2
Fundamentals of Corrosion
labor and material, to maintain equipment and structures to prevent corrosion from taking place or to control the rate of corrosion. Falling into this
category are such items as painting, application of protective coatings or linings, operating costs for cathodically protected pipelines and structures, and
routine inspections or testing of equipment by online corrosion monitoring
instruments.
Economic losses are experienced industrially and domestically. Illustrative
of domestic losses are replacement of home hot water heaters, rusting of automobile bodies and parts (e.g., mufflers), and failure of domestic water pipes
and other miscellaneous items.
Other examples of direct losses include the additional costs incurred by
the use of corrosion-resistant metals or alloys instead of less-expensive carbon steel (when carbon steel has adequate mechanical properties but insufficient corrosion resistance), by the application of corrosion-resistant coatings
to carbon steel, or by the addition of corrosion inhibitors to water.
1.2 Indirect Losses
Although the causes of indirect losses can be listed, it would be extremely difficult — if not impossible — to place an actual cost on these losses. However,
it would be safe to assume that these costs would be some multiple of the
direct losses. Typical of these indirect losses are the following examples.
1.2.1 Shutdown
Unplanned shutdowns because of the failure of equipment resulting from
corrosion lead to loss of production and consequently loss of profit. Although
the actual cost of maintenance work may be minimal, the value of the lost
production can be considerable. If this type of occurrence is frequent, the
cost is usually added to the cost of the product.
1.2.2 Contamination
During the corrosion of a metal, the fluid being transported, stored, processed, or packaged in a metallic component can pick up metallic salts.
This metallic pick-up can be detrimental to the product; with soap products a shortened shelf life, with dyes a color alteration, and in some cases
of intermediate products the inability to carry out succeeding process
steps. For many years, lead pipes were used to transport water until it
was determined that the lead pick-up in the water caused lead poisoning
in humans.
Fundamentals of Corrosion
labor and material, to maintain equipment and structures to prevent corrosion from taking place or to control the rate of corrosion. Falling into this
category are such items as painting, application of protective coatings or linings, operating costs for cathodically protected pipelines and structures, and
routine inspections or testing of equipment by online corrosion monitoring
instruments.
Economic losses are experienced industrially and domestically. Illustrative
of domestic losses are replacement of home hot water heaters, rusting of automobile bodies and parts (e.g., mufflers), and failure of domestic water pipes
and other miscellaneous items.
Other examples of direct losses include the additional costs incurred by
the use of corrosion-resistant metals or alloys instead of less-expensive carbon steel (when carbon steel has adequate mechanical properties but insufficient corrosion resistance), by the application of corrosion-resistant coatings
to carbon steel, or by the addition of corrosion inhibitors to water.
1.2 Indirect Losses
Although the causes of indirect losses can be listed, it would be extremely difficult — if not impossible — to place an actual cost on these losses. However,
it would be safe to assume that these costs would be some multiple of the
direct losses. Typical of these indirect losses are the following examples.
1.2.1 Shutdown
Unplanned shutdowns because of the failure of equipment resulting from
corrosion lead to loss of production and consequently loss of profit. Although
the actual cost of maintenance work may be minimal, the value of the lost
production can be considerable. If this type of occurrence is frequent, the
cost is usually added to the cost of the product.
1.2.2 Contamination
During the corrosion of a metal, the fluid being transported, stored, processed, or packaged in a metallic component can pick up metallic salts.
This metallic pick-up can be detrimental to the product; with soap products a shortened shelf life, with dyes a color alteration, and in some cases
of intermediate products the inability to carry out succeeding process
steps. For many years, lead pipes were used to transport water until it
was determined that the lead pick-up in the water caused lead poisoning
in humans.