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Press Release – December 2006

"Terbunsky Gontschar" Facing Brick Factory

[December 2006] KELLER HCW GmbH has set up the new facing brick factory 000 "Terbunsky Gontschar" in the Central Russian village Terbuny, which is located approx. 450 km to the south of the capital city Moscow.

The facing brick factory was designed by KELLER HCW GmbH in Ibbenbüren-Laggenbeck and Rieter-Werke in Constance, in cooperation with the Russian "Belpromproject" Institute in Belgorod. The order for the complete plant was placed by "Atomenergomontag", Moscow. Special attention is made for the personal support of the Governor of the Lipezk region, Mr. Korojov Oleg Jurewitsch, to provide the mainly agriculturally-oriented population with high-quality construction materials.

In the presence of the President of the Federation Board of the Federal Assembly of the Russian Federation, Mr. Mironov Sergeij Michaelowitsch, the Governor of the Lipezk region, Mr. Koroljov Oleg Jurewitsch, as well as important representatives of the Lipezk region and the Raijon Terbuny, and by the investor, Mr. Silivanov Michael Alexejewitsch, the Brick Factory was inaugurated on October 4, 2006.

The clay material is taken from a clay deposit near to Kasinka, approx. 15 km from Terbuny. The clay deposit was formed in the Paleozoic era, during which time Davon marine sediments and continental sandy-clay rocks of carbon arose. Sedimentation began again in the Jurassic period and continued up to the Upper Cretaceous Stage. These layers are covered by the continental deposits of the Tertiary and Quaternary formation. The brick factory is operated with an output of 40 Mio. standard bricks per year for the reference size 250 × 120 250 × 65 mm, with a perforation of 27%. For the production of 40 Mio. standard bricks per year approx. 450 t/d of clay material are required.

Project Data:

Working time:
50 weeks / year
6 days / week
2 shifts / day
7.5 hours / shift (effective)

Output of reference size:
40,000,000 standard facing bricks / year
800,000 standard facing bricks / week
114,285 standard facing bricks / day
8,890 standard facing bricks / hour

Reference size of the standard facing brick according to GOST No. 7484-78 and EN 771-1.

1. Standard facing brick 250 250 × 120 250 × 65 mm with a perforation of 27%.

Additional sizes:
2. Standard solid brick 250 250 × 120 250 × 65 mm without perforation
3. Block 250 250 × 120 250 × 88 mm with a perforation of 35%
4. Block 365 250 × 240 250 × 238 mm with a perforation of 50%

Clay preparation and shaping plant

The raw materials are fed to two box feeders by means of a shovel loader. They are then conveyed to the preparation plant via a belt conveyor. The speed of the bucket conveyor drives can be continuously controlled by frequency converters. The material is conveyed to the grinding pan by means of a belt system and metal parts are sorted out and removed by a metal detector and a reversible sorting belt arranged upstream.

By means of a central material feed, the material is fed to the inner runner in the grinding pan, which has solid plates for pre-crushing, before being moved to the outer runner, which has perforated plates. Here it is crushed again and pressed through the perforations onto the counter rotating collecting plate below the grinding pan to be fed via a belt to the next grinding stage. Continuous material humidity is achieved by means of a humidity, measuring and control system, which controls the water addition to the grinding pan.

In the following fine roller mill the material is further crushed to a grinding gap of approx. 2.5 mm. By a material distributor, directly in front of the roller mill, the material is constantly distributed onto the rollers to avoid irregular wear. Automatic turning tools for roller shells with small cutting plates are provided.

The final grain size of 1.0 mm is achieved by the following high-capacity fine roller mill with mono-cradle.

The preparation machines are connected to a de-dusting plant. The collected dust is added back into the mix from the dust filter to the material flow on the belt.
The finish prepared material is fed to the soaking house, or alternatively directly to the shaping plant, via a belt system.

In the soaking house the mass is stored intermediately in six soaking bins to pass the maturing process so that continuous plasticity of the mass can be reached during shaping. The material is fed by a computer controlled belt system to achieve a homogenous mixing of the material in the bin. The operating mass is removed from the soaking house to be fed to the shaping plant by a computer controlled automatic longitudinal excavator.

The shaping plant starts with the box feeder serving as a material buffer between preparation and shaping plant. A further metal detector is installed in front of the shaping group to eliminate metal parts, thereby avoiding unnecessary wear of the machinery.

The material is again mixed thoroughly in the circular screen feeder, the final humidity is achieved and the material is pressed through pushing plates and fed to the extruder group. Humidity is controlled by an automatic humidity measuring and control system by measuring the pressure head pressure and the power supply on the extruder worm.
The material is mixed again in the vacuum double shaft mixer, de-aerated in the vacuum chamber and fed to the worm extruder. At the outlet of the mixing chamber the mass of the mixer is shredded into small pieces by rotating knives and a tooth comb to ensure fast and careful aeration.
In the worm extruder the compacted material is fed to the die via the pressure barrel and pressure head to carry out the first shaping step (length and width of the brick). The brick height is defined in the following cutter system.

Machinery for brick production

Brick production
Products are cut from the continuous clay column by the following cutter. Depending on the type and size, 1 to 3 products are cut in each working cycle. Different cutting thicknesses can be adjusted on the changeover to another size. Blocks are turned by 90° to direction of transport in the turning device.
The waste produced on start of operation and changeover to other sizes is removed via a conveying belt system and fed again to the production line. A column swivelling crane is installed in the extruder area for exchange of dies and wearing parts.

Brick and pallet transport
After cutting the products are automatically collected into groups, transferred to the automatic pallet loader and are set down on pallets. The loaded pallets are conveyed to the vertical conveyor by means of a horizontal chain conveyor.

In the vertical conveyor one row of loaded pallets is collected in 14 layers one over the other. In the gathering frame five rows are stored intermediately one behind the other and are made available to the finger car.

The products are conveyed to the dryer by means of an electrically driven rail-borne finger car. Lateral shifting of the finger car in front of the drying chambers is carried out by an electrically driven and rail-borne transfer car. The vehicles are operated by a driver on the finger car.

After drying, the pallets loaded with dry products are removed from the chamber, in parallel with the wet side, and fed to the gathering frame on the dry side by means of the finger car. A further row is transferred to the vertical conveyor feeding the separate pallets to the pallet unloading equipment.

The pallets loaded with dry products are removed from the vertical conveyor by means of a horizontal conveyor and are conveyed to the setting plant. Only each second layer in the dryer is loaded when producing blocks. The un-required pallets are collected and stored in an automatic pallet loader.

Dryer plant

In order to ensure a high standard, the dryer plant is designed as a chamber dryer. The dryer consists of independently working operating units (double chambers) allowing for a very flexible production of different sizes and types of bricks.

Each double chamber in the chamber drying plant is controlled separately, so that each type of brick and each size can be dried with its optimum drying programme. Therefore, changeovers to another size and variations in production do not have any negative influence on the drying quality. The time-dependant temperature and humidity curve (climatic guide) can be assigned separately to each double chamber and adapted optimally to the corresponding chamber load.

Because of the independently working double chambers in the chamber dryer, drying and production errors can be immediately recognized and eliminated. Therefore, by using a chamber dryer, especially in case of difficult raw materials, drying risks in regard to reduced output and inferior quality can be reduced considerably.

The pallets are conveyed to the chambers and are deposited on supporting bars by the semi-automatic finger car. After loading, the doors of the double chambers are closed and switched to the drying process.

Drying is effected on the principle of circulation, i.e. the air inside the operating units is circulated until it has reached its highest possible moisture content and is then fed into the open air. Due to its design and being equipped with appropriate measuring devices, this dryer enables precise control and supervision of the drying climate.

The warm air required for drying is pressed by a radial fan into the main duct above the drying chambers. This duct is equipped with air control dampers for the distribution of air into the separate drying chambers. The saturated air is removed through ducts connected to a wet air stack. The wet air outlet is provided at a height of approx. 10.00 mm above ground. Axial fans installed in the wet air chimney remove the wet air.

Supply of warm air and the removal of wet air are effected programme-dependently via a process computer according to the respective type of product. The heat recovered from the tunnel kiln is mainly used for optimum utilization of energy.

Each operating unit of the dryer is equipped with an air circulation system with fans circulating the air inside the drying chambers. The chambers are heated by heat recovered from the existing tunnel kiln as well as by an auxiliary natural gas burner. The burners are designed as two-stage burners.

The temperature in the drying chambers is max. 100°C. Temperature probes are provided so that the temperature in the separate chambers can be monitored and logged.

The plant is automatically operated with a process computer system. During the loading of chambers and emptying after drying, the air control valves are closed and the fans are switched off so that no hot air can enter the respective chambers. Emptying of the chambers is carried out by finger car and transfer car.

Setting plant

The dry bricks are automatically set on tunnel kiln cars according to predetermined setting patterns by the setting machine.

The setting plant consists of crane-way, driving gear with lifting gear, gripper frame and four turning grippers. The products grouped on the pallets are removed by the setting machine grippers and transported to the kiln car by means of a driving gear. In the next cycle four product layers are removed from the pallets. During transport to the kiln car the setting grippers are turned by 90°.

By the alternating the setting of turned and non turned layers, a firing pack with cross-bond setting is formed on the tunnel kiln car. The packs are loaded 12 layers high.

Kiln plant

A pre-heater, designed as entrance sluice, maintains the constant pressure profile in the inner kiln. Flue gas and air flows are controlled by pressure distribution.

Heating of the kiln is mainly effected from the tunnel kiln ceiling. The fuel – natural gas – is fed to the kiln through feed holes by means of a burner plant consisting of several burners.

High-velocity burners with ignition and flame control are installed in the kiln walls in the heating-up zone. These burners are equipped with a central combustion air supply system.

In the firing zone, burners are combined to one burner group over two rows of feed holes. The ceiling burner plant consists of an injector burner system. The injector burner system is designed with common gas and air supply. At their inlet all burner groups are equipped with a valve system to ensure that the burner group is switched off during the pushing process or in case of failure. The tunnel kiln is divided into three classical zones: preheating, firing and cooling zone.

For cooling fresh air is pressed into the firing channel by a fan at the end of the kiln and is guided through the fired bricks. Some of the heated air is sucked off and supplied to the dryer. The remaining cooling air flows through the firing zone.

Heating of the tunnel kiln is mainly effected in the centre of the firing channel (main firing zone). The hot flue gases flow from the firing zone through the kiln load towards the inlet end of the kiln, heating up the products (pre-heating zone). Side burners are installed for additional heating.

The cooled flue gases are sucked off at the inlet end of the kiln and are conveyed into the atmosphere by the stack.

The entire kiln plant is equipped with automatic measuring, control and regulating systems. A process computer is used for process control.

Unloading – Pack-forming

The fired bricks are removed from the tunnel kiln cars in packs by means of the unloading gripper and are set down on pallets. One dispatch pack consists of eight brick layers. By means of the unloading gripper remaining layers are combined to complete packs. The unloading gripper and the automatic film hood machine are designed so that other complete fired stacks (approx. 1,440 mm high) can be unloaded and packed.

In the pack-forming area the empty dispatch pallets are automatically delivered by a pallet gripper, removing one wooden pallet from the pallet stack for setting down on a chain conveyor. Several pallet stacks can be made available on a single magazine conveyor.

When gripping the pack, the upper pack layer is pushed together. Because of this, the dispatch pack is further stabilized. The finish packed pallets are then conveyed on the chain conveyor through the packaging equipment, in which the packs are automatically provided with film hood for safe transport and are then shrunk.

The packs are then taken up from the magazine conveyor by a fork lift truck and are loaded on a truck or put into stock.

Further information can be found under the following links:

Press Release 09/2005 »

Project data of the plant »

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