【Corrosion Technology Edition】Daily Question 20170805: What is hydrogen-induced cracking?
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Also known as induced cracks, they occur when steel is operated in an environment of high temperature and high pressure hydrogen; hydrogen diffuses into the steel. During the cooling process, since hydrogen does not have time to escape from the steel, a certain amount of hydrogen remains inside it, which leads to the formation of cracks.
In acidic environments containing hydrogen sulfide, cracks that occur as a result of hydrogen generated by corrosion penetrating into the steel are known as hydrogen-induced cracking (HIC)
Hydrogen sulfide is one of the most corrosive harmful substances in oil and gas; during natural gas transportation, it plays a significant role in causing stress corrosion in the pipelines. When used in a wet hydrogen sulfide environment, hydrogen sulfide can cause hydrogen blistering (HB), hydrogen-induced cracking (HIC), and stress-oriented hydrogen-induced cracking (SOHIC) within carbon steel.
Hydrogen-induced cracks, also known as induced cracks, occur when steel is exposed to high-temperature and high-pressure hydrogen environments; hydrogen diffuses into the steel. During the cooling process, since hydrogen does not have time to escape from the steel, a certain amount of hydrogen remains within it, leading to the formation of cracks.
Hydrogen penetrates into the steel and accumulates locally, causing step-like cracking in the rolling direction of the steel, a phenomenon known as hydrogen-induced cracking.
In acidic environments containing hydrogen sulfide, cracks that occur as a result of hydrogen generated by corrosion penetrating into the steel are known as hydrogen-induced cracking
When operating in hydrogen at high temperature and pressure, hydrogen diffuses into the steel. During the cooling process after shutting down the reactor, if the cooling rate is too fast, hydrogen does not have enough time to escape from the steel, resulting in a certain amount of hydrogen remaining trapped within it. This leads to a significant loss of tensile ductility, which in turn can cause cracks to form.
In acidic environments containing hydrogen sulfide, cracks that occur as a result of hydrogen generated by corrosion penetrating into the steel are known as hydrogen-induced cracking
Hydrogen penetrates into the steel and accumulates locally, causing step-like cracking in the rolling direction of the steel, a phenomenon known as hydrogen-induced cracking.
Cracks resulting from hydrogen intrusion into the steel due to corrosion in acidic environments containing hydrogen sulfide