Roller weir
![](https://upload.wikimedia.org/wikipedia/commons/thumb/1/16/Roller_dam_-_Walzenwehr.jpg/220px-Roller_dam_-_Walzenwehr.jpg)
A roller weir is a movable weir . The technology of the roller weir was developed by the German engineer Max Carstanjen (1856–1934) for the weir system in Schweinfurt . It was patented and built by Maschinenfabrik Augsburg-Nürnberg (MAN) and first put into operation in 1902 at the so-called bottom outlet .
Depending on the width of the water, the weir consists of two or more weir piers, in the flanks of which the cylindrical hollow rollers are mounted so that they can be adjusted in height and rotated by means of a chain drive . The guides are usually inclined to reduce the operating forces. Outside the guide, the rollers are usually eccentric, so that by lowering or lifting while rotating at the same time, the backwater of the headwater and the water flow above and below the weir gate can be regulated.
In contrast to the needle weirs that are rarely used , roller weirs are much easier to operate and much more powerful. They can withstand a higher water pressure and thus generate a higher level of stagnation - thus also a greater water depth - which, if necessary, enables greater spacing between the barrages. During the expansion of the waterways since the 1920s, the barrages were therefore mainly equipped with roller weirs. Roller locks are the most commonly used on waterways today, but are increasingly being replaced by hose weirs.
The Lock and Dam No. 15 in Rock Island in the US state of Illinois .
A three-part Roller Dam:
The dam Griesheim in FrankfurtWeir pillar with the roller suspension at the Offenbach barrage
The world's first roller weir at the bottom outlet in Schweinfurt
The world's largest roller weir in Rock Island (Illinois)
Roller weir, Salztorstrasse in Kassel
Barrage roller weir at the Kostheim barrage , Hesse
Web links
- Presentation of the roller weir: segment gate and roller weir , Zentralblatt der Bauverwaltung, November 1907
- Website of the Wasser- und Schifffahrtsamt Schweinfurt