FIAT participating in the AMICE project has applied CIMOSA model engineering in a gearbox assembly plant analysis (see Figure 13).
This application includes the global modelling of the FIAT logistics processes for ordering parts and products (gearboxes) as well as the material flow control in the parts manufacturing-assembly-warehouse environment. Modelling the different processes in the Gearbox Manufacturing Domain has allowed to simulate different logistics scenarios and to analyse and evaluate the results in terms of throughput and turn-around time. Starting with Kanban and Push-Type production control, the optimum solution is a combination of both Push-Type in the purchasing and parts manufacturing areas and Pull Type in the gearbox assembly shop.
The CIMOSA Modelling Framework and Modelling Paradigms have been used to perform the modelling of this FIAT production system with the purpose of giving answers to the following three questions :
The experience of utilisation of CIMOSA Concepts applying the ARTIFEX (*) tool to model a real environment has evidenced the following Business Values of CIMOSA :
The integration of the Views allowed by CIMOSA has brought enhancement of the quality of the analysis with respect to previous modelling practices regarding the Information, Resources and Organisational descriptions. A comparison among the lead-times and efforts required in the past to model a productivity system and the lead times and costs to model the same system, in a "coteris paribus" situation, using re-usability of step-wise derived models has yielded a reduction factor of 3 times in the time to build ex-novo a model and a reduction factor of 8 time to adapt a model to a similar plant have been experienced.
As part of the ESPRIT Project VOICE (Validating OSA in Industrial CIM Environments by Integration and Implementation), the German machine tool builder TRAUB has implemented and validated a CIMOSA prototype for the re-engineering of their manufacturing operation. The main objectives were to achieve shorter delivery times, higher flexibility and improved communication between the design, planning and manufacturing department.
This has been achieved by modelling the domains of order and planning, tool management and order execution with the help of GT VOICE, the CIMOSA modelling tool developed in EP VOICE.
Two major results have been derived from the model :
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The implemented production management and control system comprises an area controller, (shown in Fig. 14) several cell control units and a tool consign workplace. Transparent communication and information access has been achieved from area level down to NC controllers through the information and communication services of the CIMOSA Integrating Infrastructure, utilising ISO standard MMS for process control and monitoring. |
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The major benefits for TRAUB have been,
Some concerns have been reported. namely a considerable learning effort and the complexity of the CIMOSA documentation at this point in time.
The second application in a medium size paper manufacturer is concerned with re-engineering of the whole operation through modelling, simulation and model enactment of benchmarks. It is implemented at the German SME company KOEHLER and was developed with the Engineering School Offenburg and the Institute of Applied Computer Science at the Research Centre Karlsruhe. Manufacturing and the follow on pre-processing of various paper types of many customer specific paper variants requires the mastering of very complex manufacturing processes. The different process steps are dependent on each other which means for the production planning to think and plan capacity and schedules in network structures rather than in simple task sequences. Therefore the transparency of the individual business processes of the total manufacturing process is an significant requirement for the economic manufacturing of such products. These processes have to take into account ecological parameters as well since recycling of natural resources like water and air are becoming more and more valuable.
Therefore the problem of production planning is the requirement of large volume production for the basic paper and the ever increasing demand for small lots of pre-processing for the customer specific variants. Figure 15 provides an overview of the manufacturing operation. The major concern in this company was the huge amount of work-in-process which lead to additional storage capacity requirement. Modelling and analysis of order flow and work flow indicated bottlenecks created by to many internal orders due to batch size splitting, etc.
In order to get a full analysis of the production system an economic evaluation was added providing an Economic View on the CIMOSA model. Using benchmarks for all entities in the model processes, resources, manufacturing and customer orders as well as products enabled this economic evaluation. The results revealed a significant influence of the pre-production functions (production planning, marketing and sales) on the economics of the manufacturing process. Especially the issuing of small lot sizes orders with high priorities had contributed to the dramatic increase in work-in process and the need for additional storage capacity.
Benefits for the company have been the elimination of the need for a new warehouse and the acceptance of models for providing much better transparency of the impact of a particular high priority order on the total manufacturing process.
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www-cimosa@cnt.pl, 2.03.1996 (last update: 02.03.1996)
