51,523 research outputs found

    A lean assessment tool based on systems dynamics

    Get PDF
    Lean manufacturing is synonymous with a set of practices used in the identification and elimination of waste related with the manufacturing system, and focusing on what creates value for the customer. Lean assessment tools enable an overall audit of the performance of lean practices, and so are able to identify lean improvements. The interactions between lean practices and their improvements are often latent and need to be investigated: a systems approach can be used to disclose these hidden interactions. In this article, system dynamics is used as a lean assessment tool to assess and improve lean performance for a print packaging manufacturing system

    Machining strategy development in 5-axis milling operations using process models

    Get PDF
    Increased productivity and part quality can be achieved by selecting machining strategies and conditions properly. At one extreme very high speed and feed rate with small depth of cut can be used for high productivity whereas deep cuts accompanied with slow speeds and feeds may also provide increased material removal rates in some cases. In this study, it is shown that process models are useful tools to simulate and compare alternative strategies for machining of a part. 5-axis milling of turbine engine compressors made out of titanium alloys is used as the case study where strategies such as flank milling (deep cuts), point milling (light cuts) and stripe milling (medium depths) are compared in terms of process time by considering chatter stability, surface finish and tool deflections

    A framework for smart production-logistics systems based on CPS and industrial IoT

    Get PDF
    Industrial Internet of Things (IIoT) has received increasing attention from both academia and industry. However, several challenges including excessively long waiting time and a serious waste of energy still exist in the IIoT-based integration between production and logistics in job shops. To address these challenges, a framework depicting the mechanism and methodology of smart production-logistics systems is proposed to implement intelligent modeling of key manufacturing resources and investigate self-organizing configuration mechanisms. A data-driven model based on analytical target cascading is developed to implement the self-organizing configuration. A case study based on a Chinese engine manufacturer is presented to validate the feasibility and evaluate the performance of the proposed framework and the developed method. The results show that the manufacturing time and the energy consumption are reduced and the computing time is reasonable. This paper potentially enables manufacturers to deploy IIoT-based applications and improve the efficiency of production-logistics systems

    Special Session on Industry 4.0

    Get PDF
    No abstract available

    Sustainable machining - correlation of the optimization by minimum energy, minimum manufacturing time and cost of production

    Get PDF
    The machining process leads the indices of productivity and employability in a world level and has an enormous influence at social and economics standards, however it requires machinery that consume high levels of energy, chemical fluids and has great emissions of greenhouse gases. In our days as governments and clients increase their demands for the degradation of ecosystems, also increase the need for companies to implement sustainable policies and improve their environmental performances. The reduction of energy consumption and consequently the reduction of fossil supplies are a major source of concern at this level. This article establish a bridge between the classical approaches of optimization models of machining processes (Maximizing Production Rate and Minimizing Production Cost), and reduction of electricity. For a single pass turning it was used a mathematical model to analyse the data taken as a reference, optimizing the critical parameters of consumption of time, money and energy

    Ensuring the reliability and performance criterias of crankshafts

    Get PDF
    The issues of efficiency improvement of manufacturing crankshafts in order to ensure their reliability and performance criteria are the priorities in modern production of internal combustion engines. Using the capabilities of modern special grinding machines can improve the quality of machining and obtain the necessary running characteristics of crankshafts. In work the questions connected with development of a method of calculation of rigidity of crankshafts for increase of accuracy of their machining, reliability and performance criteria’s are considered. Based on the proposed methodology, numerical calculations have performed and the possibility of determining the deflections and crankshafts rigidity in any section have been justified. The original construction of the following grinding steady rest for CNC grinding machines specified for machining the crankshaft main bearing journal and connecting rod journal is proposed. The construction design of the device allows for compensating the influence of the cutting force on the elastic strain of the part, depending on the change in its rigidity. The practical value of the research includes in develop recommendations for determining the optimal parameters for the round infeed grinding cycle of the crank pins from the point of view of productivity and accuracy
    corecore