Industry 4.0 in action
Bosch Rexroth is recognised for its dual Industry 4.0 strategy, whereby it develops Industry 4.0 technologies in its own factories before introducing these to industry. An example of this is a production facility at Homburg which demonstrates what can be achieved with Industry 4.0.
Industry 4.0 is the latest manufacturing trend, but there are precious few real world examples which offer tangible and quantifiable benefits. The Bosch Rexroth factory at Homburg provides a great example of an actual Industry 4.0 production line in action.
There has been a lot of talk about the concept of Industry 4.0 but few companies appear to have really embraced the so-called fourth industrial revolution.
For some time now Bosch Rexroth has been employing a dual strategy, which sees the company develop Industry 4.0 technologies in its own factories, before rolling out proven solutions to industry.
The production facility at Homburg in the Saarland region of Germany is a case in point. The plant manufactures hydraulic valves for mobile machinery, such as tractors and forklift trucks. The company made the decision to introduce Industry 4.0 on one specific manual production line which was struggling to keep up with Bosch Rexroth’s commitment to quality, and the demands of its customer base.
“We identified three areas where we needed to deliver significant improvement, namely quality of the product, cost and delivery times,” explained Dr Matthias Möller, Director of the Technology and Process Planning Department at Bosch Rexroth’s Homburg plant.
The core of the problem was that the line was manufacturing six main valve product types with 250 variants and 2,000 individual parts. Furthermore, the line had to be highly flexible, working with small batch sizes requiring assembly experts for each product family.
“The key factor is that we wanted to develop a zero failure strategy because the market for hydraulic valves is very demanding in terms of quality,” says Möller.
With a complex manual production line, the Homburg plant was struggling to meet customer demands. Bosch Rexroth therefore set out to develop a zero failure strategy with a quality first approach. The creation of an autonomous connected workspace has transformed production, delivering significant improvements in quality, productivity and efficiency, whilst keeping employees at the heart of the process.
For Bosch Rexroth, the solution was to use the Industry 4.0 philosophies of connectivity, open standards and the virtual representation of information while keeping people, namely the assembly line employees, at the heart of the process. Specifically, the valve production line at Homburg was re-engineered into autonomous workstations with RFID chips controlling the product as it flows through the line and sensors collecting and collating data which is used to frame the decision-making process.
“To achieve such dramatic changes, we set about adapting the production unit, setting up nine autonomous intelligent workstations that can quickly switch between products as required,” says Dr Möller.
Work steps for each different product type are displayed to employees on screens at every workstation, using a Bosch Rexroth technology called ActiveAssist which facilitates quick and easy learning, all the time aiding flexibility. The system guides assembly steps using a pick-to-light system which eliminates errors and checks all assemblies, via a 3D camera. Meanwhile, kanbans and part supermarkets provide the parts to the operator relevant to the specific valve being manufactured.
“The logistical task was driven by the quality requirement, namely that only essential components were allowed to be at the workstation, to avoid the incorrect assembly of components,” Dr Möller explains. “Now we have the pick-to-light technology combined with RFID identification of each single product, we can leave all components at the line all the time. This is because we are able to ensure that only the necessary components for the new run are picked by the worker.”
Crucially, each workstation recognises employees via a Bluetooth tag and then adjusts the work area automatically to individual requirements including language, font size and individual skills and experience of the operator, while a quality assurance app tracks the full process for any faults or deviation.
“Every step of the process is recorded and relayed to production operatives in real time using RFID chips to monitor the position of individual components. Using ActiveAssist, each worker receives exact instructions tailored to their skill level and preferred language,” says Dr Möller.
The brain of the Homburg line is another Bosch Rexroth innovation, namely ActiveCockpit, an interactive manufacturing system which collects, filters and visualises manufacturing data continuously, giving employees and management real data to facilitate fast decision-making.
ActiveCockpit provides a digital connection between operator, product, workstation and process, collecting, filtering and visualising data on a whiteboard which is, crucially, located close to production process. The whiteboard displays key production data live, in both stationary and mobile forms, seamlessly integrating the virtual world of order planning and production control, with connectivity to the manufacturing execution system (MES) and Enterprise Resource Planning (ERP).
Using ActiveCockpit, key data coming off the Homburg valve production line is real-time with status, annotation, notes and ‘to do lists’ which are accessible to all staff members. The system also automatically creates reports with all relevant information and appendices dealing with the discussed topics.
The results of implementing Industry 4.0 speak for themselves. Logistical and set-up time was reduced from 450 seconds in 2014 to zero one year later. Inventory days were reduced from three days in the same period down to 1.5 days. Cycle times reduced from 474 seconds in 2014 down to 438 seconds in 2015. Overall the Homburg valve production line has undergone a 10% production improvement and achieved a saving of half a million euros annually.
“Each stage of the process is fully integrated from the customer placing the order with the OEM through to suppliers, component machining, assembly, test and shipment, with capacity fully scalable and adaptable to demand, based on short-term order fluctuations,” says Dr Möller. “We’ve already seen a 30 per cent stock reduction, eliminated set-up time, and achieved a 10 per cent output increase, resulting in an annual saving of €500,000.”
Dr Möller adds: “Our experiences in Homburg demonstrate that productivity savings from Industry 4.0 can be achievable now and are fully scalable. Focusing on just one production cell, we’ve achieved major production savings and additional revenue from a 10 per cent increase in output.
“It was realised with connectivity,” he states. “The previous production set-up required the removal of all unnecessary components during changeover from one product to another and the restocking of lines between production runs took up to 450 seconds per changeover.”
Going forward Dr Möller believes that Industry 4.0 techniques will be implemented across other lines in the plant. “We are implementing Industry 4.0 solutions to the next steps in our value stream. Having started with valve assembly, we are now looking at the machining area and will follow up with the valve test area. We are certain there are huge potential benefits from connecting worker, machine and material for industrial production in this way.”
For further information please visit www.boschrexroth.co.uk/industry4-0