|
 There
are over 528,000 km (328,000 mi) of natural gas transmission and
gathering pipelines, 119,000 km (74,000 mi) of crude oil transmission
and gathering pipelines, and 132,000 km (82,000 mi) of hazardous
liquid transmission pipelines. For all natural gas pipeline companies,
the total investment in 1998 was $63.1 billion, from which total
revenue of $13.6 billion was generated. For liquid pipeline companies,
the investment was $30.2 billion, from which revenue of $6.9 billion
was generated. At an estimated replacement cost of $643,800 per
km ($1,117,000 per mi), the asset replacement value of the transmission
pipeline system in the United States is $541 billion; therefore
a significant investment is at risk with corrosion being the primary
factor in controlling the life of the asset. The average annual
corrosion-related cost is estimated at $7.0 billion, which can
be divided into the cost of capital (38 percent), operation and
maintenance (52 percent), and failures (10 percent).
|
|
|
Significant maintenance costs for pipeline operation
is associated with corrosion control and integrity management.
The driving force for maintenance expenditures is to preserve
the asset of the pipeline and to ensure safe operation without
failures that may jeopardize public safety, result in product
loss, or cause property and environmental damage. A recent survey
of major pipeline companies indicated that the primary loss of
cathodic protection was due to the following two reasons: (1)
coating deterioration (30 percent) and (2) inadequate cathodic
protection current (20 percent). The majority of general maintenance
is associated with monitoring and repairing problems, whereas
integrity management focuses on condition assessment, corrosion
mitigation, life assessment, and risk modeling. With a range of
corrosion operation and maintenance cost of $3,100 to $6,200 per
km ($5,000 to $10,000 per mi), the total corrosion operation and
maintenance cost ranges from $2.42 billion to $4.84 billion.
Click
here to download the whole description of this sector
|
