Mobile quality assurance for rail vehicle production

Stadler Rail AG is an internationally active rail vehicle manufacturer based in Switzerland and puts high-quality, high-precision trains on the rails for its customers. By using cutting-edge technology, the best economic solution is created in each case. Reliability, quality, adherence to deadlines and partnership are the values that guide the company. The PG software is an important building block for quality assurance in Stadler production. The solution guides the assembly workers through individual work sequences and thus ensures a consistent quality standard.

"For reasons of product liability, exact inspections and complete documentation are required for bolting processes in production. In this way, individual screw connections can be traced even years later," says Ronny Böhler, Head of Bogie Assembly and Surface Treatment at Stadler Winterthur AG.

Manufacturer neutrality trumps manufacturer-specific application
At the start of the project, it was particularly important for the company to find a practicable solution in the shortest possible time. It had to be manufacturer-neutral and work with the systems and tools of different manufacturers. One objective was to ensure that the processes met the highest safety standards and to document this quality.

The assembly team uses 13 modern test wrenches with integrated WLAN technology to manage and evaluate the measurement data, such as torques from bolting processes, when assembling new bogies. Two smaller and one larger test wrench are linked to a tablet.

The previous software from the manufacturer of the WLAN-supported torque wrenches had simply reached its limits with the prevailing complex processes: a test wrench stores up to 1000 data records, which have to be read out and evaluated on a daily basis. Based on this information, the previous software created huge tables of data, much of which was neither understood nor really needed by the users. This meant that the goal of ensuring quality and documenting processes in a comprehensible manner was not achieved. However, a new solution was quickly found on the recommendation of a project partner.

Modular introduction was a good option
When the project team at Stadler Winterthur AG became aware of CSP through the company Intool, the supplier of the WLAN-supported torque wrenches, they were immediately convinced: the PG software presented was manufacturer-neutral and therefore offered a wide range of options for feeding in any data.

The potential for other areas of the company outside of production and the opportunity to make information available electronically rather than on paper was obvious to those responsible. Another plus point was that the software could be introduced on a modular basis. The decision to work together was made in August 2015, and from then on the project was implemented step by step. Based on the existing infrastructure, the consultants from CSP were able to bring the system live within four days. "The 'keep it simple' principle is crucial for PG. The corresponding instructions for the workers based on images could be created very easily and quickly from within the company," emphasizes Ronny Böhler.

Anyone who makes travelers mobile also needs mobility in production: the PG worker guidance system is used on tablets at Stadler Winterthur AG. When manufacturing new train bogies, Stadler Wintertur AG relies on flexible space utilization in the production hall depending on space availability and requirements. In rail vehicle production, customers usually order individual variants and customized train bogies. Mobile worker guidance has proven its worth especially for projects for which there is no typical work sequence from A to Z. The simultaneous programming of the worker guidance system and the initial assembly of three new bogie types were successfully applied and implemented at the same time in the new EC 250 Giruno project.

Work steps are completed step by step with instructions via tablet
Using the tablet, the worker can identify the required work steps directly at the bogie and work through them in a targeted manner with guidance from PG. As with permanently installed workstations, the software uses photos or graphics on the tablet screen to show the employee which work step needs to be completed in which order. PG also communicates wirelessly with the respective tools that are to be used. Once a process has been completed, the employee confirms it. This means that the use of PG also reduces the occurrence of errors, although no separate training is required for employees for new variants.

Particularly pleasing for the Stadler team is the fact that the worker guidance runs almost without interruption - contrary to other typical experiences with new software. There were occasional minor challenges, which were quickly resolved together with CSP support. Overall, Ronny Böhler has high praise for the CSP team: "High flexibility and smooth processes: the consulting and implementation of this project within Stadler Winterthur AG worked flawlessly. This cooperation will be further intensified in the future."