Wet H2S Corrosion (hydrogen sulphide) is commonly found in the Oil Refinery and Gas Production Industries and is a deterioration process which can have a major impact, particularly in the use of pressure vessel steel plate. Since any damage takes place on the interior, detection can only be observed using complicated inspection methods.
As a consequence, a failure from such hydrogen induced cracking can occur without prior warning and represents a considerable hazard which in extreme cases can result in serious injury to operatives or even death.
Also known as ‘sour service’, issues including hydrogen blistering, hydrogen induced cracking (HIC) and stress orientated hydrogen induced cracking (SOHIC) are caused by the aqueous hydrogen charging of the steel. This charging can cause blistering and embrittlement, which is potentially disastrous in carbon steel pressure vessel environments. These conditions can be present wherever there is a wet H2s environment.
There are two primary attacks on carbon steel plate in a wet H2S corrosion scenario…
The levels of corrosion in steel plate in this scenario are dictated by numerous factors including the quality of the steel itself, the chemical composition of the material, and conditions, processing and treatments applied at the mill. The suitability of the steel plate for this purpose should be established from the test certificate at the completion of production.
The provision of HIC tested carbon steel plate is a major consideration for steel procurement in the oil and gas industry as it offers high resistance against the ongoing effects of hydrogen induced cracking (HIC).