Pipe Bull repairs complex pipe system in historic building

Within these historic walls lay everything that makes in-house sewer rehabilitation so complex: internal pipelines, hard-to-reach, three-sided concreted vertical shafts spanning multiple floors, a total of 1.2 kilometers of pipe to rehabilitate, diameters ranging from DN 50 to DN 400, and lines running in various dimensions and curves of up to 90 degrees.

Brawoliner and Brushcoating

With their carefully planned, innovative, and technically advanced concept for a minimally invasive, trenchless in-house rehabilitation, Pipe Bull was able to convince the client. Rehabilitation work began in September 2021. The experts from the Palatinate relied on a combination of Brawoliner HT for liner installation and a specialized brush-coating system for rehabilitating smaller-diameter pipes. A unique feature of the project was the use of ultra-small milling robots, requiring particularly delicate handling from the Pipe Bull team. The client also appreciated the team’s strong communication with the residents of the historic building throughout the project.

A special challenge: complex pipe routing

Following the pipe cleaning, TV inspection, and initial prep work—also carried out by Pipe Bull—it became increasingly clear: this was an extremely complex rehabilitation. The pipe layout included numerous 90-degree bends and DN 100 downpipes that also ran through several right-angle turns. On top of that were numerous, unexpected changes in diameter, with pipe cross-sections alternating between larger and smaller. The TV inspection further revealed the extent of the pipe damage. This scenario demanded maximum flexibility and technical expertise from Pipe Bull.

Historic building with a modern wastewater system
Next, the team installed the Brawoliner HT using the open-end method. Specially designed for in-house rehabilitation, this DIBt-approved liner is a seamless, highly flexible textile hose that accommodates varying pipe diameters and up to two dimension changes. To ensure the liner cured evenly and without wrinkles during air inflation, Pipe Bull used a Bluetooth-connected pressure monitoring system that triggered an alert if air pressure dropped. For the first time, they used an electrically powered Vortex Cutter to open the inflow connections. For pipes that were not suitable for the Brawoliner HT, the team used the brushcoating method—a special brushing technique for cleaning, coating, and lining the pipes with a two-component epoxy resin.

By the end of 2022, the sewer specialists from the Palatinate had successfully completed the in-house rehabilitation of Barthels Hof. The result: a historic building complex with a fully renewed wastewater system – modernized using state-of-the-art technology.