Joint arch extension
The articulated arch support is a multi-part articulated roadway support , which in the mining underground in routes is installed, the high ground pressure are exposed.
construction
The articulated arch extension is also known as a two-part articulated arch extension, it consists of the superstructure and the substructure. The superstructure is formed by two steel arches that are connected to one another via a shell joint. There is also a joint socket at the lower ends of the two extension segments. These joint shells are rigidly connected to the extension segment. If the joints cannot be placed directly on the standing mountain , a full fit must be achieved by backfilling . The substructure is created in different ways. One design of the substructure is the use of two sharpened and burned-in block or lower stamps . A pinch cap is attached to the top of the punch head on each punch . A round piece of wood is placed on this as a so-called runner. The joint shell of the extension segment is placed on the curve of the runner. Another type of substructure is the use of wooden or recovery boxes . There is also a runner on the boxes as a bearing for the extension segments. Instead of the wooden stamps or wooden boxes, steel stamps are also used, which are connected to the extension segment via a steel joint. Instead of the lower hinges, pillars can also form the substructure. The miner calls an articulated arch extension with stamps as a substructure, a five- hinge extension , and an articulated arch extension with boxes as a substructure he calls a three- hinge extension .
Mode of action and use
Due to the joints between the segments, the cross-sectional shape of the joint arch expansion is variable. The expansion is particularly suitable for stretches with mountain pressures in the upper dip area. Articulated arch extension with wooden or recovery boxes as a substructure is mainly used in flat storage. In order for the expansion to work properly, the miner must assemble and set the expansion according to the installation instructions.
Individual evidence
- ^ A b Walter Bischoff , Heinz Bramann, Westfälische Berggewerkschaftskasse Bochum: The small mining dictionary. 7th edition, Verlag Glückauf GmbH, Essen 1988, ISBN 3-7739-0501-7
- ^ A b Carl Hellmut Fritzsche: Textbook of mining science. Second volume, 10th edition, Springer Verlag, Berlin / Göttingen / Heidelberg 1962