Introducing New Coating Material Alloy with Potential Elements for High Corrosion Resistance for Oil and Gas Application

In petroleum and petrochemical industries, offshore and onshore systems have to function in an aggressive environment that exposes the production equipment components to thermal cycling and wear and corrosion. Although maintenance of material degradation in oil and gas is costly, internal and external parts of the equipment and pipelines must be well inspected and continually maintained. For this reason, highly advanced corrosion and wear–monitoring systems must be installed in the critical areas of the plant to protect pipes and equipment from seawater and crude oil. Therefore, researchers are in search of advanced materials and methods that could be applied in oil and gas pipelines and accessories for increasing their working time. The common manufacturing processing method for improving the surface of piping and accessories is overlay welding or cladding. This method has some limitations, such as its limitation for choosing materials. In addition, the high temperature of welding causes some defects on the final surface, such as thermal residual stress, cracking, and distortion in the substrate. The method is also time consuming and costly. However, the coating method provides a blend of unique properties with low cost. Thermal spray methods are cold spraying techniques that have a considerably less thermal stress, residual stress, and other defects. Among different thermal spray coating techniques, high-velocity oxygen fuel (HVOF) and plasma are the most commonly used thermal spraying coating processes to produce anti-wear and corrosion coatings with different types of materials such as metal, alloys, and ceramic composite . Furthermore, HVOF and plasma thermally sprayed coating processes induce microstructure heterogeneities, which increase the corrosion and wear resistance. In this research, one type of alloy with chemical composition NiCrCoAlY was chosen for increasing corrosion resistivity of carbon steel piping. A corrosion behavior of coated samples in seawater was investigated for 30 days. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) results indicated that these types of alloys protected the surface of carbon steel piping from harsh environments. However, the corrosion protection of NiCoCrAlY deposited by HVOF technique is higher than a plasma coating technique

Reassessment of the Weather Effect: Stock Prices and Wall Street Weather

Recent research in behavioral finance has investigated whether investors’ mood fluctuations induced by hours of sunshine affect investment decisions in a significant manner such that equity mispricing follows. Some research in this area has concluded that there is a systematic relationship between security markets and local weather, while other research has found no relationship between investment decisions and hours of sunshine. This paper aims to study the weather effect and its possible evolution over time in an effort to consolidate the different findings in the field

Improving corrosion and wear resistance of carbon steel piping system in oil and gas application through thermal spray coating techniques / Mitra Akhtari Zavareh

In petroleum and petrochemical industries, offshore and onshore systems have to function in an aggressive environment that exposes the production equipment components to thermal cycling, wear and corrosion. Although maintenance of material degradation in oil and gas is costly, internal and external parts of the equipment and pipelines must be well inspected and continually maintained. For this reason highly advanced corrosion and wear-monitoring systems must be installed in the critical areas of the plant to protect pipes and equipment from seawater and crude oil. Therefore, researchers are in search of advanced material and methods that could be applied in oil and gas pipelines and accessories for increasing their working time. The common manufacturing processing method for improving the surface of piping and accessories is overlay welding or cladding. This method has some limitations, such as its limitation for choosing materials. In addition, the high temperature of welding causes the final surface has some defects such as, thermal residual stress, cracking and distortion in the substrate. The method is also time-consuming and costly. However, the coating method provides a blend of unique properties with low cost. Thermal spray methods are cold spraying techniques that have a considerably less thermal stress, residual stress and other defects. Among different thermal spray coating techniques, high velocity oxygen fuel (HVOF) and plasma is the most commonly thermal spraying coating process to produce anti-wear and corrosion coatings with different types of materials such as metal, alloys, ceramic composite, etc. Furthermore, HVOF and plasma thermally sprayed coating process induces microstructure heterogeneities, which increase the corrosion and wear resistance. In this research, five different chemical compositions such as alloys and ceramic composite were chosen for increasing corrosion and wear resistivity of carbon steel piping. The chemical compositions are Inconel 625, NiCrCoAlY, Al8Si20BN, Cr3C2-25NiCr and Al2O3- 13%TiO2. For investigating properties of these chemical compositions, potentiodynamic polarization testing, open circuit polarization and electrochemical impedance spectroscopy (EIS) were used in 3.5% NaCl solution (seawater) at 30°C for 30 days. Corrosion was also measured by suspending the samples inside the crude oil at 60°C for 30 days. Measuring corrosion potential and corrosion current density from polarization curves and Tefal slope respectively established the general corrosion ranking of different materials. In addition, the correlation between individual microstructure features and their electrochemical response was established by EIS including equivalent circuit modeling. A wear property of each group of materials was investigated by pin-on-disk machine over a 9048.96 m sliding distance under different loads. The wear rate and weight loss results of each group materials had a different behavior. Some samples were more durable during applying different loads and the rate of weight loss in these samples was very limited. Comparing all the corrosion and wearing results illustrate that the ceramic composite samples have the highest to resistance corrosion and wear behavior. Significantly less effective than the ceramic composite samples, the alloy coated samples showed considerable anti-corrosion and wear behavior

Analysis of corrosion protection behavior of Al2O3-TiO2 oxide ceramic coating on carbon steel pipes for petroleum industry

Corrosion is the deterioration of materials by chemical interaction with their environment. In the oil and gas industry, corrosion of the pipelines and other equipment is one of the leading causes of failure and the corrosion-related costs are very high. Hence, corrosion protection is an essential requirement. In this study, the objective is to analysis of the corrosion protection behavior of spray Alumina-Titania (Al2O3-TiO2) oxide ceramic coating on carbon steel pipes C45 using two different thermal spray coatings processes. These two different thermal spraying coating, High velocity oxy-fuel (HVOF) and plasma thermal spraying techniques can be used instead of extensive treatment by expensive chemical formation of coatings on pipelines and equipment to improve or restore a component's surface properties or dimensions and to protect them from corrosion. Molten or semi-molten ceramic composite powders are sprayed on the surface in order to produce a dense coating layer. FESEM of coated samples showed that a high temperature of plasma coating method end in melting the ceramic powders and creation of completely melted regions on the coated samples’ surface compared to HVOF coating techniques. Corrosion testing of coated samples in seawater (3.5% NaCl) was conducted within 30 days. Electrochemical impedance spectroscopy (EIS) as well as potentiodynamic polarization outcomes represented that the corrosion resistivity of plasma coating technique for this type of ceramic composite is better than HVOF coating technique. However, both types of coating techniques are protecting the substrate against seawater

Comparative study on the corrosion and wear behavior of plasma-sprayed vs. high velocity oxygen fuel-sprayed Al8Si20BN ceramic coatings

Corrosion and wear are common problems encountered in the oil and gas industry. These entail the gradual destruction of materials by mechanical action on the opposite surface, and the chemical and/or electrochemical reaction with their environment. In this research, Al8Si20BN ceramic powder with specific properties against corrosion and wear was selected, and it was sprayed with high velocity oxygen fuel (HVOF) and plasma spray methods onto carbon steel substrates. The coatings were characterized with respect to phase composition, microstructure, microhardness and adhesion strength. Their wear behavior was inspected by applying 5, 10, 15 and 20 N loads by pin-on-disc machine, after which the results of both methods were compared. According to the results, the HVOF-coated models were more durable than the plasma-coated models under different loads in the same condition. In addition, the corrosion deterioration of the coated specimens in both brine (3.5% NaCl) and fossil oil were tested for one month (30 days). Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) assessment in 3.5% NaCl solution indicated that the HVOF-sprayed specimens had better corrosion protection than the plasma-sprayed specimens. Generally, the HVOF technique facilitated more durable coats with greater corrosion and tribological resistance compared to the plasma coating technique