Effect of interaction between corrosion film and H2S/CO2 partial pressure ratio on the hydrogen permeation in X80 pipeline steel

2020 ◽  
Vol 55 (5) ◽  
pp. 392-399
Author(s):  
Chengshuang Zhou ◽  
Bei Fang ◽  
Jing Wang ◽  
Shiyin Hu ◽  
Baoguo Ye ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Hydrogen Permeation ◽  
Pipeline Steel ◽  
Pressure Ratio ◽  
X80 Pipeline Steel ◽  
Co2 Partial Pressure ◽  
Corrosion Film ◽  
Partial Pressure Ratio

Effect of H 2 S/CO 2 partial pressure ratio on the tensile properties of X80 pipeline steel

2015 ◽  
Vol 40 (35) ◽  
pp. 11925-11930 ◽  
Author(s):  
Pengyan Wang ◽  
Jian Wang ◽  
Shuqi Zheng ◽  
Yameng Qi ◽  
Maoxian Xiong ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Tensile Properties ◽  
Pipeline Steel ◽  
Pressure Ratio ◽  
X80 Pipeline Steel ◽  
Partial Pressure Ratio

scholarly journals Sulfide Stress Cracking of C-110 Steel in a Sour Environment

2021 ◽  
Vol 2 (3) ◽  
pp. 376-396
Author(s):  
Sagar Tale ◽  
Ramadan Ahmed ◽  
Rida Elgaddafi ◽  
Catalin Teodoriu
Keyword(s):  
Partial Pressure ◽  
Hydrogen Permeation ◽  
Pressure Ratio ◽  
Optical Microscope ◽  
Mixed Gas ◽  
Stress Cracking ◽  
Sulfide Stress ◽  
Sulfide Stress Cracking ◽  
Partial Pressure Ratio ◽  
Grade Steel

The scope of this study includes modeling and experimental investigation of sulfide stress cracking (SSC) of high-strength carbon steel. A model has been developed to predict hydrogen permeation in steel for a given pressure and temperature condition. The model is validated with existing and new laboratory measurements. The experiments were performed using C-110 grade steel specimens. The specimens were aged in 2% (wt.) brine saturated with mixed gas containing CH4, CO2, and H2S. The concentration H2S was maintained constant (280 ppm) while varying the partial pressure ratio of CO2 (i.e., the ratio of partial pressure of CO2 to the total pressure) from 0 to 15%. The changes occurring in the mechanical properties of the specimens were evaluated after exposure to assess material embrittlement and SSC corrosion. Besides this, the cracks developed on the surface of the specimens were examined using an optical microscope. Results show that the hydrogen permeation, and subsequently SSC resistance, of C-110 grade steel were strongly influenced by the Partial Pressure Ratio (PPR) of CO2 when the PPR was between 0 and 5%. The PPR of CO2 had a limited impact on the SSC process when it was between 10 and 15 percent.

Corrosion Behavior of X70 Pipeline Steel and Corrosion Rate Prediction Under the Combination of Corrosive Medium and Applied Pressure

2017 ◽  
Author(s):  
Kaikai Li ◽  
Wei Wu ◽  
Guangxu Cheng ◽  
Yun Li ◽  
Haijun Hu ◽  
...  
Keyword(s):  
Natural Gas ◽  
Corrosion Rate ◽  
Tensile Stress ◽  
Partial Pressure ◽  
Corrosion Behavior ◽  
Pipeline Steel ◽  
Applied Pressure ◽  
Chloride Concentration ◽  
X70 Pipeline Steel ◽  
Co2 Partial Pressure

Natural gas transmission pipeline is prone to internal corrosion due to the combination of corrosive impurities in the pipe (such as CO2, H2S and chlorides) and applied pressure of the pipeline, which seriously affects the safe operation of the pipeline. In this work, the corrosion behavior of a typical X70 pipeline steel was investigated by using potentiodynamic polarization and electrochemical impendence spectroscopy (EIS). The polarization and EIS data under different CO2 partial pressures (0–1 atm), H2S concentrations (0–150 ppm), chloride concentrations (0–3.5 wt%) and tensile stress (0–400 MPa) were obtained. The results show that corrosion rate increases with the increase of CO2 partial pressure and chloride concentration, respectively, while first increases and then decreases with the increase H2S concentrations. The corrosion rate is less affected by elastic tensile stress. In addition, a quantitative prediction model for corrosion rate of natural gas pipeline based on adaptive neuro-fuzzy inference system (ANFIS) was established by fitting the experimental data which maps the relationship between the key influencing factors (i.e. CO2 partial pressure, H2S concentration, chloride concentration and tensile stress) and the corrosion rate. The prediction results show that the relative percentage errors of the predicted and experimental values are relatively small. The prediction accuracy of the model satisfies the engineering application requirement.

Microstructure and Properties of TiAlN Compound Films Fabricated on AZ91D Alloy by Magnetron Sputtering

2011 ◽  
Vol 686 ◽  
pp. 589-594 ◽  
Author(s):  
Sheng Lu ◽  
Liang Wen Wu ◽  
Jing Chen
Keyword(s):  
Corrosion Resistance ◽  
Magnetron Sputtering ◽  
Partial Pressure ◽  
Pressure Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microstructure And Properties ◽  
Az91d Magnesium Alloy ◽  
Hydrophobic Nature ◽  
Partial Pressure Ratio

By means of reaction magnetron sputtering, TiAlN ternary compound films were deposited on AZ91D magnesium alloy substrates. The influence of partial pressure ratio of N2 to Ar (N2/Ar) on the microstructure and properties of TiAlN film was explored with scanning electron microscopy (SEM), X-ray diffraction (XRD), and tests of microhardness, hydrophile and corrosion resistance. The results show that with the increase of N2/Ar partial pressure ratio from 0.5:10 to 1.5:10, Ti2N becomes the main film phase and the size of the crystals cluster decreases. As the N2/Ar ratio is as higher as 2:10, the film crystals change from Ti2N to TiN with coarse clusters. With increase of N2/Ar rate, the hardness, hydrophobic nature and corrosion resistance of the TiAlN film tend to increase.

Sign in / Sign up

Export Citation Format

Share Document