Internal stress-corrosion cracking by aqueous solutions of CO and CO/sub 2/

Conference · Mon Jan 01 04:00:00 EST 1979

OSTI ID:6698176

Berry, W E; Payer, J H

Battelle Columbus Laboratories study of stress-corrosion cracking (SCC) of line-pipe steel in aqueous solutions of CO and CO/sub 2/ revealed that pipeline steels are susceptible to SCC at partial pressures of CO/sub 2/ and CO as low as 1 psi (6.9 kPa). For SCC to occur, carbon dioxide, carbon monoxide, and water must be simultaneously present. The SCC morphology involves multiple, transgranular cracks perpendicular to the direction of maximum tensile stresses in the steel. The surest method for control of CO-CO/sub 2/ SCC is to prevent condensation by controlling the gas composition and keeping the temperature above the dewpoint. Adequate dehydration of the gas prior to injection in the pipeline will prevent SCC, even for gas compositions that would promote severe SCC in the presence of water. The removal of CO/sub 2/ and CO does not appear to be practical because of the low levels of these gases that will still support SCC. In current industry practice, carbon dioxide levels are controlled to 10 psi (69 kPa) or less for control of general corrosion and pitting; however, no limits on CO have been established. In the presence of water, small amounts of CO can promote SCC at CO/sub 2/ concentrations that are acceptable for general-corrosion considerations. Oxygen in the gas greatly increases the severity of SCC and should be avoided.

• OSTI ID: 6698176
• Report Number(s): CONF-7910293-
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
032000* -- Natural Gas-- Transport
Handling
& Storage
36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
AQUEOUS SOLUTIONS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
CONTROL
CORROSION
CORROSIVE EFFECTS
CRACKS
DISPERSIONS
ELEMENTS
ENERGY SOURCES
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
IRON ALLOYS
IRON BASE ALLOYS
LOW PRESSURE
MIXTURES
NATURAL GAS
NONMETALS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PARTIAL PRESSURE
PIPELINES
PIPES
SOLUTIONS
STEELS
STRESS CORROSION
TEMPERATURE CONTROL