Corrosion design considerations

Proper Design Design considerations with respect to minimizing corrosion dirliculties should include the desirability for free and... 

The implications of the terms predictable and unpredictable used in the context of corrosion require further consideration, since they are clearly dependent on the knowledge and expertise of the engineer, designer or corrosion designer who takes the decision on the metal or alloy to be used, or the procedure to be adopted, to control corrosion in a specific environmental situation. On this basis a corrosion failure (i.e. failure of the function of the metal due to corrosion within a period that is significantly less than the anticipated life of the structure) may be the result of one or more of the following possibilities ... 

A wide variety of protective coating types and systems is available for corrosion control on external and internal surfaces of structural and process plant in marine and offshore engineering. These are discussed in detail elsewhere in this text, and the purpose here is to highlight the critical importance of certain design and related operational aspects which affect both the selection and performance of protective coating systems. The following design considerations should be made ... 

Concrete exposed to deicer salts, or to a marine environment is subjected to chloride and sodium loading. The ability of concrete to resist the penetration of chlorides and sodium is a primary design consideration in marine or cold environments. The ingress of chlorides into concrete is a major problem due to chloride-induced corrosion of the reinforcing steel and deicer salt scaling [a process by which a thin layer (< 1 mm) of concrete deteriorates from the surface of the concrete]. The penetration of sodium from sea water or deicer salts is generally... 

Moisture and corrosives content are the major gas stream characteristics requiring design consideration. Standard fabric filters can be used in pressure or vacuum service, but only within the range of about 640 mm of water column (25 inches of water column). Well-designed and operated baghouses have... 

In addition to the active design principles for reducing the risk of sulfide problems, a number of more passive principles exist. The following design considerations are especially relevant for the reduction of corrosion selection of corrosion-resistant materials and design of a well-ventilated sewer system. 

Design Considerations in Seawater Corrosion Protecting System... 

Seawater as mentioned earlier is mostly the process cooling fluid for coastal based power plants. The main design considerations for selection of corrosion protection measures for seawater-based process cooling systems are ... 

NACE Standard RP 0187, Design considerations for corrosion control of reinforcing steel in concrete, NACE Int., Houston, Texas, 2000. 

Corrosion protection considerations should address not only basic material choices and protective coatings but also design details such as avoidance of crevices, and use of electrically insulated connections where required. Special protection should be given where process wastes may build up, say at column bases, where suitable plinths are usually needed. 

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