Distributed magnesium anode systems should be considered when a limited area of the pipeline needs to be protected. The system can be either a forced current system. The magnesium anode system can also be sacrificed. This system is usually used for bare-eared segments in dense areas or for reverse painted lines. In this area, the current shielding effect makes the remote bed magnesium anode system unable to provide effective protection.

The distributed magnesium anode or near-magnesium anode system provides protection on the principle that the length of the wire protected by a single near-magnesium anode depends on the change of the potential around the line, rather than the change of the potential of the line to the ground. The potential change of the plate (the length of the pipe that a single magnesium anode can protect) depends on the voltage applied to the magnesium anode. Instead of the current A out of the magnesium anode.

When distributed flexible magnesium anodes are used to protect a section of line in accordance with ground potential variation methods, the magnesium anodes must be installed together. In contrast to the forced current condition of the magnesium anode, sacrificing the magnesium anode with a large spacing is ineffective because the sacrificial magnesium anode voltage depends on the magnesium anode material, i.e., zinc or magnesium. Placing sacrificial magnesium anodes in a single hot spot (using the method described in Chapter 5) is one form of a distributed magnesium anode system. This distributed magnesium anode system can be used to effectively protect bare pigeon lines or lines that occasionally produce random leaks.

Over the past 25 years, the use of cathodic protection systems has become a standard engineering method. This system, though, is perfectly applicable in most cases. But it doesn't work in every case. This section discusses issues to be considered in the design of deep well magnesium anode systems, which can be used to guide the design and installation of deep well magnesium anode systems. Local regulations may limit the installation of deep well magnesium anode systems of certain structures, so it is necessary to communicate with local authorities plus a to obtain more information.

The magnesium anode system is a forced current cathodic protection installation. In this system, magnesium anodes are placed in specialized or existing boreholes that extend vertically down from the surface. A remote dish wholly or partially located in electricity. This has the same effect as the shallow buried beds with magnesium anodes in the far side of the structure described earlier in this chapter.