Retrofitting Industrie 4.0 for digital control systems
Ypsomed Group, a medical technology company specializing in the development and manufacture of injection and infusion systems for the self-injection of liquid medicines, selected Harting to be a collaborative partner in a development project to retrofit legacy protocol plastic injection-molding machines with an integrated Industrie 4.0 digital control system that is also linked with its factory-wide MES/ERP system. This approach offers minimal physical integration with an existing production line for a low level of investment with potential long-term benefits including improved productivity, cost savings and extended machine lifetimes.
An important element of Industrie 4.0 is the ability to apply digitization to the production environment by adding more intelligence to existing processes. Taking a digital retrofit approach makes it possible to ‘smarten’ up existing processes for minimal cost over a short period of time, resulting in a fast return on investment and immediate productivity gains. Digital retrofit provides four different ways to improve production processes, increase cost savings and extend the lifetime of different types of machinery:
- Legacy machine protocol conversion
- Condition monitoring (including energy measurement)
- Asset management
- Predictive maintenance.
Central machine monitoring and process optimization offers a good way to ensure that production lines and their associated constituent parts operate effectively. Many machines in established production lines, which can be up to 30 years old, but are still performing their main functional tasks successfully. However, they do so less efficiently than their modern-day counterparts. For example, they do not have the same level of computing power, enough memory capacity to record and store relevant data, or the ability to communicate with their modern equivalents. In many cases, these machines also use data formats and communications protocols from the 1980s and 1990s, which are no longer used by today’s controllers.
Legacy machine protocols
One example of a production environment that accommodates mixed protocol legacy machines is a plastics injection molding machine (PIMM) line. Such machines, when well maintained, can attain as much as a 30-year operational life. However, some of the older software protocol operating languages cannot be directly connected to a modern factory manufacturing execution system (MES) without expensive annual custom software licensing charges. In many factories these machines still require individual programming by an operator, which can be very time-consuming in larger installations – potentially requiring input from multiple personnel.
An interesting solution to these challenges comes in the form of modular industrial computing architecture (MICA), which is a rugged edge computing device in the form of a digitally retrofittable IP67 package with Linux-based open-source software. This modular software and hardware architectural design platform permits the user to choose the programming language and development environment they are most familiar with.
This approach also offers the potential to provide Industrial Internet of Things (IIoT) web enablement and access to cloud services for Big Data analysis or virtualization, via an optional downloadable messaging queuing telemetry transport (MQTT) container. All operational software is housed in separate sandbox containers, ensuring the MICA EUROMAP 15/63 Gateway provides a secure, fully configurable interface to the plant MES/ERP, eliminating expensive custom MES access software licensing charges that may have previously applied.
Ypsomed saw the immediate potential benefits of applying this Industrie 4.0 digital retrofit approach in its manufacturing operation. Due to the high proportion of individual plastic components in its products, the company possesses a large number of plastic injection-molding machines in its production plants.
In order to improve existing levels of plant productivity, Ypsomed chose to implement Industrie 4.0 process improvements through digitization at an early stage. They started a development project to connect legacy protocol machines to its factory-wide MES/ERP system through a digital retrofit approach.
In 2017, one of the first tasks was to make data from a legacy injection-molding machine available for analysis. The machine was installed and programmed with MICA within two days as the protocol translator. Selected production data could then be collected and written to a database for offline analysis.
The next goal was to connect several different types of machines to the IT system at Ypsomed’s internal testing and validation center and present critical operational data remotely at a centralized factory control station. The machines are connected to the MES system via the MICA, which handles the protocol translation between the MES system 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 intervention by a machine operator.
Machine process parameters can now be modified more quickly, reducing downtime and enabling manpower to be more effectively employed. During manufacturing, production and process data are 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 from off-site, via a smartphone or suitable tablet device.
Additional real-time condition monitoring of key operating processes can help to reduce downtime and extend lifetime, achieving manufacturing productivity improvements. This can be accomplished by digitally retrofitting additional stand-alone MICA devices to store, analyze and process data from existing or extra retrofitted sensors. As a result, tasks such as monitoring pressure, temperature and flow rates becomes easy, whilst allowing remote centralized 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.
For asset management, A MICA radio frequency identification (RFID) variant converts the MICA device into a specific RFID reader, which, when used in conjunction with passive UHF read/write transponders that are fitted to key replaceable mold tools, allows maintenance records to be written and stored onto that particular tool. This can ensure the optimum refurbishment scheduling of high-value mold tools.
Critical operating parts of a plastic injection-molding machine, which are subject to continuous wear and tear, include the plasticizing 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 the 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 input/output (I/O) interfaces for linking to the appropriate functional I/O blocks on a machine that access this specific operating data. By pre-setting critical safe operational limits, the MICA Energy can set up alarm conditions for when these limits are breached, allowing machine operators to carry out corrective maintenance as part of the important predictive maintenance process.
Suzanne Gill is editor, Control Engineering Europe. This article originally appeared on the Control Engineering Europe website. Edited by Chris Vavra, production editor, Control Engineering, CFE Media, firstname.lastname@example.org.
Keywords: Industrie 4.0, system integration
Ypsomed Group wanted an integrated Industrie 4.0 digital control system that is also linked with its factory-wide MES/ERP system.
They started a development project to connect legacy protocol machines to its factory-wide MES/ERP system through a digital retrofit approach.
This process improved condition monitoring, asset management, and predictive maintenance.
What benefits could your company get from a digital retrofit?