The Experts below are selected from a list of 204 Experts worldwide ranked by ideXlab platform

B.s. Wyatt - One of the best experts on this subject based on the ideXlab platform.

  • Cathodic Protection Instrumentation
    Shreir's Corrosion, 2020
    Co-Authors: B.s. Wyatt
    Abstract:

    A number of measurements, principally electrical, are necessary in order to collect data for the design of a Cathodic Protection system, to monitor the installation parameters as it is being installed, and to assess the performance of the system during its commissioning, testing, and thereafter. Additional measurements are also required to determine the effects of the Cathodic Protection system on other structures. This chapter deals with the instruments used for taking these measurements and indicates in general terms the various types of instrumentation available to corrosion engineers today. Brief details of instruments not directly connected with Cathodic Protection as such, but nevertheless associated with it, are also included.

  • Practical Application of Cathodic Protection
    Shreir's Corrosion, 2020
    Co-Authors: B.s. Wyatt
    Abstract:

    In principle, Cathodic Protection can be used for a variety of applications where a metal is buried, immersed, or encased in an aqueous solution of an electrolyte, which can range from soils, relatively pure water, seawater, and dilute solutions of acids to concrete. Whether the method is applicable will depend on many factors and, in particular, economics; Cathodic Protection of steel immersed in a highly acidic solution is theoretically feasible but is generally too costly to be practicable. It should be emphasized that as the method is electrochemical, both the structure to be protected and the anode used for Protection must be in both metallic and electrolytic contact. Cathodic Protection cannot therefore be applied for controlling atmospheric corrosion, since it is not feasible to immerse an anode in a thin condensed film of moisture or in droplets of rain water. Further, Cathodic Protection to the external surfaces of a pipeline will not provide corrosion Protection to the internal surfaces. This section deals exclusively with the practical application of Cathodic Protection principally using the impressed-current Cathodic Protection. The application of Cathodic Protection using galvanic (or galvanic) anodes of aluminum, zinc, and magnesium, which themselves corrode preferentially to the material being protected and do not require an external (or impressed) current source, is considered separately.

  • Cathodic Protection of steel in concrete
    Corrosion Science, 2003
    Co-Authors: B.s. Wyatt
    Abstract:

    Abstract Cathodic Protection of reinforced concrete has been developed by a combination of trial and error, fundamental research, applied research and transfer of technology from related fields. These developments have been underway for 35 years and have been progressed by civil engineers, concrete technologists, corrosion scientists and Cathodic Protection engineers. In the past 6 years in the U.K. the investment in repairs to reinforced concrete structures incorporating Cathodic Protection has grown from a minimal £100,000 p.a. to some £20 million p.a. This paper reviews the developments in Cathodic Protection of reinforced concrete during the last 35 years with particular emphasis on developments during the last decade. The critical areas of this multi-discipline technology in respect of system performance and future development are anode systems, anode overlays and assessment of Cathodic Protection performance. These critical areas are addressed in detail and some requirements for future work are highlighted.

  • Cathodic Protection OF A ROLL-ON/ROLL-OFF FACILITY
    1990
    Co-Authors: B.s. Wyatt, A Lothian
    Abstract:

    In 1987, a Cathodic Protection system was installed on the reinforced-concrete access ramp and mooring dolphins of the ro/ro ferry facility at Dunoon, on the north side of the Clyde estuary in the UK. This article presents the owner's assessment of the engineering and economic factors that resulted in the selection of Cathodic Protection for the prevention of corrosion. Details are also given regarding the installation, commissioning and operation of the Cathodic Protection system.

Olof Forsén - One of the best experts on this subject based on the ideXlab platform.

  • Cathodic Protection of ships in brackish water
    Journal of Solid State Electrochemistry, 2006
    Co-Authors: Jari Aromaa, Antero Pehkonen, Olof Forsén
    Abstract:

    The operation of ice-going vessels depends on the condition of the hull surface. Corrosion increases the roughness of ship hull, which increases drag and fuel consumption. The hull surface smoothness is maintained by using coatings and Cathodic Protection. The cold brackish water is different from ocean water as it has lower salt content, lower conductivity, and higher concentration of dissolved oxygen. These factors mean that the design of the Cathodic Protection system for ship hulls requires different design values, such as Protection current density and protected length, than those given in Cathodic Protection standards. In this paper, we have estimated the Protection current density with polarization curves and the protected length by using Wagner number and dimension and conductivity scaling. In brackish water the Protection current density was two times that in ocean water. The protected length in brackish water varied between 10 and 15% of that in ocean water. In poorly conducting brackish water, the current capacity of a Cathodic Protection system is used mostly for overcoming the solution resistance, not for delivering Protection current.

V Ashworth - One of the best experts on this subject based on the ideXlab platform.

  • principles of Cathodic Protection
    Reference Module in Materials Science and Materials Engineering#R##N#Shreir's Corrosion, 2010
    Co-Authors: V Ashworth
    Abstract:

    Cathodic Protection is unique among all the methods of corrosion control in that, if required, it is able to stop corrosion completely, but it remains within the choice of the operator to accept a lesser, but quantifiable, level of Protection. Manifestly, it is an important and versatile technique. In principle, Cathodic Protection can be applied to all the so-called engineering metals. In practice, it is most commonly used to protect ferrous materials and predominantly carbon steel. It is possible to apply Cathodic Protection in most aqueous corrosive environments, although its use is largely restricted to natural, near-neutral environments (soils, sands, and waters, each with air access). Thus, although the general principles outlined here apply to virtually all metals in aqueous environments, it is appropriate that the emphasis, and the illustrations, relate to steel in aerated natural environments. The text seeks to show why Cathodic Protection is apparently so restricted in its scope of application despite its apparent versatility. Nevertheless, having recognized the restricted scope, it is important to emphasize that the number and criticality of the structures to which Cathodic Protection is applied is very high indeed.

  • 10.1 – Principles of Cathodic Protection
    Corrosion, 1994
    Co-Authors: V Ashworth
    Abstract:

    4.18.1 Historical Background 2747 4.18.2 Electrochemical Principles 2748 4.18.2.1 Aqueous Corrosion 2748 4.18.2.2 Cathodic Protection 2748 4.18.2.3 Oxygen Reduction 2749 4.18.2.4 Hydrogen Evolution 2750 4.18.3 Methods of Applying Cathodic Protection 2751 4.18.3.1 Impressed Current Method 2751 4.18.3.2 Sacrificial Anodes 2752 4.18.4 Proof of Protection 2753 4.18.4.1 Steel 2753 4.18.4.2 Other Metals 2755 4.18.4.3 Steel in Concrete 2755 4.18.4.4 Potential Measurements 2756 4.18.5 Current Requirements 2757 4.18.6 Coatings and Cathodic Protection 2758 4.18.7 Calcareous Deposit 2759 4.18.8 Potential Attenuation in Impressed-Current Systems 2759 4.18.9 Summary 2761 References 2762

Kazuhiro Ikawa - One of the best experts on this subject based on the ideXlab platform.

  • Cathodic Protection for prestressed concrete structures
    Construction and Building Materials, 1998
    Co-Authors: Kouji Ishii, Hiroshi Seki, Tsutomu Fukute, Kazuhiro Ikawa
    Abstract:

    Abstract Recently, corrosion of prestressing steel in concrete has been reported. One of the effective countermeasures to stop corrosion is Cathodic Protection. Cathodic Protection has been applied to reinforced concrete structures so far. However, there are several uncertainties especially associated with applicability to prestressed concrete structures. The authors conducted a series of experiments using Cathodic Protection system on prestressed concrete structures in order to establish the reliable Cathodic Protection systems. This article indicated some experimental results on susceptibility of prestressing steel to hydrogen embrittlement and mechanical behavior of pretentioned beams subjected to current supply.

  • Cathodic Protection for Protecting Prestressed Concrete
    1993
    Co-Authors: Kiyoshi Katawaki, Hiroyuki Sakamoto, Akira Ishikawa, Kazuhiro Ikawa, Satoru Yamamoto
    Abstract:

    Due to the good effect of corrosion Protection of reinforcing steel bars, even in concrete highly chloride contaminated, Cathodic Protection for concrete structure now carried out as a standard to prevent salt corrosion in severe environments. In order to develop the design of Cathodic Protection, full scale size trials were carried out on test beams of prestressed concrete. As a result, it has been recognized that the Cathodic Protection are practically easily applied and good effective for repairing concrete beam damaged by chloride corrosion. Therefore a draft manual for the Cathodic Protection of steel materials in concrete structures has been prepared on the basis of these test results. Hereafter, this manual will be used as the guideline in applying Cathodic Protection to concrete bridges.

Jari Aromaa - One of the best experts on this subject based on the ideXlab platform.

  • Cathodic Protection of ships in brackish water
    Journal of Solid State Electrochemistry, 2006
    Co-Authors: Jari Aromaa, Antero Pehkonen, Olof Forsén
    Abstract:

    The operation of ice-going vessels depends on the condition of the hull surface. Corrosion increases the roughness of ship hull, which increases drag and fuel consumption. The hull surface smoothness is maintained by using coatings and Cathodic Protection. The cold brackish water is different from ocean water as it has lower salt content, lower conductivity, and higher concentration of dissolved oxygen. These factors mean that the design of the Cathodic Protection system for ship hulls requires different design values, such as Protection current density and protected length, than those given in Cathodic Protection standards. In this paper, we have estimated the Protection current density with polarization curves and the protected length by using Wagner number and dimension and conductivity scaling. In brackish water the Protection current density was two times that in ocean water. The protected length in brackish water varied between 10 and 15% of that in ocean water. In poorly conducting brackish water, the current capacity of a Cathodic Protection system is used mostly for overcoming the solution resistance, not for delivering Protection current.