Carbon Steel Pipe Research Articles

Assessment of flow-accelerated corrosion-induced wall thinning in SA106 pipes with elbow sections

A combination of flow-accelerated corrosion (FAC) tests and corresponding computational fluid dynamics (CFD) tests were performed to determine the hydrodynamic parameters that could help predict the highly susceptible location to FAC in the elbow section. The accelerated FAC tests were performed on a specimen containing elbow sections fabricated using commercial 2-inch carbon steel pipe. The tests were conducted at flow rates of 9 m/s under the following conditions: water temperature of 150 °C, dissolved oxygen <5 ppb, and pH 7. Thickness reduction of the specimen pipe due to FAC was measured using ultrasonic testing. CFD was conducted on the FAC test specimen, and the turbulence intensity, and shear stress were analyzed. Notably, the location of the maximum hydrodynamic parameters, that is, the wall shear stress and turbulent intensity, is also the same location with maximum FAC rate. Therefore, the shear stress and turbulence intensity can be used as hydrodynamic parameters that help predict the FAC-induced wall-thinning rate. The results provide a method to identify locations susceptible to FAC and can be useful for determining inspection priority in piping systems.

Residual contact pressure for mechanically lined pipe hydroforming with carrier pipe plastification

Mechanically Lined Pipe (MLP) is a rigid carbon steel pipe internally lined with a flimsy Corrosion Resistance Alloy (CRA). This bi-metal composite structure has become an economic and flexible solution to offshore Oil & Gas (O&G) transportation of highly caustic hydrocarbon fluids. The residual contact pressure that arises from the hydraulic expansion fabrication process may prevent wrinkling and interlayer detachment when the pipe is bent or axially compressed during installation and operation. Increasing the residual contact pressure thus becomes a relevant topic for maintaining MLP integrity. The traditional MLP manufacturing process retains the carrier pipe entirely elastic. Yet, a light degree of plastification of carrier pipe will enhance the mechanical adhesion. Mathematical formulations including linear and Ludwik Power Law (LPL) hardening models are here developed to describe the stress-strain behavior of partially plastified carrier pipe. The stress state analysis is performed throughout the whole fabrication process based on the Tresca criterion. Results for residual contact pressure and residual stress state are obtained analytically and numerically. It suggests that an appropriate plastification of carrier pipe favors the mechanical adhesion.

Effect of Tensile Stress on Self-Magnetic Leakage Field in Carbon Steel Pipe Material

Metal magnetic memory (MMM) technique is a promising non-destructive technology for determining the state of material deformation and structural defect in carbon steel pipe by measuring the self-magnetic leakage field (SMLF). The relationship between SMLF and stress concentration of cracked specimens has been extensively researched, but little is known about corrosion defects in carbon steel pipes, such as circular holes. A static tensile test and MMM measurement were performed on the ASTM A106 Gr. B steel to investigate its applicability in predicting material deformation state and structural defect. The tensile load makes the distribution of self-magnetic leakage field, SMLF intensities in the elastic stage regular. In the defect zone of defective specimens, a peak-trough in the SMLF intensity in the tangential component, Hp(x), and a peak in the normal component, Hp(y), were observed. As yield approached, the SMLF intensities remained unchanged. During plastic deformation, dislocation slip and dislocation interaction rarely change the SMLF intensities and its gradient. The SMLF intensities and its gradient rise as the tensile load approach its ultimate strength. The distribution of SMLF intensities show a peak feature in the Hp(x), and a peak-trough in the Hp(y) as the specimen fractures. Variations in the magnetic and stress fields of carbon steel pipe are caused by structural defect. As a result, the SMLF intensity varies. The method described in this study can be applied to MMM technique to detect material deformation states and defect formation in ASTM A106 Gr. B steel at low cost and with minimal equipment.

Experimental Study on the Simulated Defects Detection in Submerged Transmission Pipeline

Abstract The transport of oil, natural gas, water, and other petrochemical substances is extensively supported by pipelines over long distances. However, long-term use without maintenance causes the residue in the pipeline to gradually settle in the pipeline due to physical or chemical action, and the pipeline becomes an accident. This leads to overpressure and leakages in the pipeline, which in turn affects the safety of the industry and people's lives. This study aims to develop a nondestructive inspection to measure defects in a water pipeline using an ultrasonic technique. An SCH80 carbon steel pipe with a standard thickness of about 11 mm was used for the experiments, and various sets of defects inside and outside of the pipe were simulated, such as holes and grooves. A submerged ultrasonic transducer was used to evaluate the simulated pipeline defects and then acquire the defect data in an imaging system using LabVIEW and origin software. In this way, the thickness and location of the defects were clearly located. In addition, the ultrasonic detection error was calculated to be less than 6.5%. It helps to use this technique and equipment for the inspection of underground fluid pipelines.

An Approach for Grading of Soil Corrosiveness: A Case Study in Vicinity of Ring Road-Kathmandu

Corrosion of the outer surface of underlying Zn-coated or carbon steel pipes in the soil becomes complex and intricate due the insufficient information about the electrochemical interactions between discrete pairs of all corrosive soil factors. To overcome such corrosive problems of the underlying metal pipes in the soil, an ongoing study has suggested a stochastic approach for a close analysis of the corrosive grading of each soil specimen, sampled from the vicinity of Ring Road (RR) of Kathmandu, Nepal, towards the pipes with modifying the previously utilized AWWA (American Water Works Association), ASTM and NACE methods. Four corrosive grades (CGs) of all the soil specimens were categorized based on their quantitatively calculated soil factors in the stochastic approach of the novel probabilistic modeling (NPM) method. Then, they grouped supplementary ten corrosive sub-grades (CSGs) taking the sum of the cumulative point (CuP) of every soil factor. An indeterminate examination of 10 soil specimens was accomplished to categorize their CSGs, which would be a more precise method to draw a corrosive soil mapping of the study areas. The outcomes of such analysis under the NPM method imparted that about 90% of the sampled soil specimens of the RR areas allied only to five specific CSGs belonging to two CGs, i.e., G-RAR and G-MID.

Reducing Corrosion of Carbon Steel Pipes using Cathodic Protection with Anode Separation: A Case Study of Nembe Creek Flow Station

Reducing Corrosion of Carbon Steel Pipes using Cathodic Protection with Anode Separation: A Case Study of Nembe Creek Flow Station

Pengaruh kompensasi, Stres Kerja dan Iklim Organisasi Terhadap Kinerja Karyawan Pada PT Cladtek BiMetal Manufactuing Batam

Human resources (HR) is one of the most important factors in a company that is used to drive other resource activities in running a company. Human resources (HR) have a fairly important position because they have a major role in company activities. PT Cladtek Bi Metal Manufacturing is a company engaged in industrial services for several jobs regarding metal materials, especially the Weld Overlay and Lining processes on carbon steel pipes aimed at industry. Compensation can motivate employees to improve work performance and compensation can also be a tool to provide or increase morale in workers. In terms of compensation at PT Cladtek Bi Metal Manufacturing, there are still some employees who feel that the compensation provided has not fully achieved the satisfaction felt by their employees. Likewise with the incident that occurred at PT Cladtek BiMetal Manufacturing, there were many employees who did not work optimally, this happened because in the assignment of very many responsibilities and also the work received was not in accordance with the field mastered, work deadlines, relationships between colleagues the work is not good and the work done is not in accordance with their abilities. The purpose of this is to determine whether compensation, work stress and organizational climate affect employee performance at PT Cladtek biMetal Manufacturing Batam. The method of data collection is through the distribution of questionnaires with a sample of 200 respondents. The type of research used by the researcher in this research is quantitative research with associative nature of research.

Modeling of Corrosion Rate Under Two Phase Flow in Horizontal Pipe Using Neural Network

The present study develops an artificial neural network (ANN) to model an analysis and a simulation of the correlation between the average corrosion rate carbon steel and the effective parameter Reynolds number (Re), water concentration (Wc) % temperature (T o) with constant of PH 7 . The water, produced fom oil in Kirkuk oil field in Iraq from well no. k184-Depth2200ft., has been used as a corrosive media and specimen area (400 mm2) for the materials that were used as low carbon steel pipe. The pipes are supplied by Doura Refinery . The used flow system is all made of Q.V.F glass, and the circulation of the two –phase (liquid – liquid ) is affected using a Q.V.F pump .The input parameters of the model consists of Reynolds number , water concentration and temperature. The output is average corrosion rate .The performance of the two training algorithms, gradient descent with momentum and Levenberg-Marquardt, are compared to select the most suitable training algorithm for corrosion rate model. The model can be used to calculate the average corrosion rate properties of carbon steel alloy as functions of Reynolds number, water concentration and temperature. Accordingly, the combined influence of these effective parameters and the average corrosion rate is simulated. The results show that the corrosion rate increases with the increase of temperature, Reynolds number and the increase of water concentration.

Analisis Penggunaan Cathodic Protection dengan Metode Sacrificial Anode Sebagai Pengendalian Korosi Pipa Minyak 16 Inci PT. Chevron Pacific Indonesia Simp. Perawang-Minas Area

Cathodic protection is a thermodynamic corrosion control method using metal as the cathode. There are two methods of cathodic protection, namely Sacrificial Anode Cathodic Protection (SACP) and Impressed Current Cathodic Protection (ICPP). This study will analyze the use of Cathodic Protection with the Sacrificial Anode method as corrosion control on a 16 inch oil pipe at PT. Chevron Pacific Indonesia. Carbon steel pipe (API 5L Grade B) with cast magnesium anode material. Calculation of anode requirement for corrosion prevention will be compared with actual field data within 10 years. The calculation results show that the number of calculation parameters used affects the results of the anode requirement on an oil pipe with a length of 16 meters, a diameter of 16 inches, anode with a length of 0.648 m, net weight of anode 7.7 Kg, magnesium anode material with an anode output of 10.8 A/m2, anode density 1765 Kg/m3, wear and tear (volume) 2296 x 10-3 m3 A/y, and a life time of 10 years. Theoretical calculations get 6 anode rods while the actual data requires 8 anode rods.

Testing of Carbon Steel Pipe and Stainless Steel Duplex Pipes of Welding Joints : A Cost and Time Perspective

In the welding process, it is not uncommon for a defect or discontinuity to occur in the welding results. Common defects on the surface are undercut, concavity, incomplete penetration, spatter, burn-through, and mismatch. While defects in internal welds that are often found during testing are porosity, worm holes, slag inclusions, incomplete fusion, and cracks, To obtain pipeline results that comply with the specifications set by the welding engineer and ASME or ASTM standards, it is necessary to test surface cracks and inside cracks using the non-destructive test (NDT) method, namely the dye penetrant test and radiography test, to determine the results of welding at pipe joints. In addition, it is also necessary to know the time and cost required for each method in the testing process. The results of the radiography test and penetrant test on carbon steel pipe welding joints showed porosity welding defects 1 mm long. Weld defects in duplex stainless steel pipes were not found. Then the results of the total testing time using the radiography test take 18% longer than testing using the penetrant test. Furthermore, the total costs that need to be incurred during the test are found to be 2~3 times more expensive than the cost of the penetrant test.

A novel procedure to determine the hoop mechanical properties of pipe materials using ring elongation testing technique

In this study, experiments including axial tensile tests and ring elongation tests, as well as analytical analyses were developed to determine the mechanical properties of ASTM A106 Grade B seamless carbon steel (A106-B) pipe material. Ring elongation tests were performed on the ring specimens to determine the mechanical properties of the A106-B pipe material in the hoop direction. Whereas axial tensile tests were carried out on standard axial tensile specimens to determine the axial stress-strain behavior of the A106-B pipe material. The axial stress-strain curve of the A106-B pipe material was used as a reference to validate the ring elongation test results. Besides, Analytical analyses using curved and straight beam formulas were developed. Directly from the ring elongation tests experimental results, both the curved and straight beam formulas accurately predicted the young's modulus and hoop yield strength of the A106-B pipe material. Moreover, the A106-B pipe material's plastic stress-strain behavior in the hoop direction was also successfully determined directly from the ring elongation test results with high accuracy.

塩化ビニル管の繰返し曲げ挙動

Many buildings have been reported to stop their service due to damage to non-structural members such as equipment piping after large-scale earthquakes. Although data on deformation capacity and strength of carbon steel pipe for ordinary piping is being collected, few studies are conducted on polyvinyl chloride pipes (PVC pipes) for drainage. Cyclic bending tests are conducted of PVC pipes with nominal diameters of 40A, 50A and 75A to evaluate their deformation capacity and strength. The result is that the deformation of PVC pipes is larger than that of steel pipes, and shows brittle failure.

Enabling the injection of hydrogen in high-pressure gas grids: Investigation of the impact on materials and equipment

Green hydrogen is a renewable gas that can help to reach the goal of decarbonizing the energy sector. The use of the natural gas grid for seasonal storage and transport of hydrogen needs previous assessment of its tolerance, ensuring safe and viable operation. In this work, the tolerance of the most typical material pipelines and key elements of high-pressure gas grids to the transport of 20 mol% hydrogen blends at 80 barg has been investigated at pilot scale. For this, the experimental campaign carried out at a testing platform replicating a high-pressure gas grid lasted 3000 h. The tightness of different kind of valves led to hydrogen losses below 1 Nml·h−1. No embrittlement or other kind of damage was found on these valves or the different parts of the equipment (regulator, flowmeter) tested. C-ring, 4pb and CT-WOL specimens have been prepared from carbon steel pipes (API5L Gr X42 to X70), showing no damage after exposure to hydrogen. H2/CH4 deblending has also been successfully achieved using Pd-based membrane technology, obtaining a high-purity separated streams.

ANALISIS PENGARUH ARUS PADA PENGELASAN BERTINGKAT (MULTILAYER WELDING) TERHADAP STRUKTUR MIKRO, KEKERASAN DAN KUAT TARIK SAMBUNGAN MATERIAL ASTM A106

This aims of this study to determine the effect of multilayer welding on ASTM A106 type carbon steel pipe material on the characteristics of the microstructure, hardness and maximum tensile strength of the material. ASTM A106 type carbon steel pipe is used as a raw material for welding using the Shielded Metal Arc Welding (SMAW) method. Welding on material joints is carried out in three layers (multilayer welding), namely the root pass, hot pass, and capping layers. There are two variations of welding specimens carried out in this study, namely in specimen 1 the currents used were 60, 70 and 80 A while in specimen 2 the currents used were 70, 80 and 90 A. To determine the effect of current variations on each specimen carried out three include Vickers Testing, microstructure testing and tensile testing. The results show that the base metal area is dominated by the ferrite phase, which indicates that the area has low hardness while the weld shows more perlite phase than ferrite besides the grain size is smaller and denser; this indicates that the hardness level will increase when compared to base metal. The results of the hardness test for all variations of the specimen concluded that the highest hardness value was in the weld. From the tensile test, it can be concluded that specimen 2 has a greater tensile strength of 2.5% when compared to specimen 1.

Leakage localization in an underground pressurized pipeline in steady-state

A new easy-to-implement approach based on low sampling rate sensors is proposed to estimate artificial leakage location in pressurized gas-filled pipelines. The proposed technique requires low sampling rate data and similar to some previous studies, acoustic sensors are localized on one side of the leakage. Previous studies have mainly placed sensors on both sides of the leakage which make it challenging to implement especially for long pipeline applications.This paper proposes a novel technique to localize artificial leakage in a buried and non-buried pipeline by implementing two simple electret microphones and attenuation analysis of recorded signals. An experimental set-up is conducted on a pressurized carbon steel pipe to validate the proposed method. The effects of pressure, orifice diameters and depth of specimen and sensor in the ground on the final result are discussed. The experimental results reveal the effectiveness of the proposed technique in low sampling rate data.

Developing two amino acid derivatives as high-efficient corrosion inhibitors for carbon steel in the CO2-containing environment

During the oil and gas exploitation, the corrosion of carbon steel pipes causes great economic loss, heavy casualties, environmental pollution, and waste of resources. The development of highly efficient and stable corrosion inhibitors is of great significance for the corrosion protection of carbon steel in oil and gas exploitation. L-cysteine is widespread in various plants (e.g. onion, cauliflower, and cabbage sprout). As a corrosion inhibitor, it usually has low inhibitive efficiency in most corrosive environment. Chemical modification is the most efficient method to solve this issue. Herein, two synthetic amino acid derivatives (2-phenylthiazolidine-4-carboxylic acid (PTCA) and 2-(thiophen-2-yl)thiazolidine-4-carboxylic acid (TTCA)) were investigated as high-efficient corrosion inhibitors to deal with the corrosion issue of carbon steel in the CO2-containing environment. The anti-corrosion property of the amino acid derivatives was investigated by electrochemical experiment, surface technique and theoretical calculations. The electrochemical results show that PTCA and TTCA present high corrosion inhibition efficiencies at the concentration of 0.8 mM: PTCA (99.1%) and TTCA (99.3%). The inhibitive mechanism of PTCA and TTCA on carbon steel surface is revealed by theoretical calculations. It is found that the PTCA and TTCA adsorb at the steel/solution interface by forming Fe-O bonds. Compared to PTCA, TTCA exhibits stronger adsorption on carbon steel surface by forming shorter Fe-O bonds with a more negative adsorption energy, which accounts for the better inhibitive performance of TTCA.

Simulations of hydrate reformation in the water production line of the second offshore methane hydrate production test in Japan’s Nankai trough

Natural gas hydrates are a potential new energy resource, however, challenges for stable, long-term gas hydrate production remain. This study examines the flow assurance risk of hydrate re-formation in production lines during gas hydrate production, which is a key issue in designing reliable production systems and operations. The focus of this study is the second offshore methane hydrate production test conducted in the Nankai trough area of Japan in 2017, where the depressurization method with a pump, wellbore gas separation, and two production lines for gas and water was applied. In this field test, separation inefficiencies caused significant quantities of gas to be produced from the water production line, posing a risk of hydrate re-formation. To understand and aid in management of this risk, we have developed models of hydrate growth and dissociation in water-dominant flow and conducted flow simulations that were compared to field data from the water production line in this field case. The simulation predictions suggest that the hydrate re-formation was not significant in this production test due to use of flexible hoses with a low overall heat transfer coefficient. The thermal insulation of the flexible hoses contained the heat generated by hydrate formation inside the production lines, resulting in a heat transfer limited system with low hydrate volume fractions (<5.2 vol%). Further simulations were conducted to estimate the sensitivity of such systems to insulation and materials choice, where a system with the flexible hoses replaced with carbon steel pipes was predicted to experience volume fractions four times greater (<19.8 vol%). Given hydrate production test systems typically take the form of short vertical lines, this indicates that pipe insulation may be critical in managing the risk of plugging due to re-formation. This insight is particularly important given the widespread use of carbon steels in subsea production facilities. Simulations enabled by the algorithm presented in this work will inform design choices for future methane hydrate production facilities. The use of thermal insulators will likely limit the degree of hydrate re-formation in such systems, and enable the deployment of management strategies that minimize or eliminate chemical injection.

Strength evaluation of support frame of the low level liquid effluent pipes of nuclear plant

Disposal of low level radioactive liquid effluents of nuclear plant into the sea is carried out through carbon steel pipes inside a guard pipe. The treated effluents are discharged inside the sea beyond breaker zone through two disposal pipes. The disposal pipe discharges the treated effluent to two numbers of 1 m diameter pipe which goes down till sea bed. This guard pipe should be supported on top of the jetty against wind, wave, and dead loads. This study is intended to cover the design adequacy and material selection of the liquid discharge piping support configuration. Material and coating requirements of the support frame is chosen after careful evaluation of the prevailing saline environment and economic consideration. Elastomeric bearing provides necessary support & firm adherence of the support arrangement to the erected pile cap. Elastomeric bearing are easy to install and offer low maintenance. The support frame is checked for dead load, pipe load, live load, wind load, wave ¤t loads, and seismic loads. Wave and current loads were calculated based on Morison semi empirical equation. Linear elastic structural analysis of the support frame was carried out. This article provides insight to the materials used in supporting this pipelines and the basis behind the material selection. After material selection, strength evaluation of the structure is elaborately carried out for all the loads. Indian standards and API recommended practice were adopted for the strength assessment of the structure. Support arrangement is formed using trusses at different levels, spandrel girders and hangers connecting the spandrel girders. All the stresses for structural arrangement for liquid discharge pipe support are checked and found within acceptable limits.

Use of waste to wealth process derived sustainable silica-rich graphene analogues to provide enhanced corrosion resistance properties for coatings on carbon steel, exposed to marine environments

Here, we have demonstrated the effects of the application of silica-rich green-graphene analogues (SRGA) mixed epoxy coating on carbon steel in terms of corrosion resistance and other properties. The anticorrosion performance of SRGA/EP coatings with various concentrations (0.05 wt%, 0.1 wt%, and 0.5 wt% SRGA) on carbon steel in 3.5 wt% NaCl was investigated using the potentiodynamic polarization technique (PDP) and electrochemical impedance spectroscopy (EIS). The surface morphologies of pure epoxy (EP) and SRGA/EP-coated specimens were investigated by scanning electron microscopy (SEM). Incorporating the SRGA/EP coating approach on carbon steel pipes can improve the thermal stability, hydrophobicity, and surface finish of the produced composite coatings. The corrosion inhibition efficiency of 0.1 wt% SRGA/EP-coated carbon steel specimens was 99 % higher than uncoated carbon steel specimens. The thermal stability of 0.1 wt% SRGA/EP coating was improved by 5–7 % compared to pure EP coating. The synthesized SRGA/EP coating showed acceptable uniform distribution on the carbon steel. The average roughness (Ra) of SRGA/EP-coated carbon steel was 67.8 % lower compared to the uncoated ones and 37.3 % lower than the pure EP-coated carbon steel specimens. These materials, derived from green processes can be suitable replacements for traditional toxic chemicals employed for corrosion-resistant coating in carbon steel surfaces of water pipes. Apart from the benefits of use in performance, SRGA application can help environmental -social-governance (ESG) compliance for the paints and coatings industry.

Experimental and theoretical studies on the lateral collapse of mechanically lined pipes

The mechanically lined pipe, which consists of a thin non-corrosive liner and a carbon steel pipe, is an economical way to transport acidic fluid in offshore applications. However, it is prone to lateral loading and potentially develops plastic collapse and liner separation during the operational stage. The present study examines its crushing performance using small-scale 2-inch lined pipes manufactured by a customized hydroforming facility. The lined pipes comprised a seamless GB45 carbon steel tube and a grade T2 copper liner. Four ring specimens extracted from lined pipes and two single-layer rings were crushed on a universal testing machine in a quasi-static manner. The tube was found to develop an ovalized shape initially and then changed into a "∞" shape in the end. The carrier and liner were found to stay together throughout the crushing process, with slight liner separation taking place. The manufacture and lateral collapse processes were also reproduced with finite element models and nonlinear analytical formulation. The analytical model was established based on the principle of virtual work and nonlinear ring theory, assuming small strain and finite rotation. It showed that the analytical and numerical simulation results agreed with the experimental results. The influence of major parameters of the problem was also studied based on the full-scale lined pipe. Amongst other findings, manufacture-related plastic hardening is shown to affect the load-carrying capacity and the growth of separation during lateral collapse.