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Article
Publication date: 25 August 2022

Hangjun Zhang, Jinhui Fang, Jianhua Wei, Huan Yu and Qiang Zhang

This paper aims to present an adaptive sliding mode control (ASMC) for tunnel boring machine cutterhead telescopic system with uncertainties to achieve a high-precision…

Abstract

Purpose

This paper aims to present an adaptive sliding mode control (ASMC) for tunnel boring machine cutterhead telescopic system with uncertainties to achieve a high-precision trajectory in complex strata. This method could be applied to solve the problems caused by linear and nonlinear model uncertainties.

Design/methodology/approach

First, an integral-type sliding surface is defined to reduce the static tracking error. Second, a projection type adaptation law is designed to approximate the linear and nonlinear redefined parameters of the electrohydraulic system. Third, a nonlinear robust term with a continuous approximation function is presented for handling load force uncertainty and reducing sliding mode chattering. Moreover, Lyapunov theory is applied to guarantee the stability of the closed-loop system. Finally, the effectiveness of the proposed controller is proved by comparative experiments on a scaled test rig.

Findings

The linear and nonlinear model uncertainties lead to large variations in the dynamics of the mechanism and the tracking error. To achieve precise position tracking, an adaptation law was integrated into the sliding mode control which compensated for model uncertainties. Besides, the inherent sliding mode chattering was reduced by a continuous approximation function, while load force uncertainty was solved by a nonlinear robust feedback. Therefore, a novel ASMC for tunnel boring machine cutterhead telescopic system with uncertainties can improve its tracking precision and reduce the sliding mode chattering.

Originality/value

To the best of the authors’ knowledge, the ASMC is proposed for the first time to control the tunnel boring machine cutterhead telescopic system with uncertainties. The presented control is effective not only in control accuracy but also in parameter uncertainty.

Details

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

Keywords

Article
Publication date: 24 January 2020

Guiyang Wu, Qiang Zhang and Nange Zhang

Organic coatings are one of the most widely applied methods for corrosion protection of metallic materials such as the tubing used in sour gas field. However, such…

Abstract

Purpose

Organic coatings are one of the most widely applied methods for corrosion protection of metallic materials such as the tubing used in sour gas field. However, such coatings usually encounter the risk of failure due to the harsh and complex environment. Therefore, the study of failure of the organic coating is highly significant.

Design/methodology/approach

In this paper, the effects of Cl-concentration, HCl content, hydrogen sulfide/carbon dioxide (H2S/CO2), temperature and flow rate on the failure of epoxy-phenolic coating on the internal surface of BG90S steel tubing were investigated using adhesion force measurement, metallographic microscope, electrochemistry impedance spectroscopy and Fourier transform infrared spectroscopy.

Findings

The results show that the Cl-concentration, HCl content and H2S/CO2 do not affect the failure process too much as the ion concentration increased. However, the flow rate at the high temperature is the most important factor affecting the corrosion resistance of the inner coating tubing. With the increase of the flow rate, the pore resistance of the coating shows a decreasing trend, and the rate of decrease in pore resistance is first rapid and then slow. It demonstrates that the penetration speed of the electrolyte solution into the coating varied from fast to slowly. A weakening influence of the flow rate on the penetration failure of the inner coating can be found as the increase of the flow rate. Once the HS-ions penetrate through the coating and reach at the coating/steel interface where H2 could be formed through the adsorption reaction, the coating failure occurs.

Originality/value

The failure of the coating depends on the penetration rate of water and ions, with the presence of exposed or punctured holes is accelerated and HS- was adsorpted by substrate Fe, and form H2 molecules between the coatings and substrate, that results failure of coatings.

Details

Pigment & Resin Technology, vol. 49 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Content available
Article
Publication date: 7 December 2020

Zhihua Zhang, Qiang Zhang and Muhammad Jawed Iqbal

366

Abstract

Details

International Journal of Climate Change Strategies and Management, vol. 12 no. 5
Type: Research Article
ISSN: 1756-8692

Article
Publication date: 24 March 2022

Ya-Peng Jia, Wan-Chang Sun, Yan Xiao, Jing-Pei Liu, Cong-Xiao Zhang, Tong-Qiang Zhang and Ze-Feng Hou

This paper aims to research the effect of different concentrations for Nd(NO3)3 and Ce(NO3)3 on the microstructures and corrosion resistance of Ni-W-P composite coatings…

Abstract

Purpose

This paper aims to research the effect of different concentrations for Nd(NO3)3 and Ce(NO3)3 on the microstructures and corrosion resistance of Ni-W-P composite coatings through electroless plating method.

Design/methodology/approach

Scanning electron microscope, attached energy dispersive spectroscopy system and X-ray diffraction were used in this work. Meanwhile, the immersion test and electrochemical tests were used to characterize the corrosion behavior of the coating.

Findings

The coatings prepared at 1.00 g·L−1 Nd(NO3)3 exhibit a dense structure and high phosphorus content (12.38 wt.%). In addition, compared to the addition of Ce(NO3)3, when Nd(NO3)3 was introduced at a concentration of 1.00 g·L−1, the minimum corrosion rate of the coating was 1.209 g·m−2·h−1, with a noble Ecorr (−0.29 V) and lower Icorr (8.29 × 10−4 A·cm−2).

Originality/value

The effects of rare earths on the deposition and corrosion resistance mechanisms of Ni-W-P composite coatings were explored, with the rare earth elements promoting the deposition of nickel and tungsten atoms. Simultaneously, the amorphization of the coating increases, which excellently enhances the corrosion resistance of the coating.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 24 March 2019

Xiaoxue Liu, Yahui Zhang, Suming Xie, Qiang Zhang and Hanfei Guo

The car body stiffness of express freight sliding side covered wagon decreased for the sliding and the resonance vibration based on the flexible car body has affected the…

Abstract

Purpose

The car body stiffness of express freight sliding side covered wagon decreased for the sliding and the resonance vibration based on the flexible car body has affected the dynamics performances. Dynamic loading will cause fatigue cracks and eventually lead to fatigue failure of the car body. This paper aims to investigate the influence of car body flexibility on the evaluation of the failure.

Design/methodology/approach

In this paper, the railway vehicles random analysis procedure (RVRAP) is employed to study the fatigue failure of the rigid-flexibility model. Following the analysis process, the rigid-flexibility model is established and four contrastive schemes for simulation analysis are designed. To verify the results, an experimental test using the real car body structure on the vibration test plant is carried out; the RMS of dynamic stress is obtained and compared with the simulation results.

Findings

The results show that the flexibility of the car body has a crucial influence on the fatigue life.

Originality/value

The reliability is verified regarding the use of RVRAP at an appropriate stage on the antifatigue design of the vehicle.

Details

International Journal of Structural Integrity, vol. 12 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

Content available
Article
Publication date: 7 September 2021

Ziqiang Han, Marla Petal and Qiang Zhang

156

Abstract

Details

Disaster Prevention and Management: An International Journal, vol. 30 no. 3
Type: Research Article
ISSN: 0965-3562

Article
Publication date: 13 May 2022

Qiang Zhang, Zijian Ye, Siyu Shao, Tianlin Niu and Yuwei Zhao

The current studies on remaining useful life (RUL) prediction mainly rely on convolutional neural networks (CNNs) and long short-term memories (LSTMs) and do not take full…

Abstract

Purpose

The current studies on remaining useful life (RUL) prediction mainly rely on convolutional neural networks (CNNs) and long short-term memories (LSTMs) and do not take full advantage of the attention mechanism, resulting in lack of prediction accuracy. To further improve the performance of the above models, this study aims to propose a novel end-to-end RUL prediction framework, called convolutional recurrent attention network (CRAN) to achieve high accuracy.

Design/methodology/approach

The proposed CRAN is a CNN-LSTM-based model that effectively combines the powerful feature extraction ability of CNN and sequential processing capability of LSTM. The channel attention mechanism, spatial attention mechanism and LSTM attention mechanism are incorporated in CRAN, assigning different attention coefficients to CNN and LSTM. First, features of the bearing vibration data are extracted from both time and frequency domain. Next, the training and testing set are constructed. Then, the CRAN is trained offline using the training set. Finally, online RUL estimation is performed by applying data from the testing set to the trained CRAN.

Findings

CNN-LSTM-based models have higher RUL prediction accuracy than CNN-based and LSTM-based models. Using a combination of max pooling and average pooling can reduce the loss of feature information, and in addition, the structure of the serial attention mechanism is superior to the parallel attention structure. Comparing the proposed CRAN with six different state-of-the-art methods, for the predicted results of two testing bearings, the proposed CRAN has an average reduction in the root mean square error of 57.07/80.25%, an average reduction in the mean absolute error of 62.27/85.87% and an average improvement in score of 12.65/6.57%.

Originality/value

This article provides a novel end-to-end rolling bearing RUL prediction framework, which can provide a reference for the formulation of bearing maintenance programs in the industry.

Details

Assembly Automation, vol. 42 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 5 December 2018

Lin Liu, Hongyu Su, Xue Li, Yanan Wang, Qiang Zhang and Jianhua Qian

This paper aims to evaluate the inhibitive effect and adsorption behavior of the 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A) on copper in 3 per cent NaCl solution.

Abstract

Purpose

This paper aims to evaluate the inhibitive effect and adsorption behavior of the 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A) on copper in 3 per cent NaCl solution.

Design/methodology/approach

A thiazole Schiff bases were synthesized, named, 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A), which was fabricated respectively on copper surface by the molecular self-assembled. Evaluation was carried out by electrochemical measurement and surface analysis techniques. Measurement of static friction coefficient scanning electron microscopy and Contact angle analysis were applied, and it is finally confirmed the existence of the adsorbed film. The inhibitive mechanism of A was evaluated by means of quantitative calculation and molecular dynamics simulation.

Findings

The electrochemical measurement indicated that the self-assembled molecular film can effectively inhibit the corrosion of copper sheet, when the concentration was 15 mmol⋅L−1 and the assembly time was 6 h, the corrosion inhibition effect was the best, reaching as high as 97.5 per cent. Scanning electron microscopy results showed that the Schiff base compound forms a protective film on the surface of the copper, which effectively blocks the transfer of corrosion particles to the metal substrate, thereby inhibiting the occurrence of corrosion. Adsorption behavior of A followed the Langmuir’s adsorption isotherm and attributed to mixed-type adsorption. The results of Quantitative calculation and molecular dynamics simulation showed that A was adsorbed on Cu (111) surface in parallel.

Research limitations/implications

In this study, the corrosion inhibition properties of Schiff base film were investigated by combining theory with experiment. Theoretical calculation is helpful to guide the synthesis of efficient and environmentally friendly corrosion inhibitors.

Practical implications

The damage caused by metal corrosion is great. The self-assembled Schiff base membrane synthesized in this paper is simple and compact, and the corrosion inhibition efficiency of copper in 3 per cent NaCl solution is 97.5 per cent.

Social implications

Inhibition of metal corrosion can better save energy and reduce economic losses.

Originality/value

The synthesized Schiff base was prepared on the copper surface by the molecular self-assembled. The Schiff base membrane has a good corrosion inhibition effect on copper in 3 per cent NaCl solution, and the corrosion inhibition efficiency is up to 97.5 per cent.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 26 June 2018

Lin Liu, Hongyu Su, Jinjuan Xing, Dan Peng, Qiang Zhang and Jianhua Qian

This paper aims to evaluate the inhibitive effect and adsorption behavior of 5-(ethylthio)-1H-tetrazole (EHT) and 5-(benzylthio)-1H-tetrazole (BHT) on copper in a…

Abstract

Purpose

This paper aims to evaluate the inhibitive effect and adsorption behavior of 5-(ethylthio)-1H-tetrazole (EHT) and 5-(benzylthio)-1H-tetrazole (BHT) on copper in a sulfur-ethanol system.

Design Methodology Approach

Evaluation was carried out using electrochemical measurement and surface analysis techniques. Measurements of static friction coefficient by scanning electron microscopy and contact angle analysis were applied and finally confirmed the existence of the adsorbed film. The inhibitive mechanism of the two compounds was evaluated by means of quantitative calculation and molecular dynamics simulation. The friction coefficient of corrosion surface before and after adding corrosion inhibitor was determined through static friction coefficient measurements.

Findings

The electrochemical measurement indicated that the most effective concentration of two corrosion inhibitors was 70 mg L–1, while the inhibition efficiency of that was EHT > BHT. The friction coefficient data showed that the addition of corrosion inhibitor reduced the roughness of the corrosion surface. Adsorption behavior of two inhibitors followed the Langmuir’s adsorption isotherm and was attributed to mixed-type adsorption. The results of quantitative calculation and molecular dynamics simulation showed that tetrazole rings of the two inhibitors and its connected S atoms were adsorbed on Cu(111) surface in parallel.

Originality Value

The corrosion inhibition performance of two tetrazolium derivatives in a sulfur-ethanol system was studied by combining experiments with theory, which provided a theoretical basis for the future research.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 12 February 2020

Sang Xiong, Jia Si, Jianlin Sun, Hao Wu, Hongchen Dong and Chao Zhang

Corrosion inhibitors for copper immersed in emulsion were investigated by experiments and theoretical calculations, and this study aims to propose a new inhibition…

Abstract

Purpose

Corrosion inhibitors for copper immersed in emulsion were investigated by experiments and theoretical calculations, and this study aims to propose a new inhibition mechanism of the inhibitors having protective effects for copper corrosion.

Design/methodology/approach

Adsorption behavior of penta-heterocycles (thiophene, 1,2,5-oxadiazole, furan, 2 H-1,2,3-triazole, pyrrole and 1,2,5-thiadiazole) as corrosion inhibitors for copper immersed in oil-in-water (O/W) emulsions was investigated by weight loss, electrochemical tests, morphological characterization and theoretical calculations.

Findings

The orders of inhibition effect are furan < pyrrole < thiophene < 1,2,5-oxadiazole < 2H-1,2,3-triazole < 1,2,5-thiadiazole, and 1,2,5-thiadiazole at 0.5 mM has the best inhibition effect for copper immersed in emulsion. The results of scanning probe microscope, scanning electron microscope and electrochemical test show that a protective barrier can be formed on the surface of copper substrate with six corrosion inhibitors, thus effectively inhibiting the corrosion of copper mainly through chemisorption and following Langmuir’s adsorption isotherm.

Originality/value

Quantum chemical and molecular dynamic simulations demonstrate that all these compounds attached to Cu matrix with a flat-adsorption mode to prevent the emulsion corrode copper. Adsorbed inhibitors act as a barrier at Cu matrix to block corrosion and improve hydrophobicity.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

1 – 10 of 637