The document discusses the importance of corrosion prevention at the design stage, emphasizing that good design is as cost-effective as a poor one, yet a bad design leads to higher long-term expenses. It outlines several factors influencing equipment service life, including environmental conditions and design flaws, such as inadequate protective systems and poor fabrication. The conclusion suggests that adhering to specific design rules can help minimize issues like crevice corrosion and improve overall component longevity.

1. Corrosion
Engineering
Assist.Lecture Amjed AL-khateeb

2. Report of
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3. Introduction
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4. As an old adage says, corrosion prevention must
start at the blackboard, at the design stage. A good
design at the blackboard is no more costly than a
bad design, a bad design is always more expensive
than a good design in reality. Technical design inclu-
des the aspects of design that directly bear on the
proper technical functioning of the product attributes
that describe how it works and how it is made.
Design configuration has a critical role to play in the
service life of components.
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5. The following factors influence the service life of equipment
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6. Environmental factors affecting service life of equipment
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7. Causes of Failures in the Context of Design
1) Breakdown of protective system. Many protective surf -
ace treatments, such as coating and welding, may not be
very effective because of the presence of surface
irregularities, voids, surface porosity, undercuts, and general
surface roughness.
2) Poor fabrication. Factors, such as improper welding,
excessive cold working and excess machining lead to
failure.
3) Lack of accessibility. In complex systems, machinery,
and components, there might be inaccessible areas due to
lack of design insight where it may not be possible to carry
out the corrosion protection measures.
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8. 4) Structural heterogeneity in materials. Joining similar
materials with structural differences, such as differences in
thermo-mechanical processing, grain size, number of
impurity elements, grain boundary segregates, may cause
deviation from the performance expected.
5) Operating conditions. Factors, such as temperature,
pressure, and velocity, influence the service life if allowed
to exceed the prescribed limits.
Causes of Failures in the Context of Design
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9. Design rules
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10. Design rules
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A few designs to minimize
crevice corrosion
Larger radius is preferred for higher velocities in
order to avoid erosion–corrosion

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14. CONCLUSIONS
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Reference :-
Corrosion engineering by Mars G. Fontana
Corrosion engineering principles and practice Mc Graw Hill

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