Bucket-wheel excavator

Bucket wheel excavators are machines for extraction of raw materials and for use on construction sites. Especially large bucket-wheel excavator - with dimensions of several hundred meters - are used in the lignite mining.

• 9.1 Philately
• 9.2 Art
• 9.3 Model

Braunkohlebagger

Bucket wheel excavators are among the largest and most spectacular excavators in the world and have been produced since the 1930s. Since 1978, there are excavators up to 240,000 tons of coal or cubic meter can move overburden daily. This 240.000er are still the biggest excavator in the world. The 1978 built by VVB TAKRAF Lauchhammer excavator SRs 1510 6300 in the Lusatian mining area and built the same year by Krupp Industrietechnik bucket wheel excavator " 288 " in the Rhenish mining area were the first excavator of this performance class. The excavator 288 currently operates in Garzweiler mine (RWE Power). An almost structurally identical copy of the same period of the "Bagger 289 " built by O & K ( Orenstein & Koppel ) and LMG ( Lübeck mechanical engineering company), who works in Hambach mine.

Construction of a bucket wheel excavator

A bucket wheel excavator consists of an undercarriage, a rotating superstructure and the loading device. The chassis can be configured as a crawler track or walking mechanism. On the superstructure of the wheel arm is attached at the tip of the paddle is. An important distinguishing feature is the design of the wheel boom with or without feed, which affects technical parameters (eg, structure and weight ) as well as the extraction technology.

The paddle wheel can be swiveled, tilted or both at the wheel arm axis. The pivoting of the blade wheel (around the vertical axis) is generally required in order to ensure the free- cutting angle for the side-mounted bucket wheel. The impeller is tilted (about the wheel arm axis) to improve the evacuation of the material to be conveyed.

Operation of a bucket wheel excavator

The driver swung the superstructure generally at an angle of 90 ° in the working direction and depends on the device to 35 degrees in mining direction. The impeller rotates either clockwise or counter- clockwise (depending on the arrangement of the blades ). In this case, this refers to the overburden and coal. The material is then - depending on the position of the wheel boom and level of degradation disc - transported 30 to 180 degrees upward until it by gravity to the abrasion liners ( a 45 ° inclined ramp / slide in the so-called bucket wheel ) and then onto the conveyor belt of the wheel boom ( " Radband " ) arrives, and is transported to the undercarriage. There falls a few meters deep on a second conveyor belt that leads to the loading device. The latter connects the excavator with the Strossenbandanlage of the mine, which leads either to the spreaders, intermediate storage of coal (coal bunker ) or the power plant. The unit " loading device " is firmly connected to the excavator and thus belongs to. It is either a separately controlled device (so-called hopper car, left) or - especially in smaller bucket wheel excavators in coal mining - a movable boom with dropping funnel.

Specifications of excavators

Excavator RWE Power (formerly Rhein Braun)

Excavator 258 in Garzweiler

The Schaufelradmotors:

Excavator of the Central German and the Lusatian mining district

The bucket wheel excavator in the Central German lignite mining area ( Mibrag ) and Lusatian lignite mining area ( Lusatian lignite AG - now Vattenfall Europe Mining AG) were prepared exclusively from the Combine TAKRAF. The total number of produced in the GDR and in the opencast mines of the GDR -down bucket wheel excavator used here amounts to about 155 pieces. In addition there are exports to other countries of the CMEA as well as some old digger from the period before 1945.

The main types of TAKRAF are:

• SRs 630,
• SRs SRs 702 and 704 - 2.500 m³ / h,
• SRs 1301 - 3,500 m³ / h,
• SRs 2000 - 6,000 m³ / h,
• SRs 2400 and
• SRs 6300 - 14,000 m³ / h

The SRs name stands for " bucket wheel excavator on caterpillar tracks, swiveling ". The figure defines the capacity of a single blade in liters. Since in the course of development, the performance of the excavator could be increased despite the same bucket size ( for example, faster rotating paddle wheels, longer blades and faster bands), one is later transferred to the number to detach from the blade size and to refer to a theoretical bucket capacity, which would have been used, the excavator will be constructed in a conventional manner. Thus the performance of SRs 1300 corresponds approximately to the performance of a classic digger with bucket capacity 1300 l, although the SRs 1300 only offers a bucket capacity of 700 l. Thus, for example, the largest built in the GDR bucket wheel excavator SRs 6300 type a bucket capacity of 3300 l on - while still achieving the performance of counterparts with 6300 l capacity. ( Built in 1978 Saxony) and in Welzow -Süd ( South Brandenburg, built in 1981 ) Two of these devices are used in surface mining Nochten. Another device ( DDR-Nr. 1550) of this size has gone into operation in 1988 in the mining Breitenfeld ( Leipzig area ), but was scrapped in 1996. Although its dimensions of 243 m length, 57 m width and 63 m height under which the excavator 288 (RWE Power) are, how to reach but with up to 336,000 m³ / day significantly higher theoretical capacity. This theoretical capacity is, however, rarely achieved, because this ideal situation (loose gravel, high impact, large disc height ) must be present. Flow rates of approximately 275,000 m³ / day have been however already practically achieved.

An attached to the model number "a" or "n " refers to types, of which there are (often types from the period before 1960) is an old version and a newer version.

The complete device name included in addition to the ( theoretical ) Bucket capacity nor the maximum reduction in thickness in the high and low cut, and the length of the feed and the driving power of Schaufelradantriebs. If a loading unit has been available, nor was added to specify the order bridgeable difference in height. For example, was the exact type specification for an excavator of the type SRs 1200a:

SRs 1200.24/4.12 ( 400kW )

It would therefore appear that the buckets has a capacity of 1200 l, respectively, in the high- average 24 m and the depth slice can handle 4 m thick, a 12 m long feed offers and has a Schaufelradantriebsleistung of 400 kW. From excavators of the same basic type (eg SRs 702) there were different versions, which differed from other mining widths.

Towards the end of the GDR and the opencast mines Nochten Jaenschwalde still larger excavators of the type SRs 8000 ( excavator numbers 1580 and 1587 ) were planned for use in the pre-cut. If these giants have been built, they would have been the most powerful bucket wheel excavator in the world by far. The design of these devices, however, was in the wake of the decline of coal demand dropped in the early 1990s.

The larger devices (as SRs 2000) are usually used for removal of excavated material, the excavator with the lower blade volume mostly for the extraction of lignite. Initially smaller excavator were used (for example, SRs 1200) for moving waste materials.

Excavators in the Lusatian mining area

Today there are still in the Lusatian mining area in use:

Cottbus- Nord

Mining Jaenschwalde

Mining Nochten

Mining Reichwalde

Welzow -South

Excavators in the Central German area

Mining Amsdorf

Mining Profen

Opencast United Schleenhain

Laying of brown coal excavators to another mining

To lay a brown coal digger is in another open pit, there is either an opportunity to dismantle it and reassemble, which is very time consuming, or - if no major obstacles such as rivers are in the way - simply to let him take the land. A Braunkohlebagger has a chassis, travels up to 10 m / min and is terrain. In recent years (now RWE Power AG ), the latter method was used in particular in the Rhine Braun AG.

When laying barriers of many species cause problems. For overhead lines must be removed before the arrival of the excavator and roads, motorways or railways closed and covered for protection with a thick layer of soil. Since Braunkohlebagger have electric drive, they are supplied with such actions from the 25/30-kV-Netz a retractable cable. Due to the limited length of the cable anywhere along the route clamp connectors for the leads, called " submarine " installed. After about 1000-1400 m you drive the excavator of a " submarine" needs to be reconnected to the next.

Performed excavator linings of RWE Power

Incidents in the operation

Museums

On Berzdorfer lake at Görlitz Excavator 1452 of the former opencast Berzdorf can be visited.

In the Hessian Brown Coal Mining Museum Borken is a bucket-wheel excavator. It was constructed in 1952 by the company Orenstein & Koppel Luebeck engineering company and was employed in the coal mining area of Borken in coal mining. The large extraction unit is about 14 m high and 30 m long. It is presented to visitors to the museum demonstration mode.

In Ferropolis, an open- air museum near Dessau, a whole series of discarded mining equipment be visited, including a bucket wheel excavator SRs of type 1300 ( DDR-Nr. 1521).

Furthermore, there is in mining technology park in Leipzig Lake just off the highway 38, near junction 31 ( Cross Leipzig -Süd) a settler ( A2Rs -B 10000,110, DDR -No. 1115 ) and a bucket wheel excavators ( SRs 1000n, DDR -No. 1547) to the view. (→ Karte51.24652612.421661 )

In the Adventure Mine is the biggest underground bucket wheel excavator in the world, produced by VEB mining machinery Dietlas issued.

Reception

Philately

As part of the definitive stamp series Industry and Technology of the German Federal Post a 100 - Pf - stamp was issued on May 15, 1975 Schaufelradmotiv.

Art

From Yulia Kazakova the painting comes Earthmover ( 250x150 cm, acrylic on canvas, 2009). The image of a scholarship from the Friends of the University of the Arts from 2008 to 2010 represents the excavator 288 as a typical representative of the German industrial aesthetics dar.

Model

Braunkohlebagger are also available as models. These models (kits ) were prepared in the 1980er/90er years and now have a large collector's value.