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Article
Publication date: 14 February 2019

Weishan Huang, Jing-Li Luo, Hani Henein and Josiah Jordan

This paper aims to evaluate the sulfide stress cracking (SSC) resistance of L80 casing steels with different alloying chemistries (e.g. Ti-B and Mn-Cr-Mo) by correlating the…

Abstract

Purpose

This paper aims to evaluate the sulfide stress cracking (SSC) resistance of L80 casing steels with different alloying chemistries (e.g. Ti-B and Mn-Cr-Mo) by correlating the reduction in area ratio with the mechanical property, inclusion and carbide.

Design/methodology/approach

SSC tests were conducted in 5.0 Wt.% sodium chloride and 0.5 Wt.% acetic acid solution saturated with H2S using constant load tensile method. The microstructure and fracture morphology of the steel were observed using scanning electron microscope. The inclusion and carbide were identified by energy dispersive spectroscopy and auger electron microscope.

Findings

Among all the testing steels, electric resistance welding (ERW) L80-0.5Mo steel demonstrates the highest SSC resistance because of its appropriate mechanical properties, uniform microstructure and low inclusion content. The SSC resistance of L80 steels generally decreases with the rising yield strength. The fracture mode of steel with low SSC resistance is jointly dominated by transgranular and intergranular cracking, whereas that with high SSC resistance is mainly transgranular cracking. SSC is more sensitive to inclusions than carbides because the cracks are easier to be initiated from the elongated inclusions and oversized oxide inclusions, especially the inclusion clusters. Unlike the elongated carbide, globular carbide in the steel can reduce the negative effect on the SSC resistance. Especially, a uniform microstructure with fine globular carbides favors a significant improvement in SSC resistance through precluding the cracking propagation.

Originality/value

The paper provides the new insights into the improvement in SSC resistance of L80 casing steel for its application in H2S environment through optimizing its alloying compositions and microstructure.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 January 2016

Wei Yan, Yong Xiang, Wenliang Li and Jingen Deng

This paper aims to establish the downhole CO2 partial pressure profile calculating method and then to make an economical oil country tubular goods (OCTG) anti-corrosion design. CO2

Abstract

Purpose

This paper aims to establish the downhole CO2 partial pressure profile calculating method and then to make an economical oil country tubular goods (OCTG) anti-corrosion design. CO2 partial pressure is the most important parameter to the oil and gas corrosion research for these wells which contain sweet gas of CO2. However, till now, there has not been a recognized method for calculating this important value. Especially in oil well, CO2 partial pressure calculation seems more complicated. Based on Dolton partial pressure law and oil gas separation process, CO2 partial pressure profile calculating method in oil well is proposed. A case study was presented according to the new method, and two kinds of corrosion environment were determined. An experimental research was conducted on N80, 3Cr-L80 and 13Cr-L80 material. Based on the test results, 3Cr-L80 was recommended for downhole tubing. Combined with the field application practice, 3Cr-L80 was proved as a safety and economy anti-corrosion tubing material in this oil field. A proper corrosion parameter (mainly refers to CO2 partial pressure and temperature) can ensure a safety and economy downhole tubing anti-corrosion design.

Design/methodology/approach

Based on Dolton partial pressure law and oil gas separation process, CO2 partial pressure profile calculating method in oil well is proposed. An experimental research was conducted on N80, 3Cr-L80 and 13Cr-L80 material. A field application practice was used.

Findings

It is necessary to calculate the CO2 partial pressure properly to ensure a safety and economy downhole tubing (or casing) anti-corrosion design.

Originality/value

The gas and oil separation theory and corrosion theory are combined together to give a useful method in downhole tubing anti-corrosion design method.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 17 May 2023

Abbas Rezaeian, Mona Mansoori and Amin Khajehdezfuly

Top-seat angle connection is known as one of the usual uncomplicated beam-to-column joints used in steel structures. This article investigates the fire performance of welded…

Abstract

Purpose

Top-seat angle connection is known as one of the usual uncomplicated beam-to-column joints used in steel structures. This article investigates the fire performance of welded top-seat angle connections.

Design/methodology/approach

A finite element (FE) model, including nonlinear contact interactions, high-temperature properties of steel, and material and geometric nonlinearities was created for accomplishing the fire performance analysis. The FE model was verified by comparing its simulation results with test data. Using the verified model, 24 steel-framed top-seat angle connection assemblies are modeled. Parametric studies were performed employing the verified FE model to study the influence of critical factors on the performance of steel beams and their welded angle joints.

Findings

The results obtained from the parametric studies illustrate that decreasing the gap size and the top angle size and increasing the top angles thickness affect fire behavior of top-seat angle joints and decrease the beam deflection by about 16% at temperatures beyond 570 °C. Also, the fire-resistance rating of the beam with seat angle stiffener increases about 15%, compared to those with and without the web stiffener. The failure of the beam happens when the deflections become more than span/30 at temperatures beyond 576 °C. Results also show that load type, load ratio and axial stiffness levels significantly control the fire performance of the beam with top-seat angle connections in semi-rigid steel frames.

Originality/value

Development of design methodologies for these joints and connected beam in fire conditions is delayed by current building codes due to the lack of adequate understanding of fire behavior of steel beams with welded top-seat angle connections.

Details

Journal of Structural Fire Engineering, vol. 15 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 14 May 2020

Subhradip Mukherjee, R. Kumar and Siddhanta Borah

The purpose of this work is to propose quad wheel robot with path navigation using an intelligent novel algorithm named as obstacle-avoiding intelligent algorithm (OAIA).

Abstract

Purpose

The purpose of this work is to propose quad wheel robot with path navigation using an intelligent novel algorithm named as obstacle-avoiding intelligent algorithm (OAIA).

Design/methodology/approach

The paper proposes OAIA algorithm, which is used to minimize the path distance and elapsed time between source and goal.

Findings

The hardware implementation of the Quad Wheel Robot design includes a global positioning system (GPS) module for path navigation. An ultrasonic module (HC SR04) is mainly used as the sensing unit for the system. In the proposed scheme, the GPS locator (L80) is used to obtain the current location of the robot, and the ultrasonic sensor is utilized to avoid the obstacles. An ARM processor serves as the heart of the Quad Wheel Robot.

Practical implications

This paper includes real-time implementation of quad wheel robot for various coordinate values, and the movement of the robot is captured and analysed.

Originality/value

The proposed OAIA is capable of estimating the mobile robot position exactly under ideal circumstances. Simulation and hardware implementation are carried out to evaluate the performance of the proposed system.

Details

International Journal of Intelligent Unmanned Systems, vol. 9 no. 1
Type: Research Article
ISSN: 2049-6427

Keywords

Article
Publication date: 29 June 2010

C. Miranda‐Herrera, I. Sauceda, J. González‐Sánchez and N. Acuña

The purpose of this paper is to evaluate the electrochemical behaviour of two carbon steels exposed to acidic geothermal solutions and their resistance to hydrogen induced…

Abstract

Purpose

The purpose of this paper is to evaluate the electrochemical behaviour of two carbon steels exposed to acidic geothermal solutions and their resistance to hydrogen induced cracking (HIC), in order to determine the effect of hydrogen damage on the failure process of the steels used for line pipe and casings at a geothermal plant.

Design/methodology/approach

Samples of two different steels: ASTM A‐53 Grade B (line pipe) and API L‐80 (casing) were immersed for a duration of 96 h in the electrolyte proposed by NACE to evaluate susceptibility to HIC. Samples of the two steels embedded in non‐conducting Bakelite were subjected to potentiodynamic polarisation scans at room temperature using as the electrolyte brines obtained from different wells at the Cerro Prieto geothermal plant. Hardness tests were performed on the samples before and after the HIC tests in order to determine hardness changes induced by hydrogen penetration as field results indicated embrittlement of the steels after four months of service.

Findings

The steels, ASTM A‐53 Grade B and API L‐80 did not exhibit crack sensitivity as no cracks are observed in the tests specimens, though they showed an increase in hardness. The steels exhibited high‐corrosion rates in the brine media at room temperature (3.3 mm/yr), which is expected to increase at higher temperatures.

Originality/value

The work revealed that carbon steels used for line pipes and casings at geothermal plants can exhibit high resistance to HIC, however they corrode at high rates and may show embrittlement. It is suggested that due to the high‐operation temperature, the damage induced by hydrogen resulted in hardness increase but was not sufficient to develop cracks.

Details

Anti-Corrosion Methods and Materials, vol. 57 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 March 1986

A new heat pump system, developed by Forward Ultrasonics and sister company KLN of Germany, is being used in the Fultra range of ultrasonic, free‐standing, two‐stage cleaning…

Abstract

A new heat pump system, developed by Forward Ultrasonics and sister company KLN of Germany, is being used in the Fultra range of ultrasonic, free‐standing, two‐stage cleaning machines. This not only gives large reductions in unit cost but improves the machine's efficiency which considerably reduces running costs.

Details

Circuit World, vol. 12 no. 4
Type: Research Article
ISSN: 0305-6120

Book part
Publication date: 26 March 2024

Manpreet Kaur and Shivani Malhan

Purpose: Manufacturing has always been considered a backbone for economic growth. It has been considered an imperative sector in the growth of an economy. This study aims to trace…

Abstract

Purpose: Manufacturing has always been considered a backbone for economic growth. It has been considered an imperative sector in the growth of an economy. This study aims to trace the long-term relationship between gross domestic product (GDP) and manufacturing sector in the context of Indian economy.

Need for the study: According to research, the significance of the manufacturing sector is waning over time. This chapter studies the long-term relationship between the GDP, an indicator of growth, and the manufacturing sector. Over the last few decades, the contribution of manufacturing has been stagnant in the GDP of India.

Methodology: The decadal growth of various sectors in the GDP of India is studied using time series analysis. This study used the data released by the Ministry of Statistics and Programme Implementation (MOSPI) from 1950–1951 to 2013–2014. The long-term relationship between the sector of manufacturing and the GDP is examined through the augmented Dicky–Fuller (ADF) test and auto-regressive distributed lag (ARDL) models.

Findings: The findings suggest that in the Indian scenario, there is no relationship for an extended period between the GDP and the manufacturing sector, which calls for further policy implications.

Practical implications: India, while having the world’s fastest-growing economy, must continue to take steps to attain high growth rates and long-term sustainability by reducing obstacles to the expansion of the service sector in addition to manufacturing. Manufacturing-led services are to be boosted through policy interventions.

Details

The Framework for Resilient Industry: A Holistic Approach for Developing Economies
Type: Book
ISBN: 978-1-83753-735-8

Keywords

Article
Publication date: 7 July 2022

Subhradip Mukherjee, R. Kumar and Siddhanta Borah

This paper aims to incorporate one intelligent particle swarm optimization (IPSO) controller to realize an optimum path in unknown environments. In this paper, the fitness…

Abstract

Purpose

This paper aims to incorporate one intelligent particle swarm optimization (IPSO) controller to realize an optimum path in unknown environments. In this paper, the fitness function of IPSO is designed with intelligent design parameters, solving the path navigation problem of an autonomous wheeled robot towards the target point by avoiding obstacles in any unknown environment.

Design/methodology/approach

This controller depends on randomly oriented positions with all other position information and a fitness function. Evaluating the position’s best values, this study gets the local best values, and finally, the global best value is updated as the current value after comparing the local best values.

Findings

The path navigation of the proposed controller has been compared with particle swarm optimization algorithm, BAT algorithm, flower pollination algorithm, invasive weed algorithm and genetic algorithm in multiple challenging environments. The proposed controller shows the percent deviation in path length near 14.54% and the percent deviation in travel time near 4% after the simulation. IPSO is applied to optimize said parameters for path navigation of the wheeled robot in different simulation environments.

Originality/value

A hardware model with a 32-bit ARM board interfaced with a global positioning system (GPS) module, an ultrasonic module and ZigBee wireless communication module is designed to implement IPSO. In real-time, the IPSO controller shows the percent deviation in path length near 9%.

Details

Industrial Robot: the international journal of robotics research and application, vol. 50 no. 1
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 March 1990

J.C. VERITE

Problem 8 of the TEAM workshop comes from non‐destructive testing. A differential probe moves above a block with a crack. Three experimental and four numerical results are…

Abstract

Problem 8 of the TEAM workshop comes from non‐destructive testing. A differential probe moves above a block with a crack. Three experimental and four numerical results are presented and analysed. Some specific difficulties arising in this problem are discussed.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 9 no. 3
Type: Research Article
ISSN: 0332-1649

Open Access
Article
Publication date: 10 June 2020

Javier Solano, Segundo Camino-Mogro and Grace Armijos-Bravo

Banks are institutions that inject money in the economy and help to boost it when there are problems in some markets, especially in productive sectors. In this way, analysing the…

1666

Abstract

Purpose

Banks are institutions that inject money in the economy and help to boost it when there are problems in some markets, especially in productive sectors. In this way, analysing the competition in this sector is an important tool for policymakers as non-competitive behaviour could affect the financial system and economy. The purpose of this paper is to measure the degree of competition in the Ecuadorian private banking sector divided by size, from 2000 to 2015, using panel data collected by the official regulator institution.

Design/methodology/approach

The authors applied the model proposed by Panzar and Rosse (1987) and its H-statistic using a reduced price and revenue equation estimated by pooled ordinary least squares, fixed effects, random effects, feasible generalised fixed effects and panel correction standard errors (PCSE).

Findings

The authors show that given the presence of some problems in data such as heteroskedasticity and autocorrelation, the most appropriate technique is PCSE. The authors also found robust evidence supporting that large banks compete in a monopolistic market, small and medium-sized banks operate in monopolistic competition, and Ecuadorian small, medium-sized and large banks stay in long-run equilibrium.

Originality/value

This paper contributes to the actual literature of competition degree in two ways. First, different from traditional papers, we do not control by size; so, we divided the analysis by size, because in Ecuador and also in many developing countries, bank’s competition is different for each group of size because the levels of liquidity, risk and other indicators are different from one group to another. Second, we show the robustness of the results using a scaled and unscaled equation, using many controls and using five methods to contrast the competition degree.

Details

Journal of Economics, Finance and Administrative Science, vol. 25 no. 50
Type: Research Article
ISSN: 2077-1886

Keywords

1 – 10 of 43