Kind Chaudron Method
The Kind Chaudron Method , also known as the Kind Chaudron Manhole Drilling System, is a percussion drilling technique that was used to drill manholes . In the 19th century the method was the predominant shaft drilling method in stable, water-bearing mountains . The process was used up to a depth of 400 meters. From the middle of the 19th century, a large number of manholes were created in Europe using the Kind Chaudron method.
history
In 1849, the German engineer Kind bored a shaft in “dead water” in the village of Schönecken, near Saarbrücken. He had the shaft joints provided with watertight shaft lining. This extension was made of wood and was reinforced with iron tires. After Kind had tested the process for the first time, the Belgian engineer Joseph Chaudron began using the cast-iron Cuvelage regularly in shafts up to 3.65 meters in 1854 . Chaudron also designed the moss box that was required for the watertight seal in this process. After 1915, the Kind Chaudron process was replaced by other processes such as the freezing process or the cementing process .
Equipment and tools required
An approximately 20 meter high derrick is required for the process. A sheave for the hoisting rope is mounted on the derrick . Two displaced and braced rails are installed below the sheave, which serve as support rails for several overhead traveling cranes. There is a cable machine on one side and a drill on the other to feed the drill rods and the bucket in and out. The machines are driven by steam power . For the actual drilling, two special drills of different sizes are required. The smaller of the two drills has a cutting edge width of 1.5 to 2.5 meters, depending on requirements, and weighs up to 15 tons. The large drill has a cutting width of four to five meters, depending on the requirements, and weighs up to 25 tons. The cutting edges of the drills consist of a series of replaceable steel teeth. In order to move the drill to and fro in the shaft, the drill engages the power arm of the drill handle, which is provided with a hand control. The drill handle consists either of iron-studded oak or riveted iron parts. The drill pipe is also made of oak with iron fittings. To remove the cuttings from the sump, a mud spoon, which consists of a cylinder made of sheet iron, is used. The cylinder is 3.86 meters high and is smaller in diameter than the cutting width of the smaller drill. At the bottom of the cylinder there are two flaps through which the cuttings are let into the cylinder.
The drilling process
First, a pilot hole with the diameter of this drill is created with the smaller drill . The foreshaft will be built up to the groundwater level or at least to a depth of ten meters. To do this, the drill is raised about 0.8 meters with a rod and then dropped onto the rock . Due to its weight, the drill penetrates part of the rock and shatters it somewhat. Then the drill is raised again and turned a little horizontally. Then it is dropped again, lifted again and rotated again a little. This process is repeated about 25 times per minute. A round borehole is gradually formed. If a lot of cuttings has already accumulated in the borehole, the drill is exchanged for the spoon and the cuttings are conveyed upwards with the spoon. It is usually drilled for between three and four hours and only then spooned. After that, drilling is done alternately and then the cuttings are scooped out of the pre-shaft. When the foreshaft has reached its minimum depth, the derrick is erected directly above the foreshaft. Then the foreshaft is drilled to the required diameter using the large drill using the same principle. The following applies: the deeper the pre-shaft is drilled, the easier it is to make the watertight extension in the form of the Cuvelage. After the shaft has been drilled a few meters in its full diameter, the Cuvelage is hung from above. Then the pre-shaft must be pre-drilled again. So, in turn, pre-drilling, expansion and expansion are carried out. Since the expansion will only be carried out with a delay after the drilling work, it is imperative that the rock is stable.
Problems and their elimination
Due to the materials used, problems arose from breaking the wooden rod at the beginning. In particular, the wooden rods to which the drill bits were attached broke when they hit the bottom of the shaft. To minimize this risk, different spacers have been placed between the drill pipe and the drill bits. The slide bar is used up to a depth of 200 meters, the free fall device above 200 meters. The sliding scissor consists of a steel rod with scissor joints. It is equipped with heavier chisels than the free fall device. When using the slide scissors, the linkage suffers more than when using the free fall device. The free fall device, an invention of Kind, consists of a large leather disc that is attached to the drill rod above the chisel. With this device, the vibrations that occur when the drill hits the rock are not transmitted to the drill rods.
Individual evidence
- ↑ a b c d e f g h Carl Hellmut Fritzsche: Textbook of mining science. Second volume, 10th edition, Springer Verlag, Berlin / Göttingen / Heidelberg 1962.
- ↑ a b c d e f g Stefan Stein: Access to mineral resources, the Kind-Chaudron shaft drilling rig made mining history. In: Culture & Technology. No. 3, 1992 pp. 28-29.
- ^ Ernst-Ulrich Reuther: Textbook of mining science. First volume, 12th edition, VGE Verlag GmbH, Essen 2010, ISBN 978-3-86797-076-1 .
- ↑ a b c d Gustav Köhler: Textbook of mining science. 6th improved edition, published by Wilhelm Engelmann, Leipzig 1903.
- ↑ a b c d e f g Gustav Köhler: Textbook of mining science. Second improved edition, published by Wilhelm Engelmann, Leipzig 1887.
- ↑ a b c d e f g F. Freise: Alignment, installation and mining of hard coal deposits. Publishing house by Craz & Gerlach, Freiberg in Sachsen 1908.