Sulfide Corrosion Cracking Research Articles

Factors in Sulfide Corrosion Cracking of High Strength Steels

Abstract Results of laboratory sulfide corrosion cracking tests on commercial steel alloys are presented. Emphasis is placed on effects of environmental factors, alloy composition and metallurgical variables. Environmental factors studied include pH in the range of 2 to 5, H2S partial pressures in the range 0.001 to 1.0 atmosphere and addition of sodium chloride. Twelve percent chromium stainless steels and low alloy steels containing more than 1 percent nickel, were found to have lower resistance to cracking at the same hardness level than low alloy steels normally used for oil field equipment. Plastic deformation of low alloy steels by cold rolling decreased the resistance to cracking.

RI利用による鉄鋼の硫化物腐食われに関する研究

It has been generally considered that sulfide corrosion cracking of steels is hydrogen embrittlement cracking, but it has not been confirmed clearly. Furthermore, few studies on the behavior of sulfer has been reported.In the present study experiments have been made on the behavior of sulfide in the sulfide corrosion cracking using a radio-isotope of 35S: 80 kg high strength steel, 60 kg high strength steel, APS steel and boiler plate steel were used as specimens. These specimens were immersed in sulfide corrosive solution under stress for a long time. After this treatment, the distributions of 35S in these specimens were investigated by radiometry and an autoradiographic technique.The experimental results are as follows:(1) The more the susceptibility of the specimens to the sulfide corrosion cracking is, the greater the amount of 35S deposit. And 35S diffuses in such specimens more deeply.(2) The distribution of induced crack corresponds almost exactly to that of 35S. Howevre, 35S cannot be detected in some cracks.(3) The influence of stress on the sulfide corrosion cracking was confirmed.(4) It is considered that sulfur diffuses into grain boundaries of steels.It has been conclude that the sulfide corrosion cracking is different from simple hydrogen embrittlement cracking and stress corrosion cracking by anode attacks exerts influence on the sulfide corrosion cracking.From the these points of view, the behavior and the role of sulfur in the sulfide corrosion cracking should be investigated with more keen interest.

軟鋼および高張力鋼の硫化物腐食割れにおよぼす予歪の影響

We discussed the susceptibility for sulfide corrosion cracking of pre-strained mild steel and high-strength steels.The tested materials were four kinds of steels (SB42B, HT50, HT60 and HT80), and the test pieces, which were circular rods, were strained by tension test at room temperature before being submitted to sulfide corrosion test. Sulfide corrosion test was carried out under constant tensile load in the solution' of 0.5% acetic acid saturated with hydrogen sulfide at the temperature of 35°C, and the time to failure was measuredIt became clear that the effect of pre-strain on the time to failure was closely associated with the structure o each steel. In the material like HT80 of which the structure was tempered martensite, the time to failure shortened with the increase of pre-strain until the test piece began local shrinkage, but conversely the time to failure lengthened with the increase of pre-strain beyond the uniform elongated zone. In the material like HT60, the time to failure shortened with the increase of pre-strain all over the zone of pre-strain. In the materials like SB42B and HT50 of which the structure was ferrite plus pearlite, the time to failure lengthened with the increase of pre-strain until the test piece began local shrinkage, but beyond this region of pre-strain the time to failure already did not practically change.The volume of the diffusible hydrogen absorbed in steel increased with the increase of pre-strain, and this relation was observed with all kinds of steels.Though it is believed that sulfide corrosion carcking is introduced by the diffusible hydrogen absorbed in steel, there is not any relation established between sulfide corrosion susceptibility and the volume of absorbed hydrogen.As far as the local shrinkaged HT80 is concerned, the failure occurred at the part separated from the center of local shrinkage.Moreover, small longitudinal cracks were observed at the core of local shrinkage for all kinds of steels. It is thought that these cracks occurred only though the diffusible hydrogen in steel.

高張力鋼の硫化物腐食割れにかかわる因子

高張力鋼の硫化物腐食割れにかかわる因子

石油精製装置内における溶接構造用高張力鋼の硫化物腐食割れの試験

Tests on sulfide corrosion cracking of weldable high strength structual steels were performed at oil refining plants. The tests were carried out on eight main parts of the oil refining plants, viz., oil storage tank, prefractionator, top and bottom sides of fractionator, stabilizer, stabilizer-receiver, depropanizer-receiver, and vacuum column. The duration of testing was about one year. The results obtained are as follows: (1) Sulfide corrosion cracking was only observed on the test specimens inserted in the stabilizer-reciver, and specimens in other processing units in the plant were found to be unaffected. It was observed that the conditions causing the sulfide corrosion cracking might be attributed to the environment being (a) liquid phase, (b) rich in H2O, (c) rich in active sulfide such as H2S, and (d) subjecting temperature. (2) Types of cracks observed on the test pieces were corrosion cracking on the surfaces, hydrogen blister, and hydrogen crack. (3) The scales removed from the cracked specimen surface were examined and as a result, kansite (Fe9S8) that is closely related to sulfide corrosion cracking was detected by X-ray diffraction. Residual hydrogen in the specimen was rich compared with that in other parts of plants. (4) The corrosion rate of tested materials varied considerably by individual cases, but did not vary to any extent by different heats of steel.

高張力鋼板の硫化物腐食割れ感受性の方向性について

高張力鋼板の硫化物腐食割れ感受性の方向性について

各種高張力鋼の硫化物腐食割れの感受性について

In recent years, the problem of sulfide corrosion cracking of weldable high-strength structural steel in the oil refining field has been regarded as important. In this experiment, using the bent-beam system, the susceptibility to sulfide corrosion cracking in each grade steel was investigated. It appeared that susceptibility to sulfide corrosion cracking was mainly related to material strength, and that the rate of crack initiation depended on the H2S concentration in a corrosion medium and the stress applied to the material. The correlation between the lower limit of H2S concentration and the lower limit of stress for crack initiation was investigated in each kind of the steel. Types of cracking observed in the specimen were corrosion cracks on the specimen surface, hydrogen blister, and hydrogen cracks.

高張力鋼の硫化物応力腐食割れの研究 (第1報)

In order to investigate the influence of the nature of corrosion products on apparent difference in the susceptibility to sulfide corrosion cracking between nickel-free and nickel-containing high strength steels, the corrosion products formed on surfaces of these steels in hydrogen sulfide aqueous solution have been compared and discussed by means of optical microscopy, X-ray diffraction and electron diffraction. The corrosion weight losses of the steels in the similar medium were also determined.The results are summarized as follows:1) The corrosion product formed on the steel surface in saturated aqueous hydrogen sulfide appears to be composed primarily of tetragonal iron sulfide and it is not kansite as so far considered.2) Nickel in these steels acceralates the crystallization of tetragonal iron sulfide formed on the steel surface.3) Nickel also increases the corrosion rate of the steels in hydrogen sulfide solution.4) The structure of corrosion products in the initial stage of corrosion reaction differs from that of nickel-containing steel to that of nickel-free steel and the difference in the structure of sulfide becomes more distinctive after aging. The particular sulfide formed on nickel-containing steel is believed to be relevant to the sulfide stress-corrosion cracking.

硫化物腐食による高張力鋼の脆化について

硫化物腐食による高張力鋼の脆化について

Sulfide Corrosion Cracking of High Strength Steels

Sulfide Corrosion Cracking of High Strength Steels

A Study on the Sulfide Corrosion Cracking of Welded High Strength Steel

A Study on the Sulfide Corrosion Cracking of Welded High Strength Steel

高張力鋼の硫化物腐食割レに関する研究の展望

高張力鋼の硫化物腐食割レに関する研究の展望

マルテンサイト系ならびにフェライト系ステンレス鋼の硫化物腐食割れについて (その1)

The effects of heat treatment on sulfide corrosion cracking of several martensitic and ferritic stainless steels were investigated. Sodium chloride solution saturated with hydrogen sulfide and containing acetic acid was adopted as corrosive medium. The results of this study may be summarized as follows:1) With 410 steel, all of the specimens austenitized at 1, 150°C, followed by an oil quenching and tempered at various temperatures in the range from 300 to 800°C were cracked in one week or less, but the appearances of the crack varied with tempering temperatures as shown in Fig. 1. Cracking was of intergranular path with respect to the former austenite when tempered in the range from 550 to 700°C for short periods of time, but changed to transgranular with increase of tempering time.2) With 430 and 7 Cr-Si-Al steels, fine cracks of limited length and blisters appeared in all of the specimens treated at 1, 150°C, followed by an oil quenching and annealed at various temperatures in the range from 300 to 800°C. Paths of crack are predominantly transgranular. But when the specimens are annealed in the range from 550 to 750°C, cracks are partly transgranular (in the ferrite grain) and partly intergranular (when encountered with former austenite grain).3) 410 steels oil-quenched at 1, 300°C and annealed at various temperatures displayed a similar trend to that found in 430 and 7 Cr-Si-Al steels.4) With 25 Cr-2.5 Ni steel, no cracking was observed during the 10 days test periods used.5) Variations of mechanical properties with time of exposure to corrosive medium are described.

Stress Corrosion Crocking of Oil Country Tubular Goods★

Abstract Stress corrosion cracking as encountered in oil production is discussed as two problems: sulfide corrosion cracking and sweet corrosion cracking. Brief review of the literature is included. A new test method is given which uses a notched ring loaded to different percentages of yield deformation. Also includes simple polished beam specimen test methods. Tabular data is given on hardness, applied stress and time-to-failure obtained in a saturated H2S-brine system using J-55 and N-80 steels. Concludes that any steel will suffer sulfide corrosion cracking above given hardness limits and that these limits depend on applied stress. Tests to reproduce failures in sweet systems are reported. Conclusion is drawn that sweet cracking failures are sulfide cracking at low H2S concentrations and that time-to-failure is an inverse function of the H2S concentration. 3.2.2

Laboratory and Field Methods for Quantitative Study Of Sulfide Corrosion Cracking

Abstract Quantitative procedures for sulfide corrosion cracking tests, both in the laboratory and in the field, have been developed. The statistical techniques of probit analysis have been adapted for use with cracking test data so as to make optimum use of a minimum number of tests. Analysis of the data from laboratory tests yields a number which is called the critical strain, Sc. This is the strain at which the probability of failure under the specific test conditions used is one-half. Very susceptible steels have low Sc values whereas non-susceptible steels have high Sc values. The critical strain is a function not only of the alloy tested but also of the test environment and procedure. It is lowered by addition of acids (especially organic acids such as acetic) and carbon dioxide. Using alloys of varying Sc values, all tested at the same high strain, the relative severity of any given test environment (e.g., flow from a sour gas well) can be measured. Analysis of the data from field tests yields a sev...

Influence of Metallurgical Variables On Resistance of Steels to Sulfide Corrosion Cracking

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation J. P. FRASER, G. G. ELDREDGE; Influence of Metallurgical Variables On Resistance of Steels to Sulfide Corrosion Cracking. CORROSION 1 November 1958; 14 (11): 44–50. doi: https://doi.org/10.5006/0010-9312-14.11.44 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest Search

The Behavior of Steels in Hydrogen Sulfide Environments★

Abstract Spontaneous cracking of steels in deep high-pressure condensate wells producing gas containing hydrogen sulfide has been a subject for considerable investigation during the past seven or eight years. This paper presents: (1) a definition and possible mechanisms for sulfide-stress cracking of steels, (2) the methods currently being used to establish the susceptibility of steels to this phenomenon, (3) a brief summation of the significant developments from research on the problem, and (4) the measures that are currently indicated to minimize the possibilities of such failures in steel equipment. The term “sulfide-stress cracking” is preferred to the commonly used “sulfide corrosion cracking” since the phenomenon is stress dependent. The susceptibility of most constructural steels to sulfide-stress cracking can be minimized, if not eliminated, by appropriate heat treatment which must include tempering at a temperature not less than 1150 F and by limiting the maximum mechanical properties to predetermined levels. When the use of high strength metals is unavoidable, certain nonferrous alloys, which thus far have indicated a high degree of insensitivity to the phenomenon, are suggested. 3.2.2

Sulfide Corrosion Cracking Of High Strength Bolting Materials

Abstract The sulfide corrosion cracking behavior of Type 4140 bolts was studied in H2S-H2O systems at temperatures of 20 to 120 C and at pressures of 1 to 17 atmospheres. The susceptibility to cracking increased with increasing bolt hardness, increasing applied stress, increasing amounts of plastic deformation, and decreasing test temperature. Other bolting materials such as Inconel, Inconel-X, K-Monel, and annealed Type 316 stainless steel were completely resistant to sulfide corrosion cracking. The use of protective metallic coatings and the addition of corrosion inhibitors to the test system were evaluated as means of preventing the sulfide corrosion cracking of Type 4140 bolts. The sulfide corrosion cracking of Type 4140 bolts is believed to be best explained on the basis of hydrogen embrittlement. 3.2.2