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Article
Publication date: 1 June 2004

73

Abstract

Details

Circuit World, vol. 30 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 June 2003

Don Y. Lee

SKF Group is one of the largest bearing manufacturers in the world, well known for its innovations and high quality bearings. One of its innovations is the CARB bearing

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Abstract

SKF Group is one of the largest bearing manufacturers in the world, well known for its innovations and high quality bearings. One of its innovations is the CARB bearing, which functions particularly well under severe working conditions where traditional bearings break down easily. Compared to traditional bearings, CARB saves costs and creates value because it requires less maintenance, has a longer life, and simplifies machine structure. SKF launched CARB in 1995 and acquired a patent for a period of ten years. CARB bearings, which are manufactured in Sweden, have been widely used in Western markets and become almost standard parts. SKF started to export the new bearings to China in 1997. CARB bearing markets, in China, could be classified into two parts, the new installation (OEM) market and maintenance market, which mainly consisted of the replacement of the CARB bearing for the Chinese‐made conventional bearings on numerous machines. The SKF Shanghai Office was in charge of devising a marketing strategy to sell the CARB bearings to the maintenance markets, the majority of which were large‐scale state‐run companies. But the China market is huge, culture and influences from the West vary across regions, styles of doing business are also different. The first task of the SKF Shanghai Office was to segment the maintenance market and select the segment which was least difficult to enter.

Details

Journal of Business & Industrial Marketing, vol. 18 no. 3
Type: Research Article
ISSN: 0885-8624

Keywords

Article
Publication date: 10 August 2018

Xibing Li, Weixiang Li, Xueyong Chen, Ming Li, Huayun Chen and Xin Yue

The purpose of this paper is to examine the effect of application of a heat pipe in an aspect of hydrostatic thrust bearings on thermal balance and deformation and the…

Abstract

Purpose

The purpose of this paper is to examine the effect of application of a heat pipe in an aspect of hydrostatic thrust bearings on thermal balance and deformation and the role of this application in increasing the rotating speed of a workbench.

Design/methodology/approach

Numerical simulations of oil film temperature field, the temperature field and thermal deformation of the bearing’s workbench and base were performed by finite element analysis (FEA) software for both the traditional hydrostatic thrust bearings and the heat pipe ones.

Findings

Oil pad and workbench of the hydrostatic thrust bearings are fabricated with a heat pipe cooling structure, which can take away most of the heat generated by shearing of the oil film, control the temperature rise and thermal deformation of the hydrostatic thrust bearing effectively, avoid the dry friction phenomenon and finally improve the processing quality of equipment.

Originality/value

The heat pipe hydrostatic thrust bearings could control the temperature rise and thermal deformation of the hydrostatic thrust bearing effectively, avoid the dry friction phenomenon and improve the processing quality of equipment.

Details

Industrial Lubrication and Tribology, vol. 70 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 14 June 2022

Cuicui Chen, Qian Yang, Qingan Chen, Yanhui Wang, Dong Xu, Hezong Li, Xiliang Zhang, Christopher M. Harvey and Jiwei Liu

This study aims to investigate the effects of graphite-MoS2 composite solid lubricant on the tribological properties of copper-based bearing materials under dry conditions.

Abstract

Purpose

This study aims to investigate the effects of graphite-MoS2 composite solid lubricant on the tribological properties of copper-based bearing materials under dry conditions.

Design/methodology/approach

The mixture of Graphite-MoS2 was inlaid in ZQSn6-6–3 tin bronze and ZQAl9-4 aluminum bronze matrix. These copper-embedded self-lubricating bearing materials were considered in friction pairs with 2Cr13 stainless steel, and their tribological properties were studied by using an MM200 wear test machine.

Findings

The results show that the friction coefficients and wear rates of copper-embedded self-lubricating bearing materials are lower than those of the ordinary copper-based bearing materials. The wear performance of the tin bronze inlaid self-lubricating bearing material is better than that of the aluminum bronze inlaid self-lubricating bearing material. The wear mechanism of the tin bronze bearing material is mainly adhesive wear, and that of the aluminum bronze bearing material is mainly grinding wear, oxidation wear and adhesive wear. The copper-embedded self-lubricating bearing materials had no obvious abrasion, whereas the aluminum bronze inlaid self-lubricating bearing material exhibited deep furrows and obvious abrasion under high loads.

Originality/value

These results are helpful for the application of copper-embedded self-lubricating bearing materials.

Details

Industrial Lubrication and Tribology, vol. 74 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 27 November 2018

Mubing Yu, Xiaodong Yu, Xuhang Zheng, Hang Qu, Tengfei Yuan and Daige Li

This paper aims to describe a theoretical and experimental research concerning influence of recess shape on comprehensive lubrication performance of high speed and heavy…

Abstract

Purpose

This paper aims to describe a theoretical and experimental research concerning influence of recess shape on comprehensive lubrication performance of high speed and heavy load hydrostatic thrust bearing with a constant flow.

Design/methodology/approach

The lubrication performance of a hydrostatic thrust bearing with different recess shape under the working conditions of high speed and heavy load has been simulated by using computational fluid dynamics and finite volume method.

Findings

It is found that the comprehensive lubrication performance of a hydrostatic thrust bearing with circular recess is optimal. The results demonstrate that recess shape has a great influence on the lubrication performance of the hydrostatic thrust bearing.

Originality/value

The simulation results indicate that to get an improved performance from a hydrostatic thrust bearing with constant flow, a proper selection of the recess shape is essential.

Article
Publication date: 10 July 2017

Xibing Li, Tian Cheng, Ming Li, Mingjian Li, Ruren Wu and Yingsi Wan

The purpose of this study with the rapid development of the heavy/large mechanical equipment, the heavy computer numerical control (CNC) vertical lathe has become the…

Abstract

Purpose

The purpose of this study with the rapid development of the heavy/large mechanical equipment, the heavy computer numerical control (CNC) vertical lathe has become the ideal processing equipment for the parts of those mechanical equipments. The main factor which affects the machining quality and efficiency of heavy CNC vertical lathe is the mechanical properties of the hydrostatic thrust bearing.

Design/methodology/approach

This paper did the research based on the large size sector oil pad’s lubrication performance of the hydrostatic thrust bearing in the heavy/large equipments, establishing the lubrication performance distribution mathematical model of the velocity field, flow field, pressure field and so on, analyzing the bearing behavior of the large size sector oil pad.

Findings

The results show that the oil flow generated by the plate relative motion will be greater than that generated by the pressure difference in area B, with the rotational speed’s increasing of the hydrostatic thrust bearing, and the direction is opposite. The oil flow generated by the centrifugal force will be greater than that generated by the pressure difference in area C, with the rotational speed’s increasing of the hydrostatic thrust bearing, and the direction is opposite. When the rotational speed of the hydrostatic thrust bearing is too high, the friction heat will be not easy to be sent out. The bearing rotating speed should be lower than the comparatively smaller one of ω1 and ω2, which can help avoid the rise of too high temperature.

Originality/value

The research provides powerful theoretical foundation for practical application of the large size sector oil pad hydrostatic thrust bearing, its structure design and operating reliability, realizing the lubrication performance prediction of the large size hydrostatic thrust bearing.

Details

Industrial Lubrication and Tribology, vol. 69 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 15 September 2022

Zhiyong Wang, Yuankai Zhou and Xue Zuo

The purpose of this paper is to study the tribological effect of zinc borate ultrafine powder (ZBUP) oil additive on the running-in quality.

Abstract

Purpose

The purpose of this paper is to study the tribological effect of zinc borate ultrafine powder (ZBUP) oil additive on the running-in quality.

Design/methodology/approach

The running-in quality was assessed by friction coefficient and surface topography. Fractal parameters including fractal dimension, the width of multifractal, the multifractal difference, multifractal parameters, phase trajectory and correlation dimension were used to extract the nonlinear characteristics of surface topography and friction coefficient.

Findings

When the ZBUP additive was added, the convergence degree of the phase trajectory and the stability of the running in were higher than that of base oil. It indicates that the ZBUP additive can improve the running-in quality of sliding bearing. Besides, the ZBUP additive can shorten the running-in time. A boundary protective film, which has good friction-reducing and anti-wear effects, was generated on the surface when the ZBUP additive was added.

Originality/value

The results have a great significance to improve the running-in quality and prolong the service life of the sliding bearing.

Details

Industrial Lubrication and Tribology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 5 September 2016

Jing Hu, Yuan Zhang, Maogen GE, Mingzhou Liu, Liu Conghu and Xiaoqiao Wang

The optimal control on reassembly (remanufacturing assembly) error is one of the key technologies to guarantee the assembly precision of remanufactured product. However…

Abstract

Purpose

The optimal control on reassembly (remanufacturing assembly) error is one of the key technologies to guarantee the assembly precision of remanufactured product. However, because of the uncertainty existing in remanufactured parts, it is difficult to control assembly error during reassembly process. Based on the state space model, this paper aims to propose the optimal control method on reassembly precision to solve this problem.

Design/methodology/approach

Initially, to ensure the assembly precision of a remanufactured car engine, this paper puts forward an optimal control method on assembly precision for a remanufactured car engine based on the state space model. This method takes assembly workstation operation and remanufactured part attribute as the input vector reassembly status as the state vector and assembly precision as the output vector. Then, the compensation function of reassembly workstation operation input vector is calculated to direct the optimization of the reassembly process. Finally, a case study of a certain remanufactured car engine crankshaft is constructed to verify the feasibility and effectiveness of the method proposed.

Findings

The optimal control method on reassembly precision is an effective technology in improving the quality of the remanufactured crankshaft. The average qualified rate of the remanufactured crankshaft increased from 83.05 to 90.97 per cent as shown in the case study.

Originality/value

The optimal control method on the reassembly precision based on the state space model is available to control the assembly precision, thus enhancing the core competitiveness of the remanufacturing enterprises.

Details

Assembly Automation, vol. 36 no. 4
Type: Research Article
ISSN: 0144-5154

Keywords

Book part
Publication date: 10 September 2018

Christiane Prange and Youzhen Zhao

The authors of this chapter investigate internationalisation strategies of small and medium-sized companies (SMEs) in China. We highlight the specific challenges that…

Abstract

The authors of this chapter investigate internationalisation strategies of small and medium-sized companies (SMEs) in China. We highlight the specific challenges that Chinese SMEs encounter when selecting international country markets in terms of distance and entry speed. The authors adopt an ambidexterity perspective that differs from traditional explanations of internationalisation behaviour by highlighting the need to balance seemingly disparate options for international expansion. Three cases provide an illustration of how Chinese companies combine distant with proximate market entries and slow with accelerated entry speed. The authors highlight how these strategies can drive and enhance international aspirations of Chinese SMEs.

Details

Key Success Factors of SME Internationalisation: A Cross-Country Perspective
Type: Book
ISBN: 978-1-78754-277-8

Keywords

Article
Publication date: 28 October 2013

John Sanders and Laura Galloway

The purpose of this paper is to investigate website quality in rural firms in four countries, by using Gonzalez and Palacios's Web Assessment Index (WAI). There is an…

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Abstract

Purpose

The purpose of this paper is to investigate website quality in rural firms in four countries, by using Gonzalez and Palacios's Web Assessment Index (WAI). There is an assertion in the literature that quality is lower amongst rural firms than urban firms, and lower amongst small firms than large firms. The disadvantages of lack of access to skills and economic peripherality in rural areas are attributed to this. Concurrently, there is reason to surmise that the websites of firms in transition economies may be higher quality than those in market economies. The paper aims to explore websites in distinct rural regions to investigate if variation occurs.

Design/methodology/approach

To evaluate website quality the WAI was applied to a sample of 60 rural firms representing 15 each in Scotland, New Zealand, Southern Russia and Hunan Province in China. Analysis of the categorical data was performed using a variety of established methods.

Findings

The WAI is of use in terms of website quality management. Additionally, comparisons between the quality of websites in the sample of small rural firms with those of large firms in previous studies support the contention that large firms generally have better quality websites. Results also illustrate that there are some differences in website quality between rural small businesses in the different locations. In particular, small rural firms in Hunan Province in China had websites of observable better quality than those elsewhere. The authors conclude that skills, knowledge and infrastructure have a bearing on the sophistication of small firms' websites.

Research limitations/implications

Implications include that variation in the rural economy by region prevails as the rural economy is not, as often implied, a homogeneous concept.

Practical implications

There are implications in terms of exploring the effects of regulation, culture and infrastructure on rural small to medium-sized enterprises (SMEs). The internet may indeed contribute to rural economies, but only insofar as it is facilitated by infrastructure and access to skills, and by culture and perceived usefulness by business owners.

Originality/value

The paper contributes to the understanding of rural entrepreneurship as a heterogeneous concept by comparing practice in four distinct rural regions. It also adds weight to the emerging identification of exogenous factors as being at least as much a factor in determining the use of ICT in rural SMEs as endogenous motivations, skills and resources.

Details

Journal of Small Business and Enterprise Development, vol. 20 no. 4
Type: Research Article
ISSN: 1462-6004

Keywords

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