The use of an MES in the company depends less on the size of the com-pany or the particular industry but rather on the production structure (shop production, production segments, assembly line/flow production, etc.) and the type of production (non-repetitive production, one-off and small-series production, quantity production, mass production). While the main reason for using an MES in the case of multistage shop production (turning shop, milling shop, electroplating shop, etc.) is to improve the interplay between the individual processing steps and thus the passage of the order through production, the emphasis in the case of mass production is certainly on increasing the degree of utilization of individual production lines. Due to its modular structure, MES can be easily adapted to the specific production environment and its task demands. Within the context of a planned MES project it is therefore important to first ascertain what initial situation (pro-duction structure and type) applies. The second step should be to find out how production planning and control is currently being carried out and how this could be expanded by MES functionalities.
1.6.2 Technical requirements
The technical incorporation of an MES system in the company requires a corporate network (LAN) with which the management level, production management and production itself can intercommunicate. In this way MES servers and clients can be integrated into the corporate network. Data ex-change with higher-level planning systems (ERP, PPS, etc.) takes place via standardized interfaces. Information on the production level is acquired ei-ther manually (machine operator at data terminals) or automatically by ma-chine connections via mama-chine interfaces (for example, OPC, Euromap, etc.).
1.6.3 Economic efficiency Process capability
Alongside product quality many companies have recognized process quality as offering further potential for greater operational efficiency in production.
In an examination of economic efficiency, the first step should be to define which process-oriented objectives are to be achieved by the use of an MES.
Goals of this kind could be, for example, a reduction in the lead time, an increase in machine utilization, an improvement in delivery reliability,
1.6 Use of an MES system in the company 35 a reduction in work in progress inventories or a reduction in defect costs.
On the basis of the objectives which have been defined it will be possible to investigate in concrete terms the potential for economic improvement. Ex-amples of potentials of this kind include:
Increasing machine utilization
In the metal-working industry the average machine utilization is often lower than assumed but planning and calculations are actually based on a higher assumed utilization. Systematic recording and evaluation of all instances of unscheduled downtime with the aid of an MES system helps to reveal the causes of downtime, remove them, and thus considerably improve machine utilization. The investment costs of an MES here only amount to a few percent of annual machine costs. In other words, even an improvement in machine utilization of just a few percent will deliver the return-on-investment (ROI) desired.
Reducing the lead time
Reduction in lead times is without doubt the most important factor in eco-nomic efficiency in production. Connected with the order lead time are delivery time (competitive advantage), delivery reliability (customer satis-faction), inventory (liquidity) and throughput (profits). Using an MES system makes it possible to recognize these potentials and exploit them systematically.
These simple examples show what process potentials can be hidden in a company and how they can be uncovered with the pragmatically applied software tool MES alone. Generally speaking, potential for improvement in the company can be picked up more quickly due to the MES-based process transparency and also exploited more quickly due to the MES-based control cycles. Furthermore, since all process data are acquired sys-tematically, it is possible to detect more potential for improvement than without an MES.
1.6.4 Support for CIP and current certifications
Although there is still huge potential hidden in the improvement of process quality and although the continuous improvement process (CIP) is anchored in the current certification standards, such as DIN EN ISO 9001:2000 or ISO/TS 16949:2002, in many companies process orientation is not actually implemented in practice. A frequent reason for this is a lack of process transparency, although this situation can easily be remedied by using an
36 1 New ways for the effective factory
MES. Due to the integration between the ERP system on the one hand and the production level on the other, an MES is continuously acquiring data for most process influences (orders, machines, tools, personnel, material, qual-ity, etc.) in production. This means that hit lists (Pareto diagrams) relating to the most frequent causes of problems and errors can be drawn up, process times determined (setup times and processing times, waiting times and downtimes, interruptions due to faults, etc.) and key data relating to process and product quality calculated and displayed (for example, the OEE index, machine utilization, degree of processing, scrap rate, etc.). In this way an MES system supports improvement activities in all phases: define (defini-tion of processes to be improved), measure (measure process data), analyze (analysis of measured data) and control (check steps taken).
Fig. 1.15. Faster detection and exploitation of improvement potential with the aid of an MES
1.6.5 Definition and tracking of objectives
Manufacturing scorecard: process-oriented key data
To be able to even survive in an ever fiercer competitive environment, many companies depend on an entirely specific competitive strategy, such as price leadership, technological leadership, service level, flexibility and so on. With the aid of the manufacturing scorecard method and proceeding
1.7 Practical examples of potential benefits 37