Small and medium-sized enterprises (SMEs) represent an important component of the economy in both developed and developing countries. Nowadays, the competitive industrial environment is encouraging these companies to redesign their manufacturing practices. Lean manufacturing (LM) has been widely implemented in several industries and has been shown to have had a positive impact on the performance and development of companies. This review aims to examine this impact on the performance of manufacturing companies, to emphasize the recent progress of LM amongst SMEs worldwide, and to show that most successful LM initiatives are those implemented in SMEs and large companies. However, very small businesses (VSBs) are struggling to introduce LM into their management systems. A new approach has been developed to establish a new lean implementation framework that could be adapted to the specific context of VSBs.

No abstract

No abstract

Purpose This study aims to present a numerical model to investigate cavitation effects on oscillatory porous squeeze film. This effect is able to cause considerable damage to the lubrication mechanisms, mainly in the form of surface erosion. The erosion process is caused by surface spalling due to alternating positive and negative contact stresses imposed by bubble collapse. If the process continues uncontrolled, the performance of the contact will rapidly deteriorate. Design/methodology/approach The study is conducted numerically using Elrod–Adams model for the modified Reynolds equation coupled with the Darcy’s law for the lubricant flow through the porous medium. The governing equations are numerically discretized and iteratively solved. Findings The numerical results show that frequency, amplitude and permeability have a significant influence on the generation of cavitation. A comparison of the present numerical results against available literature experimental data in particular case proved a good agreement. Originality/value The present paper is to develop a more realistic and efficient model. Indeed, the consideration of cavitation phenomena in this model will lead to a more accurate prediction of the squeeze film characteristics. The results of this paper are based on original work and have practical value.

The dynamic loading in hydrodynamic bearings and squeeze film dampers submits the lubricant film to periodical squeeze actions. These solicitations have an effect on the film load-carrying capacity and can lead to its rupture (cavitation). In the present experimental study, we achieve a quantitative measure of the effect of geometric and kinematic parameters of the non-conforming contact on the hydrodynamic load-carrying capacity. On the designed test rig, the contact geometry, the average film thickness, the oscillations amplitude and frequency can be varied. The measured load-carrying capacity is compared to numerical predictions. The numerical results are in good agreement with the experimental data. Several oil film rupture modes have been observed. Each mode depends on the oscillations frequency, the oil bath height in the tank and the surface geometry.