Corrosion is a major cause of the loss of hermeticity in oil and gas pipelines. Corrosion defects affect the remaining life of in-service pipelines and can lead to failures, ruptures, hydrocarbon leakage, product loss, interruptions, environmental damage, economic losses, or, in the worst cases, fatalities. The existence of localized corrosion defects is a significant issue in pipeline integrity analysis, mainly because these structures are commonly buried and cover large extensions, amounting to hundreds or even thousands of miles; thus, it is difficult to size and locate all minor but possibly deep defects. Consequently, probabilistic and statistical modeling methods have been widely used to assess the integrity of corroded pipelines. Statistical modeling methods used to estimate the remaining life of the pipeline have focused on three main aspects: applications to estimate the defect depths and rates of corrosion, Bayesian applications in pipeline integrity to update the probability distribution for corrosion defects (depth, length, and spatial distribution), and pipeline reliability estimations. This paper reviews several methods proposed in the literature for these issues as well as their applications in real life. In addition, some of the present and future challenges related to preventing corrosion in the oil and gas pipeline industry are described.

It is well known that the mechanical properties of a steel plate depend on the anisotropy of the material and the rolling directions. This paper presents the results of the Charpy V-Notch (CVN) impact test for the ST, TL, TS, LS, LT, 45°, and SL directions in API 5L X52 pipelines with electric-resistance-welded (ERW) and seamless (SMLS) pipes. Charpy specimens were manufactured and tested according to the ASTM E23 standard in laboratory conditions. All possible directions in the pipe were tested. Three Charpy specimens were tested for each direction, for a total of 21 Charpy tests. Moreover, the microstructures, hardness, ductile and brittle areas, and fracture surfaces of the Charpy specimens are presented in this research. The results show that the Charpy energy values, hardness, and microstructures depend on the direction of the specimens. The Charpy values of the SMLS pipe are higher than those of the ERW pipe because of several metallurgical factors, such as grain size, non-metallic inclusions, delaminations, and microstructures.

The synthesis of ethylamine-based perovskites has emerged to attempt to replace the lead in lead-based perovskites for the alkaline earth elements barium and strontium, introducing chloride halide to prepare the perovskites in solar cell technology. X-ray diffraction studies were conducted, and EXPO2014 software was utilized to resolve the structure. Chemical characterization was performed using Fourier transform infrared spectroscopy, photophysical properties were analyzed through ultraviolet–visible spectroscopy, and photoluminescence properties were determined to confirm the perovskite characteristics. The software employed can determine new crystal structures, as follows: orthorhombic for barium perovskite CH₃CH₂NH₃BaCl₃ and tetragonal for strontium perovskite CH₃CH₂NH₃SrCl₃. The ultraviolet–visible spectroscopy data demonstrated that a temperature increase (90–110 °C) contributed to reducing the band gap from 3.93 eV to 3.67 eV for barium perovskite and from 4.05 eV to 3.84 eV for strontium perovskite. The results exhibited that new materials can be obtained through gentle chemistry and specialized software like EXPO2014, both of which are capable of conducting reciprocal and direct space analyses for identifying crystal structures using powder X-ray diffraction.

This paper reports a novel coating containing activated TiO₂ for improving corrosion resistance of Cu. In this study, three types of coatings were compared: one made from GPTMS (3-Glycidopropyltrimethoxysilane) (GC1), and two hybrid sol-gel coatings derived from G1 (solution organic) and activated with titanium. The Class I (GC2) coatings contained crystallized TiO₂ particles integrated into the matrix, while the Class II (GC3) coatings used the liquid precursor TTIP (titanium (IV) isopropoxide). The three coatings, with thicknesses of 0.777 ± 0.5 μm (GC1), 2.054 ± 0.5 μm (GC2), and 3.774 ± 0.23 μm (GC3), were analyzed using XRD, optical profilometry, and SEM techniques. GC1 and GC3 exhibited uniform structures, while GC2 showed cracks due to TiO₂ particles. After salt spray exposure per ASTM B117, the coatings were labeled GCE1, GCE2, and GCE3 for evaluation. Salt spray exposure caused SiO₂ precipitates, impacting coating performance. GC3, with TTIP, showed a uniform surface and controlled roughness, leading to superior corrosion resistance (95% efficiency, 2764 Ω), outperforming GC2 (94% efficiency, 1331 Ω) and the substrate (918 Ω). TTIP improved adhesion and barrier formation, while TiO₂ coatings (GC1, GC2) had increased roughness due to particle irregularities. GC3’s thicker, well-integrated structure contributed to its enhanced performance in corrosive environments.

This work shows the effect of artificial aging on the mechanical properties of an API 5L Gr. B steel that undergoes different artificial aging times (0, 500, 1250, and 1500 h). Among the mechanical properties studied are the stress–strain curve, yield stress, and ultimate tensile stress. In addition, the parameters from the Ludwik–Hollomon equation, which are the parameter (K) and the work-hardening coefficient (n), are obtained for the true stress–strain curve. Once the true stress–strain curve is plotted, a 3D model of a transverse crack in a pipeline is proposed. The crack defects are straight, and the finite element method (FEM) is used to determine its behavior at different sizes in order to estimate the failure pressure. It can be said that the mechanical properties (stress–strain curve) increase for an aging time of 500 h compared to the air condition because of the over-aging process, something that is well recognized in the literature. In general, past the over-aging condition, with an increase in the aging time, the mechanical properties tend to decrease. This behavior is similar for the failure pressure. The FEM is sensitive to the decrease in mechanical properties along with the true stress–strain curve.