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Erosion corrosion is encountered in many areas of industry and is a very complex phenomenon. In this study, it is aimed to investigate the effects of erosion corrosion in elbow pipes with different shear moduli, velocities of fluid, density of pipe using Ansys Workbench Explicit Dynamics module which is computer-aided and based on finite element. Statistical analyses were also performed to obtain the best flow parameters. SolidWorks program was used for three-dimensional studies considering elbow pipe design. The fluid properties and physical conditions were applied to the three-dimensional solid model in the pipe flow analysis. At the end of the dynamic analysis, erosion values (deformation) occurring in the elbow pipes were statistically compared to each other. [ABSTRACT FROM AUTHOR]

The erosion corrosion behavior of two B10 Cu-Ni alloys in a dynamic seawater environment under different flow velocities and erosion time was investigated by using electrochemical techniques and SEM/EDS in a self-made experimental device for erosion corrosion. The results demonstrate that the variation of the corrosion rate of the two alloys with time is similar. The corrosion rate of the two alloys is higher after two hours of immersion and lower after being immersed for eight hours at different velocities. The corrosion resistance of alloy A is generally higher than that of alloy B after being immersed at a flow velocity below 4 m/s for different time. When the flow velocity is higher than 3 m/s and flushing for a long time， the corrosion resistance of alloy B is better. It is related to the grain size and number of twins， as well as the enrichment of Ni and Fe， rather than the chemical states of Ni and Fe. Moreover， Ni and Fe are enriched in the passivation film of the two alloys after long-time immersion at a high flow velocity， which is beneficial for enhancing the corrosion resistance of the passivation film.

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Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, CrNi alloyed coating was deposited on Q235 low carbon steel by arc-added glow plasma depositing technique in order to increase the corrosion resistance property. It was found that the CrNi alloyed coating was composed of face-centered cubic Cr0.7Ni2.9Fe0.36 phase. The EDS results indicated that 7.3 μ m coatings were prepared which was bonded metallurgically with the substrate. The salt spray corrosion test result showed that the corrosion product film of coating was dense while the corrosion film of carbon steel was multilayered in morphology. The corrosion product film of CrNi coating reduced the corrosion rate. However, the corrosion product of Q235 with loose multi-layer structure increased corrosion process. The erosion corrosion properties of carbon steel and coating were tested in NaCl solution with different flowing speed through electrochemical test methods. The erosion corrosion results showed that the corrosion rate of carbon steel was increased in flowing NaCl solution. The corrosion product of CrNi coating could protect inner material in NaCl solution at flowing speed of 2 m·s − 1 to 6 m·s − 1 . [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Paint & Coatings Industry (0253-4312) is the property of Paint & Coatings Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Corrosion is the degradation of metals caused by chemical or electrochemical reactions with their environment. As a result of these reactions, undesirable conditions occur in the physical, chemical, mechanical and electrical properties of metals. These conditions cause parts made of metallic materials to become unusable. Erosion corrosion is one of the most common types of corrosion in fluid transfer. There are several methods for preventing erosion corrosion. First of all, some precautions should be taken to prevent wear. Intervention is very important in terms of cost, especially at the design stage. Measures such as wide angle bends, wall thickness of wear-resistant material and corrosion allowance can be taken, especially in applications where the flow direction needs to be changed. The aim of this study was to determine the effect of liquid fluid on erosion corrosion in Ti6Al4V, 304 stainless steel and MgAz91 elbow pipes by using the computer aided and finite element based AnsysWorkbench Explicit Dynamics module. For the design of the elbow pipe, SolidWorks was used for 3D studies. In the analysis of the pipe, the suitability of the pipe for the 3D model was examined. The effect of fluid rotation on the pipe walls and the effect of the pipe material on the flow along the pipe were determined. The standard k-e model based on the velocity-pressure relationship in continuous and steady flow was used for the flow calculations. The flow simulation showed that for all models the flow accumulation after rotation was more concentrated on the opposite walls of the pipe, as expected. The results obtained showed that the deformation in MgAZ91 material had the highest value at 9.14 × 10−8 mm. This situation has been interpreted to mean that it may vary depending on the flow rate automation. Designs on the old designs in the erosion structure of the liquid that occurs in the pipes with a new product design in the analysis design.

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the comprehensive performance of TC11 titanium alloy and make it more widely used in the field of oil and gas wells, cobalt oxide micro‐powder from 0 to 0.8 g·L−1 was added in the electrolyte. The effects of cobalt oxide micro‐powder concentration on properties of micro‐arc oxidation (MAO) coatings were analyzed by scanning electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, and electrochemical workstation. With cobalt oxide micro‐powder increased, the oxide voltage increased, and the discharge coating micropores became more uniform. The increase in thickness and hardness also improved corrosion resistance. The comprehensive performance after added 0.6 g·L−1 of cobalt oxide was the best, with a doubling increase in thickness and hardness, reaching 32.1 µm and 721.2 HV, respectively. The corrosion rate reduced to 4.19 × 10−10 mm·a−1, which reduced by three orders of magnitude. In addition, the substrates and samples prepared with 0.6 g·L−1 cobalt oxidation were used for the erosion corrosion tests in different NaCl solutions, and it was found that the weight loss and rate of the MAO sample (slight corrosion) were lower than substrates, indicating that the cobalt oxide doped coatings had better corrosion resistance. [ABSTRACT FROM AUTHOR]

Copyright of Corrosion & Protection in Petrochemical Industry is the property of Corrosion & Protection in Petrochemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The corrosion occurred at the entrance pipeline of safety valve at acid water stripping tower top has been analyzed via macromorphology, material quality, metallographic examination and SEM, etc. The results show that the corrosion and perforation is caused typically by ammonium salt corrosion under scale, erosion corrosion and cavitation corrosion at presence of acid water and vapour. Thus, several countermeansures are given to solve the corrosion problems. It is helpful for reduction of corrosion, improvement of service life of pipeline at acid water stripping tower top, and ensurance of long-term safety production. [ABSTRACT FROM AUTHOR]

For the corrosion perforation failure of oil country tubular goods in an offshore oil field. the overall failure cause was studied by the operation history analysis, material evaluation. macro analysis, SEM micro analysis, energy spectrum (EDS) analysis, corrosion simulation test of autoclave, laser scanning confocal microscope (LSCM) measurement technology. The analysis results show that the corrosive gas CO2 and H2S was detected and the formation output had a small amount of sand in the well condition. The chemical composition. metallographic structure and mechanical properties of the perforation pipe meet the requirements of product standard. The corrosion morphology of the perforation was characterized by fluid erosion. The corrosion products mainly include C. O. Sand Fe elements. which were CO2 and H2S corrosion products. The corrosion simulation test with a velocity of 3 m/s induced local corrosion, Perforation failure is a synergistic effect of corrosion and erosion. [ABSTRACT FROM AUTHOR]

The two-step process of electroless plating and electrodeposition was used to successfully prepare a bilayer composite film by electroplating a Ni–Cu–P film with hydrophobic properties on the Ni–P film. The histological features of the two membrane layers were compared. The L360 pipeline steel, Ni–P coating and Ni–Cu–P composite film were evaluated by electrochemical test and erosion corrosion method. Under simulated seawater conditions, the material properties changed before and after different periods of service. The experimental results show that the introduction of Cu can inhibit the growth of cellular structures on the surface of the coating, increase the number of nucleation points, and improve the microstructure of the coating during the deposition of Ni–Cu–P films. The Ni–P/Ni–Cu–P bilayer composite film has a pinecone-like convex structure, which can greatly reduce the surface energy of the film layer and endow the film layer with hydrophobicity. At the same time, it effectively resists the adsorption of water and other external impurities on its surface, and has good anti-fouling performance, thereby slowing down the surface corrosion and improving corrosion resistance. In addition, copper enables the composite coating to have passivation and a uniform and dense coating structure, which is the main reason for the improvement of the corrosion protection performance of the composite coating. The protective effect of the coating can effectively improve the electrochemical resistance and erosion resistance of L360. The Ni–P/Ni–Cu–P bilayer composite film reduces the electrochemical corrosion rate of the substrate from 0.417mmpY to 0.025mmpY, and the scouring weight loss rate of the film decreases to 0.05% of the substrate.

Erosion‐corrosion (E−C) is one of the most intense forms of metal degradation observed whenever a static metallic material is in contact with dynamic liquid. Efficiency of industrial plant mainly depends upon the condition of various components of the equipment. Collective mechanism of corrosion and erosion results in severe surface deterioration with heavy material loss due to synergistic effect. Erosion‐corrosion is mainly observed in the pipelines used in oil and gas industries, petroleum industries, heat exchanges and mainly in marine equipment. Free flowing saline water, containing different grades of sand particles adversely affect marine equipment. Numerous reports are available discussing the impact of erosion‐corrosion in chemical industries. Single report documenting all types of prototypes, comparative study of erosion corrosion of various engineering materials and control techniques is highly limited. This review gives vivid account of various types of prototypes, comparative study of erosion‐corrosion of various engineering materials, various factors affecting tribology of system and control techniques is a systematic way. Application of corrosion inhibitors appears to be an effective method to reduce erosion‐corrosion. This review highlights the importance of understanding the mechanism of erosion‐corrosion in industrial equipment and provides a succinct overview of erosion‐corrosion synergism. [ABSTRACT FROM AUTHOR]

This paper presents the investigation of corrosion of 15Mo3 pipe in the steam heater system of the Plomin thermal power plant. Corrosion damage led to a rupture in the system as well as delays. Therefore it was necessary to determine the type and the cause of the corrosion. Corrosion is classified according to three factors: the mechanism, the specificity of its occurrence, and the form of the corrosion attack. Power plants are explained with an emphasis on thermal power plants, along with an analysis of the sample and system in which the damage occurred. The results of the investigation of corrosion products on the pipe and the rupture itself are presented. Chemical analysis, microscopic research with light and electron microscopy, hardness tests according to Vickers, and analysis with FT-IR spectroscopy were carried out. Erosion corrosion was proven to be the cause of the failure in a specific example. [ABSTRACT FROM AUTHOR]

In SCAL indirect air-cooling system， the aluminum pipe orifice of radiator is the position most easily to be corroded. Water leakage even occurs at this position in some units. Clarifying the corrosion type and key influencing factor of water quality can provide guidance for chemical operators and ensure the stable operation of units. In this paper， the corrosion type of the aluminum pipe orifice of radiator and key influencing factor of water quality were illustrated by field investigation of three SCAL intercooling system radiators in China， the analysis of the water quality data and suspended substance composition as well as laboratory simulation test. Results showed that aluminum pipe orifice corrosion in the radiator of SCAL indirect air-cooling system was erosion corrosion. With the same material and fluid flow state， when the pH value of circulating water increased to 9.5， it could obviously accelerate the erosion corrosion of aluminum pipe orifice， which could lead to corrosion damage of aluminum pipe orifice in a short time. This was the key influencing factor of water quality that increasing the corrosion of pipe orifice.Chemical operators should strengthen the detection of pH value of circulating water and adjust it timely.

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Erosion‐corrosion (E−C) is one of the most intense forms of metal degradation observed whenever a static metallic material is in contact with dynamic liquid. Efficiency of industrial plant mainly depends upon the condition of various components of the equipment. Collective mechanism of corrosion and erosion results in severe surface deterioration with heavy material loss due to synergistic effect. Erosion‐corrosion is mainly observed in the pipelines used in oil and gas industries, petroleum industries, heat exchanges and mainly in marine equipment. Free flowing saline water, containing different grades of sand particles adversely affect marine equipment. Numerous reports are available discussing the impact of erosion‐corrosion in chemical industries. Single report documenting all types of prototypes, comparative study of erosion corrosion of various engineering materials and control techniques is highly limited. This review gives vivid account of various types of prototypes, comparative study of erosion‐corrosion of various engineering materials, various factors affecting tribology of system and control techniques is a systematic way. Application of corrosion inhibitors appears to be an effective method to reduce erosion‐corrosion. This review highlights the importance of understanding the mechanism of erosion‐corrosion in industrial equipment and provides a succinct overview of erosion‐corrosion synergism.

• The air cooler tubes air cooler tubes at the top of the distillation column suffered from severe leakage during service. • CFD simulation are used to analyze the corrosion behavior of the atmospheric pressure air cooler tubes and the simulation results are validated by experiments. • The gas–liquid erosion corrosion is the main reason for the leakage and the impact angle is the key factor that affects the corrosion. • An improvement measure has been proposed and the corrosion is greatly alleviated. Air coolers are important heat exchangers and widely used in the petroleum and petrochemical industries. The leakage of air cooler tubes due to corrosion frequently happened and seriously affected normal production process leading to unplanned shutdowns, so the corrosion behavior of the air cooler tubes needed to be clarified urgently. In this work, the corrosion behavior of the atmospheric pressure air cooler tubes was investigated by computational fluid dynamics (CFD) simulation and experimental study. It was depicted that the gas–liquid erosion corrosion was the main reason for the leakage of air cooler tubes and the collision angle between the fluid flow and the wall at the inlet of the tubes was the key factor that affects the corrosion behavior of the multiphase flow inside the air cooler tubes. The corrosion was most severe when the collision angle is 30 degree. With the purpose to migrate corrosion, the improvement measure was proposed from the perspective of collision angle elimination. The porous plates were installed and the lifetime of the air cooler tubes was extended to 4 times that of the original conditions, which indicated the installation of porous plates is an effective measure to reduce corrosion. [ABSTRACT FROM AUTHOR]

• Ethanolamine steam ammonia tower system corrosion phenomena reported. • The solution of ammonia water and ethanolamine accelerated intergranular corrosion. • Ethanolamine degradation triggers stainless steel corrosion. • Fluid flushing accelerates stainless steel corrosion. The ammonia distillation tower in the ethanolamine production process is responsible for removing ammonia gas from the product, and the bottom reflux system continuously provides heat to the distillation tower through heat exchangers. Addressing the corrosion issues of the impeller and inlet filter cartridge of the tower base pump, through macroscopic analysis, metallographic analysis, SEM, EDS, and other means, it was found that the impeller is made of CF-8 M stainless steel with a continuous dendritic structure. The surface of the impeller has experienced grain detachment both internally and externally, displaying typical intergranular corrosion morphology, with the residual lamellar Cr-rich grain boundaries undergoing thinning under fluid impingement. The pump inlet filter cartridge is made of 304 stainless steel with an austenitic structure containing partial twinning. The corrosion morphology mainly exhibits impingement thinning, with intergranular corrosion occurring in the weld seam region, where the corrosion rate is higher. EDS surface scanning of the impeller structure revealed severe element segregation within the structure, with chromium enrichment and nickel depletion at grain boundaries causing severe intergranular corrosion. Computational Fluid Dynamics (CFD) simulation analysis of the pipeline where the filter cartridge is located identified accelerated flow velocities in certain regions due to throttling characteristics of the filter plate, leading to increased shear stress between filter orifices and enhanced corrosion rates. At the rear end of the filter cartridge, where the flow velocity is close to zero due to blind plate effects, no significant corrosion was observed. Therefore, the corrosion failure reasons in the bottom reflux system of the ammonia distillation tower involve a combination of intergranular corrosion and impingement corrosion. When sensitization occurs in stainless steel, intergranular corrosion predominates with impingement corrosion as secondary. In the absence of sensitization, impingement corrosion primarily occurs, with faster flow rates and higher shear stresses leading to increased corrosion rates. When the flow rate is zero, no corrosion takes place. [ABSTRACT FROM AUTHOR]

The project involved designing, constructing and commissioning a cathodic protection system for a selected spiral classifier operating at the KGHM Polska Miedź S.A. Ore Concentration Plant (O/ZWR). The authors developed a concept and assumptions regarding the corrosion protection of a large industrial device using a cathodic protection system with an external power source. Pre-project studies included conducting a trial polarization of one of the 28 classifiers operating at O/ZWR. The obtained results enabled the determination of the protective current demand required and the selection of a target polarization device, ensuring the flow of current with an intensity that guarantees that the required corrosion protection level will be achieved. The ultimately installed cathodic protection system consisted of an external cathodic protection current source with maximum output parameters of 50V/20A, a power supply system and a polarization anode system. Elements for monitoring corrosion occurring during system operation were installed, which employed reference electrodes of zinc (Zn) and silver chloride (Ag/AgCl) to measure the potential of the structure under cathodic protection. Furthermore, resistive corrosion sensors were installed to measure the steel corrosion rate under polarization conditions, making it possible to assess the effectiveness of the protection. The system will also be equipped with a prototype system for remote monitoring of the operation of the protection system, enabling online observation and analysis of settings and temporary indicators influencing the ongoing corrosion processes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of National University of Defense Technology / Guofang Keji Daxue Xuebao is the property of NUDT Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• The corrosion failure cause of sour water stripper was thoroughly investigated. • Identify Fe 4 [Fe(CN) 6 ] 3 and FeS as the predominant corrosion products. • The interaction of electrochemical corrosion and fluid erosion was the primary culprit for stripper failure. • Corrosion prevention and control countermeasures were developed based on a comprehensive analysis of the failure. In this paper, a study was performed on the corrosion failure of a sour water stripper in a coal chemical plant. Two field samples of 316L stainless steel taken from the most corroded areas were used for failure analysis. Instruments including ultrasonic thickness gauge, super-depth-of-field microscope (SDFM), scanning electron microscopy with energy dispersive spectrometer (SEM-EDS) and X-ray diffraction (XRD) were applied to test the samples. All test experiments were carried out under normal temperature and pressure working conditions, except for the vacuum environment of SEM-EDS. Besides, the chemical compositions of various process mediums were statistically analyzed. The results showed that the process medium composition fluctuated dramatically, and NH 3 -N content in the feed reached a maximum of 3750 mg/L, which was as much as 12.5 times the design value. The stripper wall was severely thinned, with the overall thickness reduced by more than 50 %. It was depicted that the typical morphology of corroded surfaces mainly consists of three regions of corrosion pit region, pore region and rough region. The corrosion products contained over 20 % nitrogen and a small amount of sulphur, identifying the phase composition as Fe 4 [Fe(CN) 6 ] 3 and FeS. The interaction of electrochemical corrosion and fluid erosion was the major reason for stripper failure. In addition, the extreme conditions resulting from the unstable operation further accelerated the corrosion process. To avoid future failures, optimizing the operational parameters of upstream units, reducing the operational load of the stripper, reselecting the inner wall material and adopting the advanced corrosion monitoring system were recommended. [ABSTRACT FROM AUTHOR]

Objective In view of the serious corrosion problems faced to the gathering and transportation system of shale gas fields, systematic analysis and simulation evaluation were used to study the corrosion behavior and laws at different stages to clarify the main reasons for corrosion and countermeasures. Methods The main corrosion factors were systematically analyzed for the serious corrosion problems of gathering and transportation system in shale gas field, and according to the corrosion characteristics of the system, the shale gas development was divided into one drainage gas recovery stage and two stages of production, and the corrosion behavior and laws of different stages were studied by weight loss, SEM, EDS, XRD and other methods. Results The corrosion is dominant in the places where the sand content and fluid state change greatly, it was appeared as plough-type damage, and supplemented by electrochemical corrosion under the condition of flow velocity of 5-18 m/ s. As the flow rate decreased, the corrosion characteristics was changed by deposition of sand and flow back fluid, which makes it clear that the coexistence of SRB and carbon dioxide is the main reason for the perforation failure of gas gathering pipeline. The on-site working conditions of SRB film formation were simulated, a pitting corrosion rate of 5. 86 mm/a, it was equivalent to the part of the failure pipeline. Conclusions A feasible and practical corrosion control scheme was proposed, mainly including using erosion-resistant materials, increasing wall thickness, adding sterilization and corrosion inhibitors, and applying them to the shale gas field to reduce the failure of the gathering and transportation system by more than 90 % [ABSTRACT FROM AUTHOR]

There has been a significant increase in the failure of pipes used for recirculating hot water systems installed in hospitals, apartment blocks, and hotels in recent years. The rise has occurred as these systems have increased in popularity, and thermostatic mixing valves have made the higher operating temperatures in recirculating systems safe. A common theme tends to be the continuous flow of water above 65°C (150°F) at velocities that have been found acceptable for non-continuous flow. Failures have been experienced in pipes made from both copper and polypropylene random copolymer. Explanations have been slow to emerge and are still subject to debate, particularly as to the initiating causes of pin-hole corrosion (one of the more common modes of failure). Since it is not possible to view the initiation of the pin hole, proof of the cause of the initiation is still unknown. There are indications from consistent correlations between operating conditions and the onset of pin-holing corrosion that are used by authorities as the basis of modifications to design and installation standards to minimize occurrence. This paper will cover some of the background, myths, and current thinking on the causes of the problem in both copper and polypropylene from the point of view of a forensic engineer trying to make sense of uncertain science and the complications of a problem that is transdisciplinary in nature. [ABSTRACT FROM AUTHOR]

The project involved designing, constructing and commissioning a cathodic protection system for a selected spiral classifier operating at the KGHM Polska Miedź S.A. Ore Concentration Plant (O/ZWR). The authors developed a concept and assumptions regarding the corrosion protection of a large industrial device using a cathodic protection system with an external power source. Pre-project studies included conducting a trial polarization of one of the 28 classifiers operating at O/ZWR. The obtained results enabled the determination of the protective current demand required and the selection of a target polarization device, ensuring the flow of current with an intensity that guarantees that the required corrosion protection level will be achieved. The ultimately installed cathodic protection system consisted of an external cathodic protection current source with maximum output parameters of 50V/20A, a power supply system and a polarization anode system. Elements for monitoring corrosion occurring during system operation were installed, which employed reference electrodes of zinc (Zn) and silver chloride (Ag/AgCl) to measure the potential of the structure under cathodic protection. Furthermore, resistive corrosion sensors were installed to measure the steel corrosion rate under polarization conditions, making it possible to assess the effectiveness of the protection. The system will also be equipped with a prototype system for remote monitoring of the operation of the protection system, enabling online observation and analysis of settings and temporary indicators influencing the ongoing corrosion processes.

In this study, the Fe-Cr-Ni-Si and WC alloy coatings were deposited on the polished 2Cr13 steel samples by using a laser cladding technique. The microstructure, tribology and erosion-corrosion resistance properties of laser cladding coatings were investigated, and the influence of WC proportion on properties of coatings were analyzed. The research results show that the ratio of WC in alloy powders affects obviously the tribology and erosion-corrosion resistance properties of laser cladding coatings, when the ratio of WC in alloy powders is 20%, alloy coating possesses excellent properties of hardness, wear-resisting and erosive-corrosive resistance, which can prolong effectively the operating life of equipment. [ABSTRACT FROM AUTHOR]

The liquid-solid erosion-corrosion behavior of aluminum in artificial seawater medium at open circuit has been investigated using a submerged jet impingement rig. The aluminum alloy 6061 coupons subjected to erosion corrosion condition were placed normal to the impinging jet. The gap maintained between the nozzle and the specimen was 5mm. In the present study, sea sand was used as an erodent. Erosion corrosion rate was measured using potentiodynamic polarization and electrochemical impedance spectroscopy methods. At a flowrate of 4 lpm passivation was observed in the potentiodynamic polarization plot which was confirmed by the appearance of inductive loop in the Nyquist plot. At higher flowrates no such condition was observed. The system response to impedance studies was characterized by a high frequency capacitive loop and a capacitive loop at the lower frequency. Surface morphology was studied with scanning electron microscopy (semi quantitative analysis) and atomic force microscopy techniques. Elemental mapping was done with electron dispersive X-ray studies. The erosion-corrosion rate increased with increase in the flow rate and temperature. The results of this work will aid in the selection of material for controlled or reduced material loss in sea water circulating equipment’ and pipelines.

Today, conventional machining with chip or machining without chip machining manufacturing methods is used to bring to the desired dimensions sizes the machines and equipment used in the industry. However, non-traditional manufacturing methods are used in cases where traditional machining manufacturing methods are inadequate. Cutting with water jet which is one of the non-traditional manufacturing methods is commonly used in several fields of industry. Unlike traditional manufacturing methods such as turning and milling, not using of a physical cutting tool is among the advantages of the method. Abrasive water jet manufacturing method was started to be applied by adding abrasive particles in the water jet. Apart from the superior properties of the method, possible damages occur in the water jet nozzle due to processes such as cutting or drilling by applying high pressure. Erosion-corrosion is the leading damage among these damages. In this study, the erosion-corrosion in the nozzle caused by high-pressure water and abrasive during the abrasive water jet cutting process was simulated in the computer environment. In this paper, the erosion rate in the nozzle was calculated as 6,90E-06 kg/m2 s. This value was converted as 0,30 mm (27,09 mm for yearly) via developed software for 100 h. [ABSTRACT FROM AUTHOR]

The initial processes that take place in the operating facilities of the pressure reduction station on natural gas do not remove all its pollutants, whether moisture or solid particles. Under such conditions, corrosion in pipelines, blockage of instrumentation equipment, and destruction of valves and regulators will be intensified, so it is necessary at distribution and pressure reduction stations to prevent gas pressure drop and damage to pipeline equipment, processes to separate solid particles. And liquefied droplets of natural gas. This report first defines natural gas flow erosion and then briefly describes the flow erosion using the Discrete Phase Method DPM and the Eulerian-Lagrangian biphasic flow, or the discrete phase abbreviated simulation using Ansys Fluent 2019R1 software. The gas-solid in the elbow deals with the welding of this elbow joint. This report describes the discrete and continuous phase flow equations. In this regard, to consider the perturbation effects of the energy-perturbation loss model (Realizable k-ε), to model the behavior of particles in the vicinity of the wall and also the scattering of particles due to perturbation in the fluid phase is modeled using random tracing model. . The boundary conditions of solid particles colliding with the wall and the steps of numerical solution of the equations in the discrete phase method are explained and the present effect investigates the erosive corrosion. The results show that even in slow currents with low Reynolds number, the gas-solid fluid is heterogeneous, and increasing the diameter of the solid particles increases the heterogeneity of the gas-solid flow and ultimately causes more abrasion corrosion at the weld roughness. [ABSTRACT FROM AUTHOR]

In order to prevent the severe corrosion damage ca used by direct contact between base material of the pipeline and conveying medium, internal coating is widely applied in the development of acidic gas wells in Sichuan Chongqing gas field. Factors such as corrosion characteristics of the conveying medium and high flow rate can impact on the internal wall coating of pipelines, and flow rate plays the most crucial role. In this paper, the erosion resistance and electrochemical corrosion resistance of three different inner coatings were tested under the set conditions. The outcome suggests that the corrosion resistance of the coating decreases with the increases of corrosive medium velocity under the condition of erosion. When the flow rate increases, the spectral radius of three coatings decrease, which indicates that the erosion resistance of coatings decreases with the increase of velocity [ABSTRACT FROM AUTHOR]

Corrosion is one of the main factors that determine the operational lifetime of any type of thermal power station. The ITER In-Vessel design includes coolant water interfaces with the copper alloy CuCrZr that are exposed to high flow velocities. These interfaces are near the plasma and thus subject to oxidants such as H2O2 generated through irradiation-induced radiolysis of the coolant water when the plasma is active. The erosion corrosion and release rates of CuCrZr and CuCrZr/316L(N)-IG joints were derived from weight change data and metallographic examinations of specimens after autoclave exposures at 110°C, 150°C and 250°C at reducing-, oxidizing- and cyclic redox water chemistry conditions. Reducing water chemistry represents periods considered as the nominal off-plasma operational conditions while the oxidizing environment simulates situations when the plasma is active. The cyclic redox conditions represent periods with shorter cycles simulating plasma activations with subsequent periodical variation of the water chemistry from reducing to oxidizing. The erosion corrosion rates for CuCrZr at active plasma conditions were 20 and 40µm/year at 110 and 150°C. At 250°C the corresponding rate was much higher. This result gives important information on what may happen if, for example, a First Wall panel is exposed to an unexpectedly high heat flux. Under reducing conditions the erosion corrosion rates were 3µm/year and 20µm/year at 110°C and 250°C respectively. The results at 250°C under off-plasma conditions reveal that the effect of erosion corrosion also has to be taken into account during baking. Cyclic conditions with respect to oxidant content turned out to be the most demanding environment (more demanding than pure oxidizing conditions) for the CuCrZr-alloy. Erosion corrosion rates of 90µm/year and 370µm/year at 110 and 150°C were recorded respectively. The highest temperature 250°C was not tested. This raise the question whether measures should be introduced that renders the system either oxidizing or reducing. In summary, the erosion corrosion rates recorded for CuCrZr under simulated ITER coolant water conditions are high, especially during plasma operation. For comparison it can be mentioned that corrosion rates of structural materials in the primary loop of light water reactors generally are considerably lower than 1µm/year. The estimated rates for CuCrZr are then 1–3 orders of magnitude higher, however the short total duration of plasma operation during ITER life time must be considered in this context. Erosion corrosion of CuCrZr can potentially cause problems for the ITER coolant systems and the chemical control systems.

Polarization curves and mass losses of SAF3207 hyper-duplex stainless steel under various conditions were measured. The damaged surfaces after erosion–corrosion tests were characterized by scanning electron microscopy. The results showed that an increase in flow velocity could enhance the electrochemical corrosion and consequently decrease the passivation properties of the steel. The erosion–corrosion damage of the samples increased substantially when the flow velocity exceeded the critical value of 4 m·s−1. The mass loss rate increased as the sand content increased, reaching a maximum at 7wt% sand content, corresponding to the most severe electrochemical corrosion damage. When the sand content was increased further, however, the mass loss rate decreased and then tended stable. The mass loss was divided into incubation, sustained, and stationary periods, with a maximum mass loss rate of 12.97 g·h−1·m−2 after an erosion period of 2.5 h. The erosion–corrosion mechanism was investigated in detail. [ABSTRACT FROM AUTHOR]

Abstract The investigation of steel corrosion has been done in a multiple flow loop (corrosion test rack) under hydrodynamic condition. Further, the performance of rice straw extracts (RSE), lignin (L) and ethylene glycol (EG) to inhibit the corrosion were studied through weight loss analysis. The data has been tabulated based on the different position of steel specimen in corrosion test rack; middle, elbow and the end of the rack. The initial study was performed at 30 °C of 3.5% NaCl alone and showed slight corrosion damage with the appearance of pitting and oxide growth. The degradation of steel surface was depending on its position in the rack which experienced different flow. A study at 40 °C with inhibitor solution revealed a significant inhibition. NaCl alone and EG exhibited severe corrosion at the end of the rack. In contrast, the use of RSE and lignin inhibitors reduced the corrosion attack significantly at the end of the rack. The effectiveness of the corrosion inhibitors was depending on the chemical constituents, structure, functional groups as well as the composition of the compounds. The order of the best performance of corrosion inhibitor was; RSE > L > EG. Localized pitting corrosion is a primary type of corrosion attack before general and erosion-corrosion take place. Highlights • Corrosion configuration and inhibition of steel in multiple flow loop were studied via weight loss method. • Morphology studies were performed via high-resolution optical camera, microscopic analyser and scanning probe microscope. • The difference in corrosion damage resulted from the difference of fluid flows as well as a different corrosion inhibitor. • The steel at the end of the rack exhibited very less corrosion effect whenever exposed to RSE inhibitors. [ABSTRACT FROM AUTHOR]

This paper summarizes the anti-corrosive and anti-erosive properties of water-ethylene glycol based commercial coolant dispersed with nanomaterials. Multiwalled carbon nanotubes (MWCNTs), silver nanoparticles (Ag) and nanosized alumina particles (Al2O3) are dispersed in 0.5% weight in automotive coolants and tested for anti-corrosive properties as per ASTM standards. Prior to dispersion, the nanomaterials are surface modified to get good stability in coolant solutions. The corrosion resistance is measured in terms of weight loss of materials that is commonly used in automotive systems. It is found that oxidized MWCNTs are suitable to automotive systems while silver and Al2O3 nanoparticles are found to be deleterious in nature. [ABSTRACT FROM AUTHOR]

The liquid-solid erosion-corrosion behavior of aluminum in artificial seawater medium at open circuit has been investigated using a submerged jet impingement rig. The aluminum alloy 6061 coupons subjected to erosion corrosion condition were placed normal to the impinging jet. The gap maintained between the nozzle and the specimen was 5mm. In the present study, sea sand was used as an erodent. Erosion corrosion rate was measured using potentiodynamic polarization and electrochemical impedance spectroscopy methods. At a flowrate of 4 lpm passivation was observed in the potentiodynamic polarization plot which was confirmed by the appearance of inductive loop in the Nyquist plot. At higher flowrates no such condition was observed. The system response to impedance studies was characterized by a high frequency capacitive loop and a capacitive loop at the lower frequency. Surface morphology was studied with scanning electron microscopy (semi quantitative analysis) and atomic force microscopy techniques. Elemental mapping was done with electron dispersive X-ray studies. The erosion-corrosion rate increased with increase in the flow rate and temperature. The results of this work will aid in the selection of material for controlled or reduced material loss in sea water circulating equipment' and pipelines. [ABSTRACT FROM AUTHOR]

In synthesis of metastannic acid, erosion corrosion caused by strong acid and abrasion triggered by stannum granular both create a complex circumstance for reactor. Titanium and zirconium, as the major choices for fabricating the reactor, sustained the combined impact of corrosion and abrasion in the circumstance. While there are very few researches, focusing on the erosion corrosion of the reactor, in the synthesis of metastannic acid. The erosion corrosion behaviors of commercial reactor materials Ti (TA2) and Zr (Zr-1) were investigated in the acidic conditions (20 vol% H _2 SO _4 or 20 vol% HNO _3 solutions) according to the complex circumstance. Therefore the wear and corrosion properties were tested by weight loss method and electrochemical method separately, the corrosion situation, such as open circuit potential (OCP) and Tafel plot, of Ti and Zr were tested, the mass loss caused by corrosion and wear were quantitatively, and the surface morphology was observed by scanning electron microscope (SEM). Moreover the corrosion abrasion situation, OCP, Tafel plot, mass loss and surface morphology, had been investigated using self-made corrosion abrasion testing device too. The results showed that in the solution of 20 vol% HNO _3 , the corrosion rate of Zr increased by 120 times when the solution was heated to 200 °C under corrosion condition, and the corrosion rate of Ti increased by 8 times, indicating that the corrosion resistance of Zr is easier affected by temperature, the corrosion resistance of Zr is better than Ti. Under abrasion condition, using abrasion quartz sand particles as abrasion material, the mass loss rate of Ti and Zr was 159.23 mg/(m ^2 ·h) and 252.23 mg/(m ^2 ·h). Under erosion corrosion condition, the synergistic effect of erosion corrosion of Ti and Zr exacerbated the mass loss, their mass loss rate respectively was 788.05 mg/(m ^2 ·h) and 225.4 mg/(m ^2 ·h) especially in Ti-H _2 SO _4 and Zr-HNO _3 systems. A dense oxide layer detected on the surface of Ti and Zr, could improve the corrosion resistance, but it was easy to fatigue and peel off when there was abrasion material in the solution. A erosion corrosion model of Ti and Zr were established for serve life prediction, which could provide theoretical guidance for the design of reaction in production of metastannic acid.

To optimize the operating temperature and flow velocity of cooling water in a high voltage direct current (HVDC) thyristor valve cooling system, the erosion corrosion characteristics of aluminum electrodes in deionized water at various temperatures were studied. With increasing water temperature, the corrosion current of the aluminum electrode gradually increases and the charge transfer impedance gradually decreases, thus, the corrosion of aluminum tends to become serious. The aluminum electrode in 50 °C deionized water has the most negative corrosion potential (−0.930 V), the maximum corrosion current (1.115 × 10−6 A cm−2) and the minimum charge transfer impedance (8.828 × 10−6 Ω), thus, the aluminum corrosion at this temperature is the most serious. When the temperature of deionized water increases, the thermodynamic activity of the ions and dissolved oxygen in the deionized water increases, and the mass transfer process accelerates. Therefore, the electrochemical corrosion reaction of the aluminum surface will be accelerated. The corrosion products covering the aluminum electrode surface are mainly Al(OH)3. With increasing water temperature, the number of pits and grooves formed by corrosion on the aluminum surface increased. In this paper, the molar activation energy Ea and the equilibrium constant K of the aluminum corrosion reaction with various temperatures are calculated. This clarifies the effect of temperature on the aluminum corrosion reaction, which provides a basis for protecting aluminum from corrosion. The results of this study will contribute to research that is focused on the improvement of production techniques used for HVDC thyristor valve cooling systems.