While the manufacture of products is becoming more and more complex these days due to increased requirements, for example in terms of digital networking and remote maintenance options, the desire for more flexible quantities is also increasing. This requires dynamic planning, particularly in order to avoid downtimes in production. "This can lead to an increase in errors by personnel, especially in assembly-heavy production processes, as the process overview is quickly lost due to the complexity," reports Stephan Böing, Head of Process Engineering Change Management & Product Care at WILO SE. "Using the wrong component or dealing with extensive parts lists in the form of paper orders are just two examples of possible causes of errors." In order to relieve the burden on employees and at the same time raise production to a new level of efficiency, Wilo SE is therefore relying on particularly modern production with a mix of HRC (human-robot collaboration), AGVs (automated guided vehicles) that independently search for the next free assembly station, and intelligent production systems equipped with digital worker guidance when restructuring its production site in Wilo-Park.

In order for this comprehensive digitalization of production to succeed, the pump manufacturer sought out a strategic partner in Soma GmbH, which has extensive experience in the field of industry- and product-specific testing and automation systems. "As part of the order, we developed and implemented five end-of-line and production test systems as well as around thirty different manual workstations that are connected to the higher-level flexAssistant plant management system," reports Wolfgang Thater, Head of Sales at Soma. "The flexAssistant also works as a worker guidance system and coordinates the status of the various assembly stations and AGVs with each other, enabling open interlinking of the work steps and a much smoother flow of goods."

Higher-level worker guidance software minimizes human error

The flexAssistant basically replaces paper-based instructions and documentation with digital assembly guidance: the operator receives all relevant information about the current component and the necessary work steps to be carried out at this assembly station via a monitor. "In the past, our colleagues in production had to use parts lists to identify the relevant parts. This required the specialist knowledge of experienced colleagues, especially for new products or more complex work steps," explains Böing. "Of course, this also resulted in longer training times." The new, digital worker guidance system, on the other hand, provides the fitter with virtually illustrated assembly instructions so that, for example, choosing the wrong screwdriver or assembling a component in the wrong place is virtually impossible.

The flexAssistant acts as an intelligent hub for the entire line, as all the data from the various production stages in the plant flows together there - this also enables seamless documentation of all assembly steps in real time. "A worker no longer has to accompany a product through all the assembly stations, but can work at different stations regardless of the sequence," says Thater. "The more procedures the employee has to master, the more useful and practical the support provided by flexAssistant is." The first voices from production show that this works: employees who have already been able to work with it have praised the way it safeguards their own work.

In addition to the digital instructions, the flexAssistant controls and monitors all screwdriving, removal, functional test and product parameterization processes in the line. The flexAssistant modular system offers scalable solutions from the workstation to the software and a wide range of handling devices for individual solutions. "The flexAssistant software is based on an established sequencer that can be used to parameterize individual processes," explains Thater. "As it is a standardized platform with maximum flexibility, the integration of new modules, for example, is also made easier." With this adaptable structure, processes can be carried out and adapted independently and quickly at all workstations. As the flexAssistant is "parameterized" during operation without programming knowledge, independent and rapid adaptation is possible at any time.

The flexAssistant's maximum connectivity offers the freedom to integrate new special and intelligent modules. "These expansion options and the flexible team at SOMA GmbH were the decisive factors for us in planning our factory of the future based on flexAssisstant," explains Böing. Thanks to the consistent concept for all systems, from the assembly process to the Eol (end-of-line) tester, it is easy to operate and works independently of language, so that the software can be switched to the respective national language.

Cycle losses are compensated for by an open assembly sequence

"Thanks to the constant exchange of information between the individual workstations and assembly sections, errors are compensated for as soon as they occur, as the system stops the onward transport and redirects it accordingly, for example for manual analysis in the event of faulty assembly or back to a previous station for readjustment," explains Böing. "This prevents delays in the subsequent parts and makes production much more time-efficient." What's more, the individual assembly steps take different amounts of time, which can lead to cycle losses without software. Thanks to the free linking of the assembly stations and the flexible routing of the AGVs, these are compensated for by overtaking processes. The system can automatically reroute the transport units to prevent incorrect onward transportation. If, for example, a fault is registered, a message is sent to an available AGV, which leaves the pre-calculated route and automatically picks up the faulty product, for example to go to analysis instead of packaging.

In order to get employees used to the new, digital way of working without burdening production, a training line was also equipped with the new flexAssistant, on which new work steps can be tested before they are transferred to the actual assembly lines. In addition, corresponding sequences for the assembly lines were created in collaboration with WILO and stored as a program instead of laboriously writing new work instructions. This will make it much easier to implement and link new work steps or adjustments in the future. The two companies also want to work together beyond the current project in the future. In the area of big data, for example, possibilities for further processing and utilizing the data are being examined. The integration of electronic checklists and projecting systems into the production line is also being considered. "For us, Soma GmbH is the right partner for the future thanks to its experience and regional proximity. We look forward to continuing to pursue smart paths together," concludes Böing.

SOMA GmbH, www.soma.de