Stamp mill

A stamp mill, also called stamping mill, slotting or percussion, was one for crushing ores serving machine. Stamp mills were mostly integrated into the smelters and iron hammers. The technical director of a stamping mill called Pochsteiger. For the operation of a stamping mill a mountain regulatory approval was required. Stamp mills were used in other tamping mills, such as oil mills, Lohmühlen, bone mills, Blue color works and powder mills.

Basics

Dating from the ore mines raw ore had to be processed before melting. Some ores had such a low metal content that they first had to destroy in order to prepare them further. Such low-grade ores was called the Pochgänge. Depending scored grain size was called the respective Pochvorgang rough pounding, throbbing or Rösch fine rap. When coarse rap is achieved grain sizes between four to eight millimeters, formed by Rösch pounding the grain sizes were at two millimeters and the fine rap at one millimeter. The resulting crushed ore was called the Pochmehl or Pochzeug. If the Pochmehl was sharp, it was called the crispness witness, it was only slightly rough, it was called the mild witness. Stayed the Pocharbeiter not exactly on the Pochvorgang and the ore was pounded for too long, so the ore particles were crushed into fine flakes. These platelets were useless in the further processing, as they floated on the water and were washed away. When such particles were told " the ore has been knocked dead."

History

From a safe documented written record shows that the first Trockenpochwerke have already been used in 1492 in Scharl in southeast Switzerland. In 1512 Schwaz mining first Nasspochwerke were around the year been used. This technology was passed on to the Saxon Erzgebirge later. In Schneeberg a stamp mill was built in the years 1752-1753, with the cobalt ores were pounded. Ramingstein in Lungau mining area, there were four stamp mills in the 16th century. This stamp mills were in operation by the year 1782. In the Upper Harz, there were once numerous stamp mills for crushing the ore extracted. From Goldlauter in Suhl is known that there existed in the valley of the Goldlauter in the 16th century up to eight separate stamp mills. Therefore, the valley is called today in parts " Pochwerksgrund ".

Types

It was dry and also Nasspochwerke. Nasspochwerke were in their construction to Trockenpochwerken very similar, there were differences in the size of Pochschuhe and Pochsohle. The Pochzeuge the Trockenpochwerke were then transported for further processing in the Siebsetzung. Nasspochwerke served as it were the Erzwäsche, wherein by means of gravity separation, the bearing ore was enriched in Pochmittel. The Pochzeuge from wet throbbing were processed on the shock stove or oven to the reciprocal. From the Pochtrübe the Pochfluth was left as the remnant of the settling process. The Pochfluth contained no usable ore more. The wet process allowed for a less dangerous and cleaner to deal with the throbbing materials.

Construction

Stamp mills consist of several components. The framework of the stamping mill is the Pochstuhl, in his Pochstempel be performed. Each Pochstempel is located in a separate section. Three to five Pochstempel form a Pochsatz. Under the Pochstuhl is the Pochsohle, in this Pochsohle the ore is crushed and filled by the Pochstempel.

Pochstuhl

The Pochstuhl was constructed differently depending on the design. The heavier the stamp were, the more stable and more difficult had to be built and the Pochstuhl. In general, it was built of wood. Thus, the Pochstuhl not wandered through the shocks that caused by the movement and the breaking of the Pochstempel back and forth, he was attached with struts. In some mining districts the Pochstühle were placed on a firm foundation. For this, the top soil was removed about five to seven feet. Where this was not possible foundations of heavy beams were created.

Pochstempel

The Pochstempel were also called Pochschiesser. As Pochstempel timbers were used mostly made ​​of hard wood with a thickness of six to seven inches. To guide the Pochstempel two Leithölzerpaare were used which had to be mounted in a precisely tuned height on the side of the woods Pochstuhls, the Pochsäulen. The upper Leitholzpaar have been placed too high above the Pochsohle, then had the Pochstuhl to have a sufficient level, be provided with additional side supports. In Nasspochwerken the lower Leitholzpaar could not be mounted too close to the Pochtrog because it loses the high splashing water on abrasion resistance and wore out faster by moving Pochstempel. The bottom of every Pochstempels an iron ring, Pochschuh or Pocheisen was called, fixed. The Pochschuh subject to high wear and was therefore replaced. Thus the Pochschuhe had a long life as possible, they were made ​​of hard materials, usually was the extra- hard cast iron, steel. In order for the stamp on impact with the ore had a large enough impact force, he had to be positioned in Pochstuhl that he hit from a mean drop of eight inches on the material to be comminuted ore. The drop height of the Pochstempels was adjustable and should not be higher than twelve and not less than four inches. The weight was per Pochstempel between 100 and 500 pounds. Easier stamp were less suitable, because then more per stamp stamp mill needed for the same Pochleistung. Heavier stamp were not suitable because they were more difficult to handle and had to be conditionally stable design of the lifting parts stamping mill by their weight. The mean weight of the stamps used was about 300 pounds.

Pochsohle

The Pochsohle formed the bottom of the stamping mill, the ore was crushed on her with the Pochstempeln. The Pochsohle had to possess a great strength and hardness. The material usually called " halved " cast iron was used. The Pochsohle was more durable than the Pochschuhe usually. There square plates were used, which could be used on both sides and up to four times folded. Was a page worn, the individual panels of Pochsohle were reversed. The material used for the Pochsohle had a maximum thickness of four inches. Stronger material was not required because the wear of material per side did not exceed 1.5 inches. The length and width of the Pochsohle was dependent on the dimensions of the Pochschuhe. The cast-iron Pochsohle had to be placed on a flat surface. In general, this cast iron plates was also used. However, these plates had a thickness of at least six inches, if necessary, up to twelve inches. These larger material thicknesses were required in order to counteract the vibrations caused by the stamping of the Pochstempel. There was Pochsohlen prepared from very hard stones, these are summarized in wooden boxes. This stone soles were repair resistant and lighter, the stones had been flattened, new stones were refilled. However, the stones could become confused even when rap and Pochsohle stone needed a deeper base than the Pochsohle of cast iron.

Pochtrog

In Nasspochwerken a Pochtrog was installed instead of the Pochsohle, he had the same task as the Pochsohle. The Pochtrog was made ​​of oak or beech wood. The trough had as well as the Pochsohle have a solid base. Was the ground too soft a foundation of wooden planks was created. Thus, the Pochtrog was tight, the joints between the timber were sealed with thin towels or moss. On the side of Pochtrog had an opening from which the batch was run out of the crushed ore and water. The filled for the Pochvorgang in the Pochtrog water called the hut man Pochwasser, the ore - water ( suspension) he called Pochtrübe. At the Pochtrog was an assembled from three wood form, the so-called flume built. At the end of the channel was a Absetztrog, which was designated as the bottom. The Pochtrübe flowed from the Pochtrog over the flume into the swamp.

Drive

The stamp mill was usually driven by a water wheel. There were also stamp mills that were driven by animal muscle strength or later with a steam engine. The prime movers were hitched to the Pochwelle that stood out from the Pochstuhl. This shaft was provided with recessed pins, so-called Heblingen. This in turn Heblinge operated so-called Tom Thumb, which were provided with a mechanism by which the stamp of the stamping mill were moved.