Special cleaning for petrified spring water
Systems and technologies involved
- MicroGator GT operated with the KW 306 cable winch, an ultra high pressure water jet nozzle and the CutterCam
Job
"Mineral deposits from springs" is a frequent clue in crossword puzzles; however, they cause major problems in rainwater sewers. This was experienced by the municipality of Röfingen in the Swabian district of Günzburg where rock-hard sediments obstructed the flow in concrete pipes with pipe dimensions of DN 300 to DN 500 for more than 440 metres. The rock had accumulated in layers in the invert due to the flow of natural spring water and had led to a 50 per cent blockage of the pipes. The solution here was ultra high pressure water jet technology to effectively and efficiently counteract the extensive massive disruption.
Solution
"I prefer to work in the direction of flow, because then the material can run off. First I go through once for the rough cleaning, then the loosened material is removed. Then I go through again for the fine work. We do the acceptance inspection immediately afterwards. This is done with the same machine," says Patrick Eisenring, explaining his tried-and-tested procedure.
The removal performance depends on the choice of nozzle type in combination with the water volume, the pressure and the travelling speed of the robot. To remove the petrified spring water in the rainwater sewer in Röfingen, among other things, he used a 4-jet rotary nozzle at a water pressure of 1500 to 1800 at around 22 litres per minute. "This creates an enormous recoil force. The MicroGator GT Lite has to counteract this. And it does! Even when we work with 26 litres and 2500 bar," reports the 35-year-old. He knows how to skilfully exploit this recoil force for his cleaning technology: "The fact that I can set the parameters so precisely via the IBAK control system allows me to work with great precision. I don't keep the nozzle focussed on one spot, but always drop back a little and then pass by again." In this way, he removes layer after layer in a steady motion and continues to work his way forwards. "In Röfingen, for example, I was able to clean well at 12 per cent driving speed and also had enough propulsion so that we cleaned up to 90 metres per day," he continues.
But it is not only the power of the GT Lite that is needed to optimise the cleaning performance of the water pressure underground. Precise control via the IBAK system is also necessary for a perfect cleaning result. The angle of incidence of the respective nozzle can be adjusted so that only the material to be removed is worked on and not the pipe wall. "I can always align the nozzle perfectly, even for the fine work, so that the old pipe substance is preserved. We have even utilised the 4th axis to clean into a connection pipe that was at 2 o'clock position. This is possible because I can precisely approach any point in the pipe," emphasises Patrick Eisenring.
He observes his work in the sewer on the monitors in the vehicle's control room. The CutterCam camera integrated into the GT Lite gives him an unrestricted view of his work area. Patrick Eisenring can closely monitor the progress of the removal and adjust his approach in a controlled manner if necessary. "We always shoot the material away from us," he emphasises, pointing out that with ultra high pressure water jet technology, the tool itself does not come into contact with the material to be removed.
Result
Patrick Eisenring and his father are visibly satisfied with the successful conversion and expansion of the vehicle, which has opened up a new range of services for them. The job in Röfingen shows that ultra high pressure water jetting technology is an efficient and precise cleaning method for sewer maintenance. The job was completed quickly and without damaging the pipe substance.
Challenge
Ultra high pressure water jetting technology currently only accounts for a few per cent of all orders, which is due to the lack of personnel: "Like so many other firms, we are also looking for motivated people to join our team. Our job gives you a good feeling at the end of the day because the success of the work is immediately recognisable. I can only encourage people to take the step of joining our industry, which is so varied. We have four women working for us, two of whom actively work in the field. Jennii is a trained hairdresser and initially worked with me on an inspection vehicle for a year and a half. She qualified as a sewer inspector four years ago and completed the advanced course for manhole inspection last year. She is an asset to us and a great example of how our industry doesn't have to be a male domain," says Patrick Eisenring. He would like to use the ultra high pressure water jet technology more often, as the demand for this specialised cleaning method is huge, especially from an economic point of view.
Company introduction
The name Kanal-Eisenring unites a 14-strong team that serves a customer base throughout southern Germany with 14 vehicles, state-of-the-art technology, specialist expertise and innovative ideas. The family business that was founded in 1961 has developed over three generations from one-man operation into a full-service provider with a comprehensive range of services from pipe and sewer cleaning to sewer TV inspection and leak testing of sewers. "As different as our customers' problems are, our services have to be just as varied and innovative," explains Martin Eisenring, who already took over his father's business at the age of 20. The creative inventor is proud that he has been successfully running the company which is based in Sontheim on the river Brenz together with his eldest son since 2014. Patrick Eisenring shares his father's passion for developing customised technical products and integrating them into vehicles. This is also how the two of them breathed new life into an old, supposedly disused IBAK TV vehicle. In addition to inspection, the system can now even be used for a completely new task: ultra high pressure water jet cleaning.
