“The hydraulic ram” in Kürten
Kunibert Förster
Kürtener Schriften, Volume 4, 2003, pp. 91 - 119 (adapted excerpt)
The hydraulic ram - a pump without a motor
If you ask people what a "hydraulic ram" is, you will only get the right answer in very few cases. Many people just shake their heads. Even fewer people know how it works. The hydraulic ram is a device that can pump water from low-lying points to high-lying consumers without the need for external energy (e.g. electricity). It is, simply said, a pump without a motor or, more precisely, a water-driven water pump, because part of the available water itself drives the pump. Although this device is a really elegant solution for pumping water and such devices were often used in the Bergisch region in the past, knowledge of them has been increasingly lost.
However, it was probably not particularly widespread in the past either, but limited to a few "insiders" such as water installers or farmers living in remote areas who used such devices. For one thing, the rams were not particularly conspicuous. Usually installed in a remote well, they did their job without anyone having to pay much attention to them. Secondly, most people were not entirely aware of how they worked and were almost a little secretive, so they tended not to talk about it lest they be seen as stupid and ignorant.
[Who already wants to learn more technical details, you can find out more at the very end]
The “rams” from Kürten
When searching for former rams, one almost inevitably comes across the village of Oberkollenbach.
You usually hear the news that there is a little house in the Siefen below the village which is said to have once housed a ram. On closer inspection, however, it quickly becomes clear that the little house mentioned within sight of the houses in Kollenbach had nothing to do with the ram. In fact, it housed an electrically operated pump, which in the past pumped water up from a well in the valley. The ram itself stood a few hundred meters south of the village in the Westerbach, a tributary of the Kollenbach.
The ram, as can be seen in the pictures, pumped the water into an elevated tank above the houses in Kollenbach. The distance was a considerable 500 meters, which is an impressive size for ram systems. The head of the ram to the elevated tank was around 50 meters. All in all, it was a challenging installation.
Yes, the ram still exists. Heinz Müller, a locksmith with a particular fondness for old technology and quirky technical works of art in Waldmühle, dug it out of the mud at its old location in the 1980s, which had flooded it after it was decommissioned. However, this only happened after he had conducted persistent negotiations with the owners of the Oberkollenbach water cooperative and finally put 75 marks on the table. Until around 2020, this impressive piece could be admired above a water basin directly on Wipperfürther Straße in front of Haus Müller (- today it stands at the town hall of the municipality of Kürten; see also: "Hydraulic ram at Kürten town hall").
Mrs. Annegret Irlenbusch says that her father Adolf Müller regularly maintained the ram. He was paid 1.50 marks a month for this task. However, he was also responsible for going down to the valley to check why the water was not flowing in the event of a fault.
In addition to annoying leaves, mud or branches, there were occasionally children who, out of sheer mischief, would disable the shut-off valve of the ram's water system with a stick. However, the Müllers' children often had to help themselves when it came to diverting the water. This was because there was a second distribution basin further down in the village, which supplied water to many farm animals in particular. The water distribution times were strictly defined and in times of scarce water there were even disputes about the allocation times.
The importance of the Widder water system for Oberkollenbach becomes clear when you consider that at the beginning of the 19th century, the village was the largest settlement in the southern part of the municipality of Kürten, known as "Unterkürten". Around 1830, Oberkollenbach already had almost 120 inhabitants, almost four times as many as Biesfeld. Unfortunately, it has not been possible to determine exactly when the ram was built. However, it is possible that it was built at the same time as the school, which was in operation here from 1810 to 1867. At times, more than 300 children from the entire surrounding area were taught there. Incidentally, the elevated tank was located very close to where the school once stood.
The ram, today in Kürten
Regardless of its history, the ram was in operation until after the Second World War. It was only in the 1960s, when the municipal water pipeline was laid to Kollenbach, that the ram became superfluous. However, some houses further down the village were still supplied by it until around 1970. After that, it was forgotten and sank into the mud of the Westerbach until Heinz Müller brought it back to light.
(see also: "Hydraulic ram at the Kürten town hall")
Hans Berghaus from Spitze reported that in the final phase of the "ram's life" after the war, he was called in by the people of Kollenbach to help, as they were no longer able to put the ram back into operation after the feed pipe had been replaced. But even he was unable to get the machine working again. He later realized the reason for this: the people from Kollenbach had replaced the old lead pipe with a plastic one. Due to its elasticity, this plastic pipe dampened the pressure surges to such an extent that the ram was unfortunately no longer able to work efficiently under its extreme conditions (very long delivery line with a fairly high delivery head).
The working principle of a hydraulic ram in simple terms:
A hydraulic ram (1) is a device that uses water to power itself. The water (4) flows through a tube (2) into a housing where it is suddenly stopped. This creates a strong pressure surge. This pressure surge pushes some of the water upwards (3) into a higher tank (6) or pipe, while the rest of the water drains away. The drains are controlled by closing and opening valves. The changing pressures (overpressure and underpressure) and changing flow directions play a decisive role here. The process is repeated again and again without the need for an external energy source.
The hydraulic ram therefore uses the energy of flowing water to naturally pump water to higher levels without the need for electricity or other energy sources.
Sources:
Kürtener Schriften, Volume 4, 2003, p. 91 - 119 (adapted excerpt)
Information on the operating principle based on:
