Abstract h 2 s gas in the crude oil or natural gas causes hydrogen degradation such as hydrogen induced cracking hic and sulfide stress cracking ssc. Particularly common to the oil and gas industry where the use of steel. Corrosion testing in co2 and h2s environments in the oil and gas industry, materials are often exposed to extreme high pressure and temperature conditions and aggressive environments containing chlorides, carbon dioxide co2, hydrogen sulfide h2s and strong acids. High partial pressure h2s pipelines pipelines, piping and. Hic in welding cold cracking haz cracking moisture n org compounds r primary sources of h. Pdf the effect of the partial pressure of h2s and co2 on the. Hydrogen induced crack resistant hic steel plate brown mcfarlane offers the widest range of carbon and stainless steel plate, available exstock. Effects of h2s partial pressure and ph of test solution on the hydrogen induced cracking of linepipe steels wan keun kim, seong ung koh, kyoo young kim, boo young yang, ki bong kang dept. Hydrogen induced cracking hic is a failure mechanism resulting in sudden exposures and cracks due to growing laminations inside the base material and welds. Hydrogen induced cracking tests were conducted on high strength steels and nickeliron base alloys using the constant displacement boltloaded compact specimen. H ydrogen induced cracking hic is a far too common type of failure. The symbol for pressure is usually p or p which may use a subscript to identify the pressure, and gas species are also referred to by subscript. Corrosion and hydrogeninduced cracking of pipeline steel in.
The electrochemical and sulfide stress corrosion cracking sscc behaviors of cr stainless steel and p110 steel were investigated in a simulated acidic annular environment with lowtemperature and highpressure h2sco2 using electrochemical methods, ubend. It involves atomic hydrogen, which is the smallest atom, that diffuses into a metallic structure. Naceastm g193 1 includes the following description of hydrogen blistering. Sulfide stress cracking an overview sciencedirect topics. Introduction hic is a kind of the hydrogen embrittlement which occurs in the form of surface blisters andor internal cracks in the absence of applied stress. The rate of x60 was slightly higher than that of x52 steel. Nayef ma, abdullah aa 2019 the effect of the partial pressure of h 2 s and c o 2 on the permeation of hydrogen in carbon steel by using pressure buildup techniques. Factors influencing hydrogen induced cracking welding answers. Hydrogen assisted cracking and co2 corrosion behaviors of lowalloy steel with high strength used for armor layer of flexible pipe. Corrosion and stress corrosion cracking scc tests were performed on the cylinder. Factors influencing hydrogen induced cracking welding.
Pdf the effect of the partial pressure of h2s and co2 on. Hydrogen induced cracking hic on steel for corrosion. Sep 07, 2009 the methane molecules create a pressure which leads to embrittlement and even cracking of the metal. Hydrogen induced cracking hic occurs when carbon steel is exposed to hydrogen sulphide h 2 s and is the direct result of electrochemical corrosion reactions between the sour service or wet h 2 s environment. Incoloy 825 is superiorly immune to stainless steel grade 316 in the chloride media due to larger content of nickel.
Hydrogeninduced cracking an overview sciencedirect topics. The electrochemical behaviour of two carbon steels exposed to the acidic solutions and their resistance to hydrogen induced cracking hic is evaluated in order to determine the effect of hydrogen damage on the failure process of the steels used in line pipe and casing at a geothermal plant. Over time, the metal becomes so brittle that it cracks. Influence of hydrogen sulfide on co2 corrosion in pipeline steel. Hydrogen induced cracking hic is a common form of wet h2s cracking caused by the blistering of a metal due to a high concentration of hydrogen. Influence of h2s partial pressure on the corrosion. Daltons law expresses the fact that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual gases in the mixture. Evaluation of the effects of natural gas contaminants on. In the solution containing high pressure co2, cr, and p110 steels exhibited general.
In presence of small amount of h2s, the metal usually fails due to sulfide stress cracking ssc, which is a special type of hydrogeninduced cracking hic. Effects of h 2 s partial pressure and ph of test solution on the hydrogen induced cracking of linepipe steels authors wan keun kim dept. When metal is subjected to tensile stress with high level of hydrogen content, hydrogen induced cracking occurs. H2s, co2, sour service, hydrogen embrittlement, sulfide stress cracking, hydrogen induced cracking, high strength steels overview for the first phase of the project solution has been developed to overcome sulfide stress corrosion problems in high strength steel. However, the test environment of nace tm028496 standard hic test method is unnecessarily severe than that of actual sour service conditions. With three point bend specimens the typical appearance of the sohictype fractures could be reproduced experimentally. Stress corrosion cracking scc of nickelbased alloys. Effect of pressure on wet h2s co2 corrosion of pipeline. A second problem which sour service can cause in rolled steels, namely hydrogen pressure induced cracking otherwise variously known as hydrogeninduced cracking hic, stepwise cracking swc, blister cracking, and by other termshpic, has also been shown to be dependent on hydrogen concentration within the steel, with different steels. Unstressed test specimens are exposed to a solution at temperature of. In addition to ph and h2s partial pressure, test duration is another.
It is a complex process that is not completely understood because of the variety and complexity of mechanisms that can lead to embrittlement. The boltloaded specimen was subjected to both acid and electrochemical cell environments in order to produce hydrogen. Cosasco provides hydrogen monitoring solutions for corrosion control such as hydrogen blistering hydrogen induced cracking hic on steel. Stress corrosion cracking behavior of nickel base alloys.
This equality arises from the fact that in an ideal gas the molecules are so far apart that they do not interact with each other. The usual physical chemistry of calcocarbonic equilibria is also presented in a new form which better emphasizes the influence of the partial pressure of co 2 as the. Corrosion testing in co2 and h2s environments lbbc. The results show that the corrosion rate of the two steels increased with the h2s and co2 partial pressure at the temperature of 60oc with a constant h2s co2 partial pressure ratio of 1. The electrochemical and sulfide stress corrosion cracking sscc behaviors of cr stainless steel and p110 steel were investigated in a simulated acidic annular environment with lowtemperature and highpressure h2sco2 using electrochemical methods, ubend immersion tests, and scanning electron microscopy. Effect of h2s partial pressure on stress corrosion cracking. Material selection for sour service environment pipeline. Aug 02, 2014 the entrapped hydrogen makes cavities in metal that results in cracking due to weak ductility and tensile strength. In order to determine the acidity of corrosive media prevailing in oil and gas wells where co 2 corrosion is encountered, a ph meter has been built which enables ph measurements under pressures from 0. The effect of the partial pressure of h2s and co2 on the permeation of hydrogen in carbon steel by using pressure buildup techniques article pdf available in corrosion houston tx august. Hydrogen embrittlement he also known as hydrogen assisted cracking hac and hydrogeninduced cracking hic, describes the embrittling of metal after being exposed to hydrogen. Also high strength structural steels which are welded are exposed to a certain hydrogen pickup which means a risk at fracture and blistering due to hic. Influence of hydrogen sulfide on co2 corrosion in pipeline. Corrosion and hydrogeninduced cracking of pipeline steel in moist triethylene glycol diluted with liquid hydrogen sulfide.
This is a type of deterioration which can be linked to corrosion and corrosioncontrol processes. Hic usually occurs due to the effects of aqueous hydrogen charging of steel in wet h2s refinery process environments. The effect of different partial pressures of h 2 s p h 2 s on the hydrogen permeation behaviour of apix52 pipeline carbon steel was investigated in a hightemperature and highpressure hydrogen permeation device. Hydrogen induced cracking tests of high strength steels. The effect of the partial pressure of h2s on the permeation of hydrogen in low carbon pipeline steel. Hydrogen induced cracking is a mechanical fracture caused by penetration and diffusion of atomic hydrogen into the internal structure of steel, which changes into molecular. The effect of the partial pressure of h2s on the permeation. The results showed that the peak value of the hydrogen permeation curves, the corrosion rates, the susceptibility to hydrogen induced cracking and the amount of diffusible hydrogen. Effect of pressure on wet h2s co2 corrosion of pipeline steel.
Effects of h2s partial pressure and ph of test solution on the hydrogen induced cracking of linepipe steels wan keun kim, seong ung koh, kyoo young kim, boo young yang, ki bong kang. High temperatures, large chloride content and partial pressure of h2s and small ph make the. However, the test environment of nace tm028496 standard hic. Effect of h2s partial pressure on stress corrosion cracking behavior of cr stainless steel in annulus environment around co2 injection well. Unstressed test specimens are exposed to a solution at temperature of 25deg cent with continuous h2s gas flow.
The ssc of medium strength steels has been a continuing source of trouble in the oil fields, and from these troubles has evolved in international standards 6. The effects of sulfide stress cracking on the mechanical properties. Processes or conditions involving wet hydrogen sulfide, i. What is the minimum partial pressure of h2s that requires.
Co2 partial pressure 5 to 20 psia most fields in this group used inhibitor batch treatment since startup. Preventing hydrogen induced cracking welding answers. For corrosion resistant alloys cras there is now pph 2 s low limit, which means precautions need to be taken whenever the possibility of h 2 s is present. Corrosionpedia what is hydrogeninduced cracking hic. Environmental cracking of stainless and nibase alloys hydrogen sulfide corrosion acidic environments hzs as well as co2 can be dissolved in aqueous environments to form acidic, corrosive solutions. The terms stepwise cracking, hydrogen pressure cracking, blister cracking o hydrogen induced stepwise cracking have been used in the past to describe cracking of this type, but are now considered. Materials in the sour environment are susceptible to sulfide stress corrosion cracking ssc and hydrogen induced cracking, hydrogen embrittlement and exfoliation hehic that leads to various modes of failure including stepwise cracking, hence the importance during the design stage on material selection. High partial pressure h2s pipelines drillernic petroleum 15 apr 05 05. The hydrogen induced cracking hic susceptibility of line pipe steel is affected by the hydrogen permeation rate.
Cracking is sometimes accompanied by surface blistering. High partial pressure h2s pipelines pipelines, piping. When combined these subscripts are applied recursively. Abstract a mathematical model was proposed for determining the crack growth rate of hydrogen induced cracking hic in steel plates exposed to a sour gas. Jun 03, 2018 hydrogeninduced cracking hic refers to the internal cracks brought about by material trapped in budding hydrogen atoms. H 2 s gas in the crude oil or natural gas causes hydrogen degradation such as hydrogen induced cracking hic and sulfide stress cracking ssc. H2s partial pressure, 1 mpa and co2 partial pressure. Cracking occurs due to a significant loss in ductility. Hydrogeninduced cracking hic in steel is a risk problem when steels are charged with hydrogen in service as in various hydrogen sulfide environments like sour oil and gas wells and some power plants. Effects of h2s partial pressure and ph of test solution on. Hydrogeninduced cracking also referred to as cold cracking, is caused by the diffusion of hydrogen in the crystal lattice of haz near the fusion boundary. The co2 partial pressure had no significant effect. The hydrogen deleterious effect has a relevant industrial and economic impact being, at the same time, a challenge from the scientific point of view. High temperature hydrogen attack htha is an insidious condition that can occur in process equipment exposed to hydrogen at elevated temperatures at least 400f or 204c, under dry conditions, when hydrogen disassociates into nascent atomic hydrogen, which is then driven into the steel by the temperature and pressure of the environment.
May 19, 2009 susceptibility to hydrogen blistering and hydrogen induced cracking can be apportioned to the quality of the steel plate used. O ur last post factors influencing hydrogen induced cracking went over the factors that contribute to hydrogeninduced cracking. It is also called hydrogen assisted cracking hac and delayed cracking since it does not occur right after welding, but a few hours or days after the weld has completely cooled down to ambient temperature. Hydrogeninduced cracking hic refers to the internal cracks brought about by material trapped in budding hydrogen atoms. The effect of the partial pressure of h2s and co2 on the permeation of. Hydrogeninduced crack growth rate in steel plates exposed. Hydrogen cracking its causes, costs and future occurrence. The formation of subsurface planar cavities, called hydrogen blisters, in a metal. Electrochemical and sulfide stress corrosion cracking. Hydrogen cracking is also named as toe cracking or underbead cracking due to its location of occurrence. The terms stepwise cracking, hydrogen pressure cracking, blister cracking o hydrogeninduced stepwise cracking have been used in the past to describe cracking of this type, but are now considered.
Jul, 20 the presence of electronegative species known to poison hydrogenation recombination reactions on transition metals drastically increases the adsorbed atomic hydrogen uptake. The electrochemical and sulfide stress corrosion cracking sscc behaviors of cr stainless steel and p110 steel were investigated in a simulated acidic annular environment with lowtemperature and high pressure h2s co2 using electrochemical methods, ubend immersion tests, and scanning electron microscopy. Effect of h2s partial pressure on stress corrosion. In the gas phase, a stream is sour if the h2s partial pressure exceeds 0. Hydrogen induced cracking steel features, applications. Blast furnaces give off many unpleasant and unhealthy gases. Another type of hydrogen corrosion, stressorientated hydrogen induced cracking sochic, is normally found in the base metal adjacent to the weld, where the stress point is highest due to the internal pressure of the. A second problem which sour service can cause in rolled steels, namely hydrogen pressure induced cracking otherwise variously known as hydrogen induced cracking hic, stepwise cracking swc, blister cracking, and by other termshpic, has also been shown to be dependent on hydrogen concentration within the steel, with different steels. Hic testing is recommended to evaluate the resistance of pipeline and pressure vessel plate steels to hydrogen induced cracking corrosion caused by hydrogen absorption from aqueous sulfide corrosion. Hydrogeninduced cracking hic is a far too common type of failure. In the solution containing high pressure co2, cr, and p110 steels. The effect of different partial pressures of h 2 s p h 2 s on the hydrogen permeation behaviour of apix52 pipeline carbon steel was investigated in a hightemperature and high pressure hydrogen permeation device. This process is known as hydrogen embrittlement or hydrogeninduced cracking. Corrosion and hydrogeninduced cracking of pipeline steel.
Hydrogen embrittlement he also known as hydrogen assisted cracking hac and hydrogen induced cracking hic, describes the embrittling of metal after being exposed to hydrogen. The results show that the corrosion rate of the two steels increased with the h2s and co2 partial pressure at the temperature of 60oc with a constant h2sco2 partial pressure ratio of 1. The methane molecules create a pressure which leads to embrittlement and even cracking of the metal. Hydrogeninduced crack growth rate in steel plates exposed to sour environments.
Effects of h2s partial pressure and ph of test solution on the. In presence of small amount of h2s, the metal usually fails due to sulfide stress cracking ssc, which is a special type of hydrogen induced cracking hic. Furthermore, the risk of hydrogen induced cracking is present even at partial pressure of h 2 s pph2s below 0. Corrosion and hydrogen induced cracking of pipeline steel 1075 this mechanism accounts for the fact that one essential condition for this type of corrosion is direct contact of ss with the metal. The selection of the testing environments for material evaluation or inhibitor performance depends entirely upon the intended. Equivalently, low temperature hydrogen induced cracking was also noticed in inconel 718. High temperature hydrogen attack htha inspectioneering. Hydrogeninduced crack growth rate in steel plates exposed to. Many environmental factors, such as the partial pressure of h 2 s and co 2, temperature, cations, and the solution ph, affect the hydrogen permeation rate. If you recall, we mentioned you need all three factors to be present in order to have hic. The effect of different partial pressures of h2s ph2sph2s on the hydrogen permeation behaviour of apix52 pipeline carbon steel was investigated in a hightemperature and highpressure hydrogen. Hydrogen cracking its causes, costs and future occurrence p h m hart weld metal hydrogen cracking in pipeline girth welds, proc. The data have been collated and presented on one diagram, and the appropriateness of setting relaxed hardness controls for mildly sour environmental conditions has been discussed. Effect of environmental factors on hydrogen permeation in.
This clustering produces pressure in the metal which results in the metal losing ductility, toughness and tensile strength. Hydrogen induced cracking hic testing of low alloy steel in sour. Co2 partial pressure under 2 psia no corrosion protection is used with no evidence of downhole corrosion. Hydrogen induced cracking hic in the oil and gas industry. Effect of co2 partial pressure on the corrosion in flow. Hydrogen induced cracking steel features, applications and. Hydrogen induced cracking hic begins with the appearance of the hydrogen blistering on the specimen surface, and cracks generated by the hydrogen blistering gradually extend inward from the surface along the grain boundary, diffuse inside the specimen gradually, and finally form hydrogen induced cracking. Materials in the sour environment are susceptible to sulfide stress corrosion cracking ssc and hydrogeninduced cracking, hydrogen embrittlement and exfoliation hehic that leads to various modes of failure including stepwise cracking, hence the importance during the design stage on material selection. Both sulphide stress corrosion cracking sscc and hydrogen pressure induced cracking hpic have been considered. Another condition is the presence of water compare results in fig. Pdf the effect of co2 on the permeation of hydrogen in carbon.
In addition, hydrogen blistering and hydrogeninduced crack were observed in the x60 steel. Corrosion failures have occurred in unprotected wells and there is some evidence of corrosion despite regular nhibitor treatment. Hic test, hydrogen induced cracking test, step wise. Influence of h2s partial pressure on the corrosion behavior. We will now go over how to prevent hic from happening. H2s, co2, sour service, hydrogen embrittlement, sulfide stress cracking, hydrogen induced cracking, high strength steels overview for the first phase of the project solution has been developed to overcome sulfide stress corrosion problems in high strength steel armors in h2s co2 containing environment. The blistering damage tends to form parallel to the surface and to the direction of hoop stress. All you need to know is these two equations, that stem from one single idea, this idea is called the kinetic theory of gases it assumes that. For hydrogen induced cracking to take place, individual hydrogen atoms must cluster at the surface of the metal to create hydrogen molecules.
Bai p, zheng s, chen c 2015 electrochemical characteristics of the early corrosion stages of api x52 steel. Hic test, hydrogen induced cracking test, step wise cracking. Hydrogen induced cracking of hard materials zthe refining industry has had very few cases of hydrogen related cracking in pure hydrogen service. The effect of the partial pressure of h2s and co2 on the. It involves the ingress of hydrogen into a component, an event that can seriously reduce the ductility and loadbearing capacity, cause cracking and catastrophic brittle failures at stresses below the yield stress of susceptible materials. Effects of high h2s partial pressure on corrosion of apix52 and x60 pipeline steels were discussed.
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