Application Technology

Porsche AG, together with its long-term supplier tesa SE, has developed an innovative robot assisted manufacturing process at its headquarters in Zuffenhausen, Germany, for hole coverings in car bodies.

Across the globe more than 10 billion holes in car bodies each year, necessary for the e-coat painting process, must be closed for corrosion protection. This is typically done manually by pushing bulky plastic plugs into the holes, which is an extremely time-consuming and physically demanding task for workers. Per shift, workers push more than 3,500 plugs to seal the holes, often working in an overhead position. By doing so, they need to apply a thumb pressure per plug equalling 7kg – an enormous ergonomic strain. The alternative is sealing patches from adhesive manufacturer tesa – applied by a robot quickly and reliably.

The fully electric Porsche Taycan is the first vehicle in the world to use a new automation technology for efficient hole covering, thus optimising the entire production process. By summer 2021, Porsche AG will implement this new concept at its Leipzig plant. “The cooperation with Porsche is an excellent example of how tesa, as a long-term partner of the automotive industry, drives innovations and offers future oriented solutions to bring value to our customers,” explains Angela Cackovich, board member direct industries at tesa SE.

Compared to conventional plastic plugs, tesa sealing patches feature a variety of advantages. While plugs always must match perfectly, it is possible to cover holes of different dimensions with one patch size. This reduces the overall complexity and saves time.

tesa patches can also provide additional benefits. The base product, tesa PunctureGuard, ensures corrosion protection via perfect sealing – combined with high mechanical strength and good noise dampening properties. Additionally, these durable adhesive patches, which are only 1mm thin yet extremely tough and last a car’s lifetime, are significantly lighter than the approximately 6mm plastic plugs. This is of great relevance for e-cars, as every extra gram means a loss of range.

tesa’s special product tesa FireGuard, developed for the so called Battery Foot Print, withstands flames of up to 500°C for six minutes, protecting the passenger compartment to allow driver and passengers to get out of the vehicle in case a defect battery catches fire.

“Our automatic application unit, tesa EfficienSeal, was developed utilising tesa expertise and guarantees customers that holes are effectively sealed,” explains David Caro, corporate vice-president of the tesa business unit automotive. “Also, the positioning accuracy is significantly higher compared to the manual process. The sealing operation becomes 100% effective and can be performed in half of the time compared to the traditional process.”

Using this innovative automation technology, tesa automotive customers benefit from a high degree of flexibility. Depending on vehicle type, as well as the related number and sizes of holes in the car body, the robot can exchange end effectors quickly based on the sealing patch type and size needed.