Case studies

A case study: Automated assembly equipment for metal housings of injection moulded plastic parts

Automated insertion of metal bushings directly into the injection press

Research: Radovan Petrík (MECASYS), Pavol Gužík (MECASYS Design Labs), Jozef Vnenčák - MECASYS CAM Program

Summary

MECASYS specializes in the development and implementation of automated solutions that improve the efficiency and accuracy of manufacturing processes. In this case study, we describe how we designed and built a specialized assembly machine for AAH Plastics that automated the insertion of metal bushings (bushings) directly into an injection molding press. The aim of this project was to ensure high assembly accuracy and process repeatability, minimising human error and optimising mass production. This solution demonstrates MECASYS' ability to deliver integrated automation systems for complex manufacturing challenges.

Description of the problem

AAH Plastics needed to develop, design and implement an assembly device directly into an injection moulding machine to automate the assembly of metal bushings into a plastic part. Previous methods, likely manual or less precise, had led to inconsistent results or low efficiency, affecting the quality of the final plastic components. The challenge was to ensure accurate and reliable insertion of the metal bushings during the injection molding process to avoid errors and slippage in production.

To increase the information value and manage the process more efficiently, it is advisable to track some key performance indicators (KPIs) to help optimise assembly and product quality:

- First Pass Yield (FPY) - measures the percentage of parts assembled correctly on the first try without the need for repairs, thus showing the accuracy and reliability of the assembly of metal bushings.

- Defects Per Unit (DPU) and Scrap Rate - track the number of defects and scrapped parts that affect the quality of final components.

- Overall Equipment Effectiveness (OEE) - evaluates the availability, performance and quality of equipment, providing a comprehensive view of the efficiency of an injection molding press with assembly equipment.

- Machine Downtime Rate - measures machine downtime that can negatively impact production continuity and productivity.

- Production Cycle Time - records the time it takes to produce one part, including assembly, which helps to optimise production speed and capacity.

- On-time Delivery (OTD) - tracks the percentage of orders delivered on time, which is an indicator of the reliability and stability of the production process.

By implementing these KPIs into the equipment, it will be possible to more accurately monitor and control the automated metal bushing assembly process, improve the quality of the final plastic parts, minimize errors and downtime, while improving overall production efficiency.

Solution

MECASYS approached the problem comprehensively, starting with a detailed analysis of the client's requirements and the injection molding machine environment. Subsequently, a 3D design of the machine was developed using SolidWorks software, where mechanical properties were simulated and ergonomics and integration were optimized.

The production of components was carried out on MECASYS multi-axis CNC machining centres, with the key element being the cutting-edge technology of 5-axis milling on HERMLE machines, which enable exceptional precision and surface quality to be achieved. This technology ensures the production of even the most demanding parts with high complexity and minimal tolerances.

The accuracy of production is then verified on modern CMM measuring machines from the renowned manufacturer Hexagon, which guarantees high reliability and quality of the resulting components. The equipment has been designed with an emphasis on robustness, reliability and easy integration into the client's existing production environment.

A significant competitive advantage of MECASYS is also the flexible and open communication with the client throughout the development process, which enables quick response to requirements and optimization of the solution according to the current needs.

Results and benefits

By implementing automated assembly equipment, AAH Plastics has achieved significant improvements in the quality, efficiency and reliability of the assembly of metal bushings into plastic parts.

Key benefits include:

1. High accuracy and consistency of assembly - Automation of the process has ensured repeatably accurate insertion of metal bushings into plastic parts. As a result, errors caused by manual handling were virtually eliminated, resulting in fewer complaints and increased First Pass Yield (FPY).

2. Increased production efficiency and shortened cycles - Integration of the equipment directly into the injection moulding press enabled smooth and fast assembly operations. Production cycle times were significantly reduced and production line throughput was increased, enabling better meeting of customer deadlines and increased overall productivity.

3. Repeatability and process reliability - Automated equipment guarantees a high level of repeatability with every production cycle. Process stability reduces the risk of poor quality parts and contributes to predictability of production output.

4. Reduced operating costs - Minimising the need for manual labour and reducing error rates have directly contributed to savings in labour, repair and waste costs. In addition, more efficient use of materials and energy reduces the environmental burden.

5. Improved quality of final products - Stable and controlled assembly process leads to higher quality plastic parts with integrated bushings. This results in fewer complaints, higher customer satisfaction and a better company reputation in the market.

6. Flexibility and the possibility of further development - The proposed solution allows for easy modification and adaptation for other types of parts or changes in the process, which increases the flexibility of production and prepares the company for future market requirements.

7. Monitoring and evaluation of KPIs - Thanks to the implementation of key performance indicators (KPIs), it is possible to continuously monitor the quality, efficiency and stability of the production process. This enables quick identification of potential problems and their timely resolution.

Conclusion

The project for AAH Plastics confirmed MECASYS' ability to develop and implement complex automation solutions tailored to the client's specific production needs. Thanks to precise design, manufacturing and seamless integration, it was able to optimize a key assembly process and provide the client with a competitive advantage. MECASYS is ready to transfer this experience to further projects aimed at automation and increasing production efficiency

Your needs, Our expertise

If you are looking for a partner that can turn your technology challenges into innovative, reliable and efficient solutions, turn to MECASYS. We offer development, manufacturing and integration of specialized fixtures and automation equipment that will increase the reliability, quality and productivity of your manufacturing or testing processes.

With MECASYS, you get a partner who understands the specifics of your production in detail and can turn them into successful projects - flexibly, professionally and in accordance with the highest standards. We design and deliver tailor-made solutions that support your growth and competitiveness.

Contact us and together we will turn your challenges into concrete results.

No part of this publication may be reproduced in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, stored in a retrieval system, except with the written permission of the rights holder. The request for permission must be addressed to MECASYS s.r.o., Oravská Polhora 1117, 029 47 Oravská Polhora, Slovakia.

All rights reserved, including the right to reproduce in whole or in part or in any form. Some elements contained in this publication may be used under license from third parties and may be subject to other restrictions on use.

References