Problem
Centrotherm Photovoltaics AG is a global supplier of technology and equipment for the photovoltaics, semiconductor, and microelectronics industries. Specifically, they needed to:
- Determine the type and amount of equipment needed to satisfy the manufacturing capacity they were planning.
- Evaluate different layout alternatives to improve the throughput and utilization rate.
- Inspect possible bottlenecks in the material flow.
- Evaluate operator behavior impact on the factory output.
- Test the consequences of maintenance within various time frames.
- Identify system behavior in case of breakdowns.
- Identify scrap probability.
- Evaluate change of performance during planned downtimes.
The ACP-IT consultants used AnyLogic simulation software to evaluate the manufacturing optimization possibilities.
Solution
Manufacturing Optimization — Model Logic
Using AnyLogic Professional’s ability to create and save custom object libraries, the consultants encapsulated their vast simulation experience in the photovoltaic and semiconductor manufacturing industries and created their own libraries, which they reused in many manufacturing optimization projects, including this one. These libraries featured elements built on top of the AnyLogic model development environment and allowed the consultants to easily model different kinds of equipment, material handling systems inside factories, personnel, and production control systems, all specific to the photovoltaic and semiconductor industries. In the Centrotherm project, this solution helped modelers quickly reproduce various aspects of the client’s manufacturing system behavior with simulation.
Once the manufacturing optimization model was built, the experimentation phase of the project began. The consultants tested many parameters to find the best solutions.
The input data, that included layout configurations and various parameters, was taken directly from Excel and Access files. Each simulation run reproduced one year of factory operation.
Read also: Simulation Modeling for Consulting, a white paper that provides many insights on designing and optimizing a network layout, production scheduling, etc.
First, the consultants experimented with the overall production line design, using parameter variation and optimization. They tested many parameters; including those concerning manufacturing capacity and the number of various pieces of equipment, cassettes, bins, etc., to see which configurations would work best in terms of throughput, reliability, and scrap rate.
Then the consultants worked to optimize transportation policies, buffer zone allocation, and watermark control processes. Some of the proposed layout variants were rejected during this stage due to their poor performance.
Finally, they tested the resulting few manufacturing optimization solutions manually to investigate the benefits and drawbacks of each one, and to find out how they could be further improved.
Outcome
The proposed solutions provided Centrotherm Photovoltaics AG with the opportunity to significantly improve the production line design and choose the best solution in terms of manufacturing optimization: throughput, reliability, and scrap rate at a low cost.
Additionally, at the end of the project, the model was released to the client so that it could be used for analysis of future change in the factory. The manufacturing optimization model allows the customer to carry out their own experiments, playing with parameters and layout, changing input data, etc. This manufacturing facility simulation model will serve as a decision-support tool at the factory for a long period of time.
