By Howard Forryan, Product Market Specialist, Harting

An important element of Industry 4.0 is the ability to apply digitisation to the production environment by adding more intelligence into existing processes. Initially, manufacturers have been wary of Industry 4.0, on the assumption that effective implementation would require major and expensive changes to production lines. However, through digital retrofit, it is possible to “smarten” up existing processes at minimal cost over a short period of time, resulting in a fast return on investment and immediate productivity gains.

Digital Retrofit

Digital retrofit provides four different ways to improve production processes, increase cost savings and extend the lifetime of machinery:

• Legacy machine protocol conversion;
• Condition monitoring (including energy measurement);
• Asset management;
• Predictive maintenance.

Legacy machine protocol conversion

Central machine monitoring and process optimisation offer the best way to ensure production lines and their parts operate effectively and economically. Many machines in well-established production lines, some of which between 15- and 30-years old, can still successfully perform their main functional tasks. However, they do so less efficiently than their modern-day counterparts; they lack the same level of computing power, memory capacity (to record and store relevant data) and communication functionality. In many cases these machines also use data formats and communications protocols from the ‘80s and ‘90s, which are no longer used by today’s PLCs and industrial PCs.

A prime example of a production environment that accommodates mixed protocol legacy machines is a plastics injection moulding machine (PIMM) line. Such machines, when well maintained, can last as long as 30 years. However, some of the older software protocol operating languages (e.g. EUROMAP 15) can’t be directly connected to a modern factory MES (Manufacturing Execution System) without expensive annual custom software licensing charges. In many factories these machines still require individual programming by an operator, which is time-consuming for larger installations, and may require more personnel.

Harting’s MICA Solution

An innovative solution to these challenges is offered by Harting’s MICA (Modular Industrial Computing Architecture): an edge computing device in the form of a digitally retrofittable IP67 package with Linux-based open-source software. This modular software and hardware platform permits the user to choose the programming language and development environment they are most familiar with. MICA is rugged, compact and maintenance-free, and hence suitable for use in the harshest industrial environments.

For the plastic moulding manufacturing environment, there are MICA EUROMAP 15 and MICA EUROMAP 63 gateway variants, which convert the legacy EUROMAP 15/63 TCP/IP machine operating communications protocol into OPC UA, for example via an intermediate JSON software format. This approach also offers the potential to provide IIoT web enablement and access to Cloud services for Big Data analysis or virtualisation, via an optional downloadable MQTT container. All operational software is housed in separate sandbox containers, ensuring that the MICA EUROMAP 15/63 gateway provides a secure, fully-configurable interface to the plant MES/ERP, eliminating expensive custom MES access software licencing charges that may have previously applied.

Condition monitoring

Additional real-time condition monitoring of key operating processes can help reduce downtime and extend lifetime, thus achieving manufacturing productivity improvements. This can be accomplished by digitally retrofitting additional standalone MICA devices to store, analyse and process data from existing or extra retrofitted sensors. As a result, tasks such as monitoring pressure, temperature and flow rates become easy, whilst allowing remote centralised process control adjustment via the MES network. Communication with the machine-fitted sensors is achieved via a simple Ethernet switch and interlinked active I/O blocks.

Asset management

For asset management, A MICA RFID variant converts the device into a specific RFID reader, which allows maintenance records to be written and stored onto that particular platform when used with passive UHF read/write transponders that are fitted to key replaceable mould tools. This can ensure the optimum refurbishment scheduling of high-value mould tools.

Predictive maintenance

Critical operating parts of a plastic injection moulding machine, which are subject to continuous wear and tear, include a plasticising screw pump and associated check valves. As wear increases this can result in a significant number of rejected parts and expensive financial losses. This situation can be resolved by monitoring changes in the operating power curve characteristics of the screw pump and the pressure loading at the check valves.

Integration of a MICA energy variant provides RS485 Modbus TCP/IP-compatible I/O interfaces for linking to the appropriate functional I/O blocks on a machine that accesses this specific operating data. By pre-setting critical safe operational limits, the MICA Energy can set up alarm conditions for when limits are breached, allowing machine operators to carry out corrective maintenance as part of the important predictive maintenance process.

Benefits for Ypsomed

As an established Harting customer, Ypsomed saw the immediate potential benefits of applying this Industry 4.0 digital retrofit approach in its manufacturing operation at its headquarters in Burgdorf, Switzerland. Ypsomed Group is an international medical technology company specialising in the development and manufacture of injection and infusion systems for liquid medicine self-injection. It produces several hundred million products a year and meets the highest medical technology quality standards. Due to the high proportion of individual plastic components in its products, the company possesses many plastic injection moulding machines.

To improve its plant productivity levels, Ypsomed chose to implement at an early stage Industry 4.0 process improvements through digitisation. Ypsomed turned to Harting to connect legacy protocol machines to its MES/ERP system with the digital retrofit approach.

In 2017, one of the first tasks was to make data from a legacy injection moulding machine available for analysis. The machine only offered the old EUROMAP 15 protocol and, consequently, Harting’s Edge Computer MICA was installed and programmed within two days as protocol translator. Selected production data could then be collected and written to a database for offline analysis.

The next step was to connect several different machine types to the IT system at Ypsomed’s internal testing and validation centre, and present critical operational data remotely at a centralised factory control station. The machines are connected to the MES system via the MICA, which handles protocol translation between MES systems and the shop floor. Here, the configuration data record belonging to a production order from the ERP system is retrieved from a database and automatically transferred directly to the machine via the MICA, without requiring operator intervention. Machine process parameters can now be modified more quickly, reducing downtime and enabling manpower to be much more effectively employed.

During manufacturing, production and process data is temporarily stored on the MICA and fed back to a database or ERP system for ongoing quality improvement or record storage purposes. Machine operators can even monitor and affect the process of the production line remotely, via a smartphone or suitable device.

The new production plant in Schwerin, Germany, is planned to start operations in summer 2019. Automated control of production orders will be implemented by 2020.