China
Africa
Explore chapters and articles related to this topic
Conductors
Published in Anthony J. Pansini, Electrical Distribution Engineering, 2020
The advantages of steel for strength and copper for conductivity are combined into a solid nonstranded-type copper-clad steel conductor. Obviously, this type of conductor is limited to the smaller-size copper conductor equivalents. The layer of copper is continuously bonded to the steel, resulting in a material that is essentially homogeneous. Such conductors are made in two grades of conductivity, 30 and 40 percent copper (as a percentage conductivity compared to the conductivity of hard- drawn copper of the same cross section) and in two grades of strength depending on the grade of steel around which the copper is placed. The copper covering acts to insure the conductors against destructive corrosion. This type of conductor is handled in the same manner as solid-type hard-drawn copper conductors.
Substation Grounding
Published in John D. McDonald, Electric Power Substations Engineering, 2017
Copper is a common material used for grounding. Copper conductors, in addition to their high conductivity, have the advantage of being resistant to most underground corrosion because copper is cathodic with respect to most other metals that are likely to be buried in the vicinity. Copper-clad steel is usually used for ground rods and occasionally for grid conductors, especially where theft is a problem. Use of copper, or to a lesser degree copper-clad steel, therefore assures that the integrity of an underground network will be maintained for years, so long as the conductors are of an adequate size and not damaged and the soil conditions are not corrosive to the material used. Aluminum is used for ground grids less frequently. Though at first glance the use of aluminum would be a natural choice for GIS equipment with enclosures made of aluminum or aluminum alloys, there are several disadvantages to consider: Aluminum can corrode in certain soils. The layer of corroded aluminum material is nonconductive for all practical grounding purposes.Gradual corrosion caused by alternating currents can also be a problem under certain conditions.
5 Grounding and Bonding
Published in C. Sankaran, Power Quality, 2017
Typically, copper-clad steel rods are used for ground rods. Steel provides the strength needed to withstand the forces during driving of the rod into the soil, while the copper coating provides corrosion protection and also allows copper conductors to be attached to the ground rod. The values indicated above are the minimum values; depending on the installation and the type of soil encountered, larger and longer rods or pipes may be needed. Table 5.6 shows earth resistance variation with the length of the ground rod, and Table 5.7 shows earth resistance values for ground rods of various diameters. The values are shown for a soil with a typical ground resistivity of 10,000 Ω-cm.
Research on earth surface potential distribution and amendment for soil resistivity horizontal hierarchical model in current inflow test
Published in Australian Journal of Electrical and Electronics Engineering, 2018
Li Qiu, Liyang Huang, Yao Xiao, Pan Su, Jie Yang, Bin Peng, Qi Xiong, Xiwu Zhao, Changzheng Deng
The inflow electrode in the actual current inflow test is a ring-shaped horizontal electrode with the diameter of 10 m which is made by round steel. Four insulated wires are used to symmetrically connect with the ring-shaped electrode and lead out to the ground. The electrode is buried in approximately 1 m in depth. The auxiliary electrode adopts 10 copper clad steel electrodes with the diameter of 38 mm. The circuit between the two electrodes is an insulated wire with a cross-sectional area of 4 mm2 and a length of 10 km. The test uses DC power supply with the output voltage of 550 V and output current of approximately 5 A. Figure 3 is the path of the actual current inflow test in Yi’an Chong electrode site.
Recovery of copper and aluminium from coaxial cable wastes using comparative mechanical processes analysis
Published in Environmental Technology, 2021
Thiago R. Martins, Natani S. Mrozinski, Daniel A. Bertuol, Eduardo H. Tanabe
Although not performed on this study, a possible approach that could be used for the recycling of coaxial cables would be comminution + sieving + magnetic separation. Sieving would recover the aluminium from the mixture, while magnetic separation would recover the copper-clad steel. The disadvantage of this technique for coaxial cable recycling is the incapability of recovering materials other than copper-clad steel, highly magnetic. Therefore, any other remaining metallic material, such as copper or aluminium, would not be recovered without an electrostatic separation step.
Investigation wavy interface forming and stretching in severe plastic deformed copper/steel bimetallic rod
Published in Mechanics of Advanced Materials and Structures, 2021
Historically, more than 150 years have passed since the first recorded attempt to make copper clad steel products [11]. Many different production methods have been introduced by scholars as well as the various equipment and technologies that have been put into operation by manufacturing companies worldwide since then. Preparation methods and their advantages and drawback have been documented by Refs [12–14] for copper-clad steel wire which is recently well-reviewed by Wang et al. [1] for copper/steel composites products. According to their classification, three main categories of bimetallic copper/steel preparation techniques and their related subclasses methods, to put it briefly, including: a) the liquid-liquid phase preparation methods include molding transformation and double molten metal(continuous casting with level magnetic field brake) methods, b) the liquid-solid phase preparation methods include the chemical and electrochemical plating from aqueous- and non-aqueous solutions, traditional casting method(directly cast molten copper alloys into the steel molding), hot-dip coating in melted copper (reverse solidification or freezing method), and continuous casting/rolling(combining cast and the rolling method), flexible tool cladding (FTC) method, laser cladding process, pulsed-current gas metal arc welding and metal spraying techniques, c) the solid-solid phase production methods include: continuous extrusion, hot extrusion welding, hot rolling, cold rolling, asymmetrical rolling, vacuum rolling, drawing, mechanical swell shipping, bulging hydraulic, clad-welding, explosive welding, hot isostatic pressing, friction stir welding (FSW) and powder metallurgy methods. In solid-solid phase production processes, the bonding between copper and steel in their interfaces is achieved by ordinary plastic deformation, except the FSW method in which the bimetallic material undergoes severe plastic deformation (SPD).