After over a decade of research and development in waterjet technology, Novajet was established as a spin-off from Chemnitz University of Technology in 2019. The company's founders had spent many years working on improving waterjet performance, developing a solution that enables even the smallest structures to be reliably cut using a waterjet. This resulted in the creation of micro-waterjet systems for precision waterjet cutting. The Chemnitz-based company also offers waterjet cutting services. However, as they began receiving an increasing number of enquiries for tasks beyond precision cutting, they started using waterjet cutting systems from other manufacturers for these services. While running these systems, the experts identified various opportunities for optimisation and energy savings. However, to make these transparent and actionable, they needed digital process and energy data. By analysing and comparing this data, they were able to identify various potential savings. They concluded that condition monitoring, preventive maintenance and energy consumption would also benefit from such a solution. However, the effort and costs involved in integration would need to be proportionate to the benefits. In their search for an easy-to-retrofit digitalisation solution for process and energy data monitoring, they found what they were looking for in in.hub. The company offers smart IoT and IIoT devices for the digitalisation of industrial machinery and processes.
Digitising expertise
The cutting nozzle is one of the most important components in waterjet cutting. The Chemnitz-based team identified this area as having the greatest potential for cost savings. Due to the waterjet and the abrasive used, depending on the application, cutting nozzles undergo natural wear and tear. They must therefore be replaced at regular intervals. An experienced machine operator can assess the condition of a cutting nozzle by the sound it makes and take action if necessary. However, as long as people are so closely involved in the manufacturing process, it remains a craft and is difficult to automate. In this context, it also makes sense to digitise expert knowledge. One reason for this is the shortage of skilled workers, and another is that the systems are expected to operate reliably around the clock, including during 'ghost shifts'. Markus Dittrich, owner of Novajet GmbH, reports: 'Through our research, we had already gathered extensive expertise on how to assess the condition of our systems using various process parameters. We were then looking for someone to help us turn this knowledge into solutions suitable for industrial use.' In.hub was able to provide general support in the form of a plug-and-play solution for retrofitting process data and energy monitoring technology via appropriate IIoT gateways. The company also offers various tools for specific challenges, such as the HUB-VM102. This device continuously monitors vibrations in machines and components in industrial settings.
Gradual retrofitting of digitalisation using a modular approach
Christian Groß, Managing Director of in.hub GmbH, explains: 'The typical trigger for retrofitting a plant with digitalisation is energy management. At Novajet, however, things were slightly different. Here, the initial requirement was for a vibration monitoring solution. In both cases, however, the right tools are needed for fundamental digitalisation retrofitting, which enables various solutions to be used.” To capture, process and analyse machine and process data, a suitable gateway is first required for this use case. Novajet uses the HUB-GM200 for this purpose. Connected to the machine’s Siemens S7 controller via the integrated S7 PLC client, it monitors critical components together with additional sensors or expansion modules. The make and year of manufacture of the machine, or the type of controller, are generally irrelevant for integration purposes, as the gateways can easily be connected to almost any system via standard interfaces using plug-and-play. Groß adds: 'We’re all familiar with the USB interface on a PC, which allows all sorts of devices to be easily connected. Our aim was to develop a similarly simple solution for the industrial sector.”
Integration works so seamlessly thanks to the in.hub operating system, which was developed specifically for IoT environments. It offers pre-configured functions for independently implementing IIoT projects. The operating system and all pre-configured functions are pre-installed on the in.hub IoT gateway and are also available to download as an app. Set-up requires no coding or programming whatsoever. Depending on the customer’s requirements, all process data can then be stored in a local database or in the cloud. The waterjet cutting experts use MaDoW (Monitor and Downtime Watch) to visualise the process data. Here, the collected machine data is visualised in real time. System downtime, anomalies and efficiency figures can be clearly viewed. Dittrich reports: “What impresses me most is how incredibly easy the digitalisation integration was. It only took a few minutes to install the gateway, software and vibration measurement module, and set up the visualisation.”
Retrofit of structure-borne noise measurement for cutting nozzle
The waterjet experts had more work to do when analysing the structure-borne noise measurement data. This data is complex and requires specialist knowledge. Dittrich's many years of research were an asset here. Combined with real-world operational data, it allowed Novajet to develop parameters for determining wear and tear on the cutting nozzles. This allows alarms to be triggered when the cutting nozzles are no longer functioning properly, enabling production to be halted immediately to avoid scrap. On the other hand, it enables preventive maintenance. Dittrich explains: 'Without analysis, it is difficult to say how long a cutting nozzle will last. Their lifespan varies significantly, ranging from around 15 to 50 hours. Now, the nozzles no longer need to be replaced preventatively, but only once they are actually worn out. This brings immense savings.'
However, as analysing structure-borne sound data is complex and requires specialist expertise, in.hub is currently developing an app for standard applications involving pumps and fans to simplify this process. In the meantime, the waterjet cutting experts are offering their retrofitting expertise to other operators of waterjet cutting systems. 'If you’re interested, we can handle the retrofitting of a system, including the relevant tools, data analysis and associated visualisation,' reports Dittrich.
Energy management and more
Novajet also found the modular approach, which allows various digitalisation solutions to be introduced step by step, to be extremely useful. Once the structure-borne noise measurement had been implemented, the question arose as to how energy efficiency could be improved. To this end, they installed the HUB-EN200, an add-on module for energy monitoring. Only by comparing process and energy data can one decide whether high consumption levels are technically justified or indicate anomalies. The air management system (AMS from SMC), which was already in use for the compressed air systems, was also integrated into the analysis via the EN200. As SMC is an in.hub partner, this integration works via simple plug-and-play. This information makes it possible to see precisely when specific energy consumption occurs and to cross-reference it with the control data, thereby enabling discrepancies to be detected at an early stage. Compressors are often situated out of the way due to the noise they generate, making them easily overlooked. However, leaks can quickly lead to significant compressed air losses. As the production of compressed air is energy-intensive, this leads to high energy losses. These can now be detected directly using the digitalised solution. Christian Groß sums up: "Many users are unaware of the condition and productivity of their plant because they cannot record the relevant OEE metrics. However, they shy away from digitalisation because they are put off by the effort involved. With our solutions, however, you can get started with little effort.” Many plant operators start with digital solutions for energy management, then develop further ideas about what else they could monitor once digitalisation has been implemented in one area. However, it is also possible to take a different approach, as Novajet has done. No matter which starting point you choose, in.hub’s modular solutions enable you to create a digitalised system in a short space of time and with minimal effort as part of a retrofit.
