Rope basket
A rope basket , also known as a basket , driving basket or drum , is a device on the hoisting machine on which the hoisting rope is wound. With the cable basket, the circular movement of the hoisting machine is converted into a straight one.
Layout and function
Each cable cage consists of a center piece, also known as a star, that sits on the cable cage shaft. On the side of the middle piece are the wreaths that are attached to the so-called arms of the middle piece. The casing is located between the wreaths. Probably the oldest form of the rope basket is the cylindrical rope basket. These baskets were constructed so wide that all rope laps could wind up next to each other on the drum. Due to the large enough width, the hoisting ropes were prevented from winding on top of each other. However, these cable baskets had the disadvantage that the changing weight of the winding or unwinding hoisting rope is noticeable in a disturbing way. The conical rope baskets provided a remedy here. Conical rope cages are shaped in such a way that the hauling rope winds up onto the rope cage at an angle of inclination of 2: 1. The conical cable baskets almost compensate for the changing weight of the hoisting cable. Grooves can be milled into the casing of both the conical and the cylindrical cable cage. Rope cages that have a slightly conical body and are provided with milled grooves are called spiral rope cages. The grooves are attached in such a way that they have the shape of a screw thread. So that you can move two conveying vessels at the same time, there are both cylindrical and conical double drums. The conical double drums are joined either at the wide or at the narrow end faces. This gives you two different types of conical rope cages.
Wooden rope baskets
The rope baskets of the Göpel powered by muscle or water power were made of wood. The cable cage shaft was made from particularly strong wood. Iron pegs were attached to the ends of the shaft, with which the shaft ran in cast iron bearings. The cable drums were attached to the cable cage shaft by means of cross timbers. To ensure that the cable cage was tight enough, it was connected to the shaft with bolts. The wooden wreaths were attached to the cross timbers. In the case of drums with a particularly large diameter, it was necessary that the wooden wreaths were reinforced with struts. These struts were attached between the wooden wreaths. In addition, struts were also attached between the rings and the shaft. The battens used as casing were attached with nails in such a way that no nail head protruded from the outer surface of the basket. This was necessary so that the hoisting ropes were not damaged. If hemp ropes were used, they had to be coated with tar to protect against moisture. This tar settled on the casing and had to be removed from time to time so that the hoisting rope could unroll from the rope cage without any problems. When using steel ropes, the rope cages had to have a minimum diameter of 2.64 meters in order not to exceed the elastic limit of the ropes. In the Upper Harz mountain area, rope cages with a diameter of 3.52 meters were used. These cable baskets were only suitable for low conveyor speeds.
Improvements
With the introduction of the steam engine as the drive machine for shaft conveyance , conveying speeds of up to 13 meters per second were achieved. Cylindrical cast iron rope baskets were now used. The baskets weighed about 1.2 tons and were either cast in one piece or made from several parts and put together. In the middle of the rope cage there was a cast iron hub with wrought iron rods attached. These wrought iron bars were used to carry the cast iron wreath and to connect it to the rope cage hub. The wreath was used to hold the hoisting rope. So that the hoisting ropes could not be damaged by the rough cast iron surface, a groove was carefully turned into the rope support surface. Larger rope baskets were usually made from two discs. The two discs were made of cast iron and flanged on the inside. Planks three to three and a half inches thick were bolted onto the flanges. The windings for the hauling rope were turned into these planks. The rope baskets were stored in bearings with bronze pans. The cable cage was driven either directly by the flywheel shaft or via an intermediate gear. The rope baskets were five to seven feet in diameter . In order to be able to drive high conveying speeds with the powerful hoisting machines, it was necessary to make the diameter of the cable cage very large. For example, a rope basket 18 feet in diameter and 9 feet wide was used on the Pelton Pit at New Castle. A rope cage 24 feet in diameter was deployed at the Monkwearmouth Pit.
Modern drums
Welded constructions are predominantly used in today's drums. Mainly cylindrical drums are used. There are single drums and double drums. Double drums are available with a fixed drum and a lottery wheel, as well as with two lottery drums. The loose drums are connected to the drive shaft as cable carriers via a hiding device. The width of the drums depends on the rope thickness, the rope length (depth) and the number of rope lengths. The diameter of the rope drum depends on the rope diameter and the driving speed. The drum diameter must be at least 80 times the nominal rope diameter at speeds of more than four meters per second. The drums must be fitted with flanges to limit the rope run. The flanged disks are intended in particular to prevent the rope from jumping down to the side when the rope is slack. For particularly great depths, Blair drums are used today. A Blair drum (named after its inventor Robert Blair) is a cylindrical drum that has two separate winding areas. This allows two hoisting ropes to be wound separately on the drum without influencing each other. Two such Blair drums are required for two-drum promotion. The two drums are coupled either mechanically or electrically.
- Overview of drum types
Single drum
Double drum
conical drum
Spiral drum
Blair
Individual evidence
- ^ A b c Heinrich Veith: German mountain dictionary with evidence. Published by Wilhelm Gottlieb Korn, Breslau 1871.
- ^ Julius Weisbach: Textbook of engineering and machine mechanics. Third part, printed and published by Friedrich Vieweg and Son, Braunschweig 1851–1860.
- ^ A b Emil Stöhr, Emil Treptow: Basics of mining science including processing. Spielhagen & Schurich publishing house, Vienna 1892.
- ↑ a b J. Niederist: Fundamentals of mining science. kk court book and art dealer FA Credner, Prague 1863.
- ↑ Karl Karmarsch, Friedrich Heeren: Technical dictionary or handbook of business customers. First volume, published by Gottlieb Haase Sons, Prague 1843.
- ^ Franz Rziha: Textbook of the entire art of tunneling. First volume, published by Ernst & Korn, Berlin 1867.
- ^ Carl Hartmann: Vademecum for the practical miner and smelter. First volume mine operation. Publishing house by Richard Neumeister, Leipzig 1859.
- ^ Carl Hartmann: Handbuch der Bergbaukunst. Second volume, Verlag Bernhard Friedrich Voigt, Weimar 1852.
- ^ Gustav Köhler: Textbook of mining science. 2nd Edition. Published by Wilhelm Engelmann, Leipzig 1887.
- ↑ a b Amadee Burat, Carl Hartmann: The material in the coal mining. Published by August Schnee, Brussels / Leipzig 1861.
- ↑ a b Journal for the mining, metallurgy and saltworks in the Prussian state. Ninth volume, published by the royal secret upper-court book printing company, Berlin 1861.
- ↑ Siemag TECBERG, Drum Carriers Examples ( Memento of 14 August 2010 at the Internet Archive ) (accessed on 30 October 2012).
- ↑ Technical requirements for shafts and inclined conveyor systems (TAS) page 11/6 Definitions . (accessed June 9, 2011).
- ↑ Technical requirements for shaft and inclined conveyor systems (TAS) Section 3.3.7. + 3.3.8. Rope carrier.
- ↑ Heinz Pfeifer, Gerald Kabisch, Hans Lautner: Fördertechnik. Construction and calculation, 6th edition, Springer Fachmedien, Wiesbaden 1995, ISBN 978-3-528-54061-6 , pp. 10-22.
- ^ Howard L. Hartman, Jan M. Mutmansky: Introductory mining engineering. Wiley-Interscience Publication, 1987, ISBN 0-471-82004-0 .