Erosion corrosion factors controlling

This chapter deals with the essential factors in the selection of systems and equipment during the design stage principles of controls, noise-reduction systems, and problems such as erosion, corrosion, maintenance and equipment cleaning, etc. 

The geometry of the system is a further factor that enables control to be effected, and in general, reducing the velocity of the solution and ensuring that flow is laminar and not turbulent will reduce the tendency for attack by erosion-corrosion. Thus the pipe diameter should be as large as possible, consistent with other considerations bends should have a large radius and inlet and outlets should be streamlined so that there is not a sudden change in section. 

Fig. 1.96 Summary of factors controlling the erosion corrosion of steels in water...

Corrosion, erosion, mechanical fatigue, operation at design limit and/or beyond it, calibration failure, design fault (such as wrong material selection), obsolescence, etc. are major contributing factors for degradation of equipment/system, and/or electrical control and instmmentation (EC I) items. 

The control of corrosion and erosion of slurry pipelines is covered by Chapter VIII of the ASME Code B31.11. The code correctly points out that in certain cases erosion is an accelerating factor in the internal corrosion of pipelines, by effectively removing scales, oxides, films, and lining. 

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