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To ensure the reliable and safe operation of elevated-temperature pipes and equipment in the long term, it is essential to thoroughly assess the creep rupture life. Nevertheless, there is currently no design code that specifies a creep rupture life evaluation method for non-nuclear elevated-temperature equipment. The paper aims to discuss this issue.

An analysis was conducted to compare the differences and conservativeness in calculating creep strain using three major codes (ASME-CC-2843, API-579 and BS-7910) based on the results of the 316H creep constitutive model and creep strain prediction. In addition, the creep resistances of 316H, 304H and 347H were compared. Subsequently, the ANSYS Usercreep subroutine was developed to compare the discrepancies between different codes under multiaxial stress conditions using numerical simulations.

BS-7910 employs the Norton creep model with calculation parameters for the average creep strain rate, which is not applicable for the engineering design stage. ASME-CC2843 code primarily focuses on the primary and secondary creep stages, making it more suitable for non-nuclear pipeline and equipment design. For 316H, the creep strain curves predicted by ASME-CC2843 and API-579 typically intersect at a specific point. By combining the creep strain predicted by ASME-CC2843 and API-579, 347H exhibits superior predicted creep resistance compared to 316H, whereas 316H exhibited better predicted creep resistance than 304H.

This study provides a guide for future evaluation methods and material choices for non-nuclear equipment and pipelines operating at elevated temperatures.

The overall goal of this chapter is twofold. First, the authors aim to identify indigenous phenomena that influence employee turnover and retention in the Chinese context. Second, the authors link these phenomena to the contextualization of job embeddedness theory. To achieve the goal, the authors begin by introducing three macro-level forces (i.e., political, economic, and cultural forces) in China that help scholars analyze contextual issues in turnover studies. The authors then provide findings in the literature research on employee retention studies published in Chinese academic journals. Next, the authors discuss six indigenous phenomena (i.e., hukou, community in China, migrant workers, state-owned companies, family benefit prioritization, and guanxi) under the three macro-level forces and offer exploratory propositions illustrating how these phenomena contribute to understanding employee retention in China. Finally, the authors offer suggestions on how contextualized turnover studies shall be conducted in China.

The purpose of this study is to investigate the characteristic and function of oxide film formed on grinding wheel in electrolytic in-process dressing (ELID) precision grinding and improve the quality of ELID grinding.

Dynamic film forming experiments were carried out with a simulation device close to the actual processing conditions. Then, the ELID grinding experiments of bearing rings were performed using grinding wheels with good film forming effect. The experiment was designed by quadratic regression general rotation combination method. The influence of grinding depth, electrolytic voltage, duty cycle and grinding wheel linear speed on grinding effect is analyzed.

A mathematical model for the formation rate of oxide film was established. The experiments show that the composition of grinding wheel and grinding fluid, as well as the electrical parameters, influence the film forming effect. Thus, the oxide film plays an important role in ELID grinding.

This study provides a reference for the design and selection of grinding wheel and grinding fluid and the setting of process parameters in ELID grinding.

The nonlinear friction disturbance of the moving joint surface of the feed system can lead to the residual vibration of the system, prolong the stability time of the system and reduce the motion precision and machining precision of the machine tool. This paper aims to concern the vibration between joint surfaces caused by nonlinear friction.

The model is established from the micro and macro scale based on the LuGre model. The friction characteristics of the moving joint surface are explored. The friction experiment of GCr15 pin and 45 steel disk is designed and the influence of lubrication condition, speed, acceleration and normal load on friction characteristics are studied.

Among the drive speed, damping and stiffness, the negative gradient effect of friction, which is characterized by the difference of static and dynamic friction coefficient Δµ, is the main cause of friction vibration between moving joint surfaces. Sufficient lubrication, a proper increase of speed and acceleration, a reasonable reduction of normal load can reduce the negative gradient effect, which can weaken the vibration caused by the nonlinear friction and improve the friction characteristics of the moving joint surface.

In the past studies, more attention has been paid to revealing the relationship between the relative speed and friction, while the acceleration is often ignored. The negative gradient effect of friction is improved in this paper by changing the contact conditions. Research findings of this paper effectively improve the friction characteristics of the moving interface and provide the basis for restraining the nonlinear vibration between the moving interfaces.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0476/

The purpose of this study is to understand the current trends and development of corporate social responsibility (CSR) reporting in emerging and developing economies and analyze 106 Chinese central enterprises (CEs) that disclose CSR reports from 2004 to 2015.

This study analyzes all the CSR reports available to the public from CEs between 2004 and 2015 in China. This paper carefully examines the reporting patterns and standards in those CSR reports. CEs in China are focused on because state-owned companies account for a large proportion of the Chinese stock market because of their social and economic institutional characteristics.

The results in this paper confirm a growth trend in the numbers of CSR reports, as predicted. The results also suggest that the number of CSR reports from the CEs containing some assurance has dramatically increased. However, the findings indicate that the current content of the CSR reports may not fully meet the needs of users of information from different industries, regions and interests, as more than 20 CEs have formulated their own CSR framework. The lack of unified, sustainable reporting and assurance may reduce the comparability and effectiveness of CSR reporting.

This study provides evidence of the trends and development of CSR reporting in China.

The findings extend the understanding of CSR reporting by analyzing Chinese CE data. The results also provide decision-useful information for the government and other policymakers when considering CSR reporting and assurance standards.

This paper presents a developed spatial-temporal analysis framework for the case of investigating the business performance of construction consultancy services (CCS) in China.

The spatial-temporal analysis is based on the data envelopment analysis (DEA) technique. The spatial analysis follows the DEA results under a contemporaneous benchmark technology and a virtual decision-making unit, consisting of ranking analysis, cluster analysis and variation analysis. The temporal analysis is reliant on the DEA results under a global benchmark technology and the time value of money, including trend analysis and driving force analysis containing pure technical and scale efficiency factors.

Three CCS types in China are investigated, including engineering survey and design, construction supervision and procurement agency. The performance rank order and cluster classifications are mainly related to economic development levels. Engineering survey and design demonstrates the best performance and higher imbalances; however, construction supervision and procurement agency illustrate lower performance and imbalances. Scale efficiency significantly promotes business performance, whereas pure technical efficiency plays an inconspicuous role.

The CCS promote technical efficiency by developing their service and innovation levels. The service of engineering survey and design registered in Beijing, Shanghai and Guangdong is recommended for entering the service market in China.

The spatial-temporal analysis framework was developed, which is generic and provides a pathway to measure, compare and assess performance comprehensively. The CCS business performance is firstly measured.

The serious friction caused by the fluctuation of friction occurs when start-up and will reduce the positioning accuracy of the servo axes of high precision machine tools, the purpose of this paper is to study the friction fluctuation characteristics of friction coefficients between interfaces under different working conditions.

HT200 and 45# materials were experimentally studied by friction and wear testing machine UMT-3, the variation of friction coefficient under different working conditions (different start-up conditions, the variation of lubrication state area and different roughness) were measured.

The results show that the larger start-up acceleration shortens the pre-sliding time of the interface friction, makes the friction coefficient decrease faster, reduces the mixed lubrication area of the contact surface and makes the contact surface reach the stable lubrication state quickly. It can be concluded that the larger roughness surface will lead to the larger mixed lubrication area, the larger static friction coefficient and the larger drop between static and dynamic friction coefficient and easy to cause friction vibration.

The results reveal the friction fluctuation rule of the metal interface during the different start-up process, which is of guiding significance to reveal the lubrication principle and mechanism of the mechanical interface.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0482/

The purpose of this study is to characterize the galvanic corrosion behavior of a simulated X80 pipeline steel welded joint (PSWJ) reconstructed by the wire beam electrode (WBE) and numerical simulation methods.

The galvanic corrosion of an X80 PSWJ was studied using WBE and numerical simulation methods. The microstructures of the coarse-grained heat affected zone, fine-grained heat affected zone and intercritical heat affected zone were simulated in X80 pipeline steel via Gleeble thermomechanical simulation processing.

Comparing the corrosion current density of coupled and isolated weld metal (WM), base metal (BM) and heat-affected zone (HAZ), the coupled WM exhibited a higher corrosion current density than isolated WM; the coupled BM and HAZ exhibited lower corrosion current densities than isolated BM and HAZ. The results exhibited that the maximum anodic galvanic current fitted the Gumbel distribution. Moreover, the numerical simulation results agreed well with the experimental data.

This study provides insight into corrosion evaluation of heterogeneous welded joints by a combination of experiment and simulation. The method of reconstruction of the welded joint has been proven to be a feasible approach for studying the corrosion behavior of the X80 PSWJ with high spatial resolution.

Inadequate support stiffness leads to motor vibrations exceeding the standard during the commissioning process. However, in-depth research on the parameters affecting bearing support stiffness remains incomplete. This paper aims to reveal the impact of the bearing support stiffness on the shaft system and explore the bearing assembly factors affecting the bearing support stiffness and optimization.

The finite-element method is adopted to calculate the bearing support stiffness accurately, with model validation conducted via a test rig. The significant factors affecting bearing housing stiffness are investigated by using the orthogonal experiment method. Finally, a multi-objective optimization strategy for bearing assembly parameters is proposed to improve the bearing support stiffness.

The bearing housing stiffness is anisotropic in vertical and horizontal directions, influencing the dynamics of shaft system. Bearing housing looseness can significantly reduce the bearing support stiffness. The contact angle and interference have a very significant effect on the bearing housing stiffness. Preferred combinations of bearing assembly parameters can be obtained by multi-objective genetic algorithms.

This study proposed a test determination method of bearing housing stiffness, showed that the phenomenon of bearing housing loosening in the test will reduce the bearing support stiffness and considered the respective phase anisotropy of the bearing housing stiffness. The influence of bearing support stiffness on the dynamic characteristics of the shaft system was studied, alongside the optimization of bearing assembly parameters affecting housing stiffness.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2024-0265/

The purpose of this paper is to explore the dimensionality of intragroup conflict and to develop an instrument with acceptable psychometric properties for the comprehensive measurement of conflict.

This paper strictly follows the standard scale-developing method: first, establish theoretical dimensions of intragroup conflict; then, develop the initial scale through in-depth interviews and coding schemes; third, revise and verify the scale through exploratory factor analysis and confirmatory factor analysis; and, finally, examine the predictive validity of the new intragroup conflict scale.

This study identifies four dimensions of intragroup conflict – cognitive conflict, affective conflict, behavioral conflict, and interest-based conflict – and provides evidence of construct validity for a new measure. The results show that cognitive and interest-based conflict affect group innovation performance positively, whereas affective and behavioral conflict affects it negatively.

This study first detects interest-based conflict as a new dimension and explores a more comprehensive scale (ABCI) that reflects all the connotations of conflict, which deepens the understanding of intragroup conflict, laying a solid foundation for empirical studies of conflict.