insulation is used as power handling increases, new materials and new processing methods have overturned such wisdom. Tin-wall technology is well established in the
Fig.4. Innovative optical packaging makes application of fiber optics easier. Source: TE Connectivity
Steel-Light and Electro-Light fibre elements are both tight buffered approaches to packaging. Tight buffering, while requiring more careful manufacturing, provides better performance in highly dynamic applications and is the most rugged choice. Steel-Light armouring is the most rugged, designed to withstand hydrostatic pressures of 10,000psi. Both Steel-Light and Electro-Light fibres
(Fig. 3) have very small diameters, allowing them to be fit into interstices in the cable design. With some of newer small-diameter umbilical cables using thin- wall copper conductors, such spaces may not be available. FIST may be a better choice to minimise cable diameter in such cases.
military and aerospace industry, which offers many of the same demands for rugged performance as deepwater applications. Tin-wall insulation has excellent abrasion resistance, excellent thermal stability over a wide temperature range, and electrical properties required for power-carrying applications. With thin-wall-insulated wires, it becomes possible to add additional conductors - and thereby provide more power to the ROV - to the umbilical without increasing its size. Fig. 4 shows an example in which eight thin-wall conductors fit into the same space as seven standard-wall conductors.
Umbilical runs deep As the need increases for deepwater ROVs to support research and oil and gas exploration and production, umbilical cables are supporting the needs for robust performance. New technologies in insulation and optical packaging allow umbilical cables to supply more power to the ROV and to support the increasingly sophisticated capabilities. Tis translates into more capable deepwater devices with a wider range connected by a compact cable delivering more power and more data-handling capabilities. ●
David J Harris, Global Product Director for Marine/Offshore Wire & Cable for TE Connectivity’s Rochester Wire and Cable business unit, Culpeper, Virginia, USA.
www.te.com/adm Article contributors: Mark Casselton, Product Manager - Marine & Offshore Cables, TE Connectivity - Aerospace, Defense & Marine and Sage Wadke, Global Director, Marketing & Business Development, TE Connectivity - Aerospace, Defense & Marine.
22
www.engineerlive.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86