ELECTROMAGNETIC STIRRING OF MELT
Electromagnetic stirring – is a technology of noncontacting exposure of variable magnetic current to aluminum melt in furnaces and mixers in order to stimulate melting processes of a bulk charge and fast equalizing of a chemical composition during alloying process.
On introduction of improvements, the test object "Mobile rectifier for manual arc welding VDU-2500" manufactured by Rezonans, LLC, passed the test according to the "Acceptance testing programs and techniques"... The Commission allows Mobile rectifier for manual arc welding VDU-2500 to be used under the conditions of the existing Reduction Area of RUSAL Krasnoyarsk, JSC. Read...
This design is resistant to mechanical damage and almost completely excludes insulation fibers and shell fragments impurities in the melt. Three months of operation proved that there are no traces of the shell, mesh or internal insulating filler destruction. Mats tightly adhere to upper clamping plates of the metal track. Read...
It was the first experience within RUSAL group to install the frequency drive based on IGBT transistors to supply power to the inductor. No breakdowns were detected in the whole period of operation of power transistor modules... Unlike the electromagnetic stirrer previously installed on Furnace No. 8, the stirrer manufactured by Rezonans, LLC, generates no strong vibrations on the surface of the melt. Thus, the oxide film on the surface remains undamaged, and mixing progresses in the normal mode... Operation of the complex proved automation resistance to nonlinear distortions of the plant networks, efficiency and ruggedness of the cooling system, as well as a good maintainability and durability of electromechanical parts. Read...
Advantages of Al-Flex: 1) mounting on the existing holding furnace outlet nozzle; 2) cleaning is not required after casting; 3) no need to treat with boron nitride; 4) quick to replace; 5) custom-design production to the furnace parameters... Hours of operation with samples (flexible connector) is as follows: Sample No 1 – 21 casting cycles; Sample No 2 – 20 casting cycles; Currently used material (1.5 meters of needle-punched material, thickness of 20 mm) – 15 casting cycles. Read...
Practice has shown that preliminary heating ensures faultless start of casting and ceramic foam filter filtration throughout the whole area. Specifically, it is worth noting the simple and efficient heating system that enables to protect heating elements from excessive heat exposure and their further breakdown. The service life of heating elements increases considerably... In the course of operation, the covers' design proved to be convenient, balanced, and good serviceability. The steady-state compressed air cooling system has high reliability to minimize the human factor. Solutions of the kind can be duplicated to heat filters and chutes in other units. Read...
Before the washing, all the 7 channels of nonmagnetic plate in the electromagnetic stirrer showed uneven water flow and admixture of deposits ... All the channels were cleaned after 6 hours washing... After the return of the stirrer into operation on completion of the maintenance, the water supply system of the plate was restored. The water flow was stable and even in all 7 channels... Recurrent washing of nonmagnetic plates in electromagnetic stirrer ensures the increase in their service life and reliable flawless operation subject to the low quality of circulating water. Read...
1.5-month testing allowed to determine that the BUT(БУТ)-3/UУ1 Thyristors Control Unit is stable in operation under conditions of the plant network. No power outages were detected… Meterings of amperemeters show no power surges or failures, current is stably maintained. Bus connection in case of a low-quality network also had no affect on the operation of БУТ-3/У1… БУТ-3/У1 is recommended for use in casting lines of RUSAL Krasnoyarsk, JSC, as a full replacement of control unit ПН-TT of both new and old designs.. Read...
EFFECT ACHIEVED BY ELECTROMAGNETIC STIRRING:
- Increasing in furnace productivity up to 25%
- Fuel saving up to 15%
- Decreasing in slag-making up to 25%
- Equalizing of temperature and chemical composition up to 1-2%
- Automation of the melt preparation process
- Expansion of alloy range
The uniqueness of electromagnetic stirrers manufactured by our company:
- A power supply based on the overall industrial frequency convertor
- Application possibility for furnaces with a capacity of up to 5 tons
- An original inductor’s construction with optimal weight-size parameters
- Customized modes of stirring settings
- A reliable and highly effective system of inductor’s air cooling with dust extraction
- Air cooling of conductive parts with reliable dust extraction systems that are maintenance-free during the whole period of the device operation (7-10 years)
- A short pay-back period for furnaces with a capacity of up to 5 tons
- One portable stirrer can supply 2 or more furnaces/mixers
- Low operating costs
Types Of Equipment
BOTTOM-MOUNTED ELECTROMAGNETIC STIRRER
- Tilting mixers or furnaces with no lift table (an inductor is moved to the working area when a mixer/furnace is in an elevated position)
- Fixed mixers/furnaces with a lift table
- Tilting mixers/furnaces with a lift table
- Several fixed or tilting mixers/furnaces with a movable inductor located on a lift table
SIDE-MOUNTED ELECTROMAGNETIC STIRRER
- In cases when construction does not allow to install more effective electromagnetic stirrer in a horizontal position under the bottom of the furnace
- In cases when during the furnace operation a necessity of increasing its effectiveness or upgrading to new alloys with higher value-added arises
- In cases when a bath’s geometry or technology of an alloy preparation requires an installation of an electromagnetic stirrer on one of the sides of a furnace