Metalurgy

Pragokor ALMAG 630 is a salt for both covering and refinement of the Al – Mg alloys at the temperatures as low as 630 °C, suitable for the alloys of the magnesium content as much as 11%, at the remelting process with a subsequent refinement. The agent is able to protect the smelt against undesirable burn-off and dissolves aluminium oxide.

Way of use:

The metal charged into the furnace should be covered with a spilled layer of Pragokor ALMAG 630 in the concentration of 0,5 – 1 % (related to the whole charge). After melting of the charge, the same amount of the agent should be added again and stirred with a bell into the whole batch. After 5 minutes of the dead melting, the slag may be skimmed off and the charge cast.

Pragokor ALSIL 412 is a refining salt suitable for an intensive cleaning of melted aluminium, especially in the gas-heated furnaces, which creates a dry and powder-like slag at the chemical reaction with aluminium oxide. Due to the chemical reaction, the slag itself is a bit self-heating and retains only a minimum amount of metal which may readily evaporate and, therefore, loss in the metal refined is reduced substantially.

The agent should be used for the refinement of aluminium and its under-eutectic alloys with silicone and copper being processed in the gas-heated furnaces where otherwise a local overheating of both the smelt as well as slag might occur. Unlike Pragokor Alsil 412, current refining salts may be locally overheated inside the furnace and, consequently, may retain much metal to be refined.

Way of use:

At the temperature 680oC, the agent should be sprinkled onto the surface of the smelt in the concentration 0,1 – 0,3%, calculated on the total amount of the processed metal and, after a delay, immersed and stirred into the melt with a bell or scraper. The slag created will float up onto the surface and will separate readily.

Pragokor ALSIL 680 is a salt for the refinement of melted aluminium and its alloys. Due to its positive affect, all impurities may be readily bonded into the slag.

The agent is especially convenient for the refinement of the smelt of aluminium and its under-eutectic alloys with silicone and copper if casting into the metallic moulds or the pressure die casting at the temperature range 670 – 700 °C are required.

Way of use:

The agent should be sprinkled onto the surface of the smelt in the concentration 0,5 – 1%, calculated on the total amount of the processed metal, and stirred carefully into the charge with a scraper. After a while of 10 minutes, the residues of the agent will flow up onto the surface from where they should be removed and the metal may be cast.

Pragokor ALSIL 710 is a salt for the the refinement of melted aluminium and its alloys by the affect of which the impurities and oxides in the smelt are converted into slag.

The agent is predominantly suitable for the refinement of under-eutectic alloys of aluminium with silicone and copper if casting into metallic moulds or the pressure die casting at the temperature within 705 - 725°C are required.

Way of use:

The agent should be sprinkled onto the surface of the smelt in the concentration 0,5 – 1%, calculated on the total amount of the processed metal, and stirred carefully into the charge with a scraper. After a while of 10 minutes, the residues of the agent will flow up onto the surface from where they should be removed and the metal may be cast.

Pragokor ALSIL 750 je rafinační sůl k čištění roztaveného hliníku a jeho slitin. Jeho působením se nečistoty a oxidy převádějí do strusky.

Pragokor ALSIL 750 is a salt for the refinement of melted aluminium and its alloys by the affect of which the impurities and oxides in the smelt are converted into slag. The agent is predominantly suitable for the refinement of under-eutectic alloys of aluminium with silicone if casting into sands moulds at the temperature within 725 - 760°C is required.

Way of use:

The agent should be sprinkled onto the surface of the smelt in the concentration 0,5 – 1 %, calculated on the total amount of the processed metal, and stirred into the charge with a scraper. After a while of 10 minutes, the residues of the agent will flow up onto the surface from where they should be removed and the metal may be cast.

Pragokor ALSIL 2841 is a salt for the intensive refinement of aluminium smelt from where gases are being evolved simultaneously. The gasses facilitate the stirring of the agent into the whole volume of the batch better than a mere mechanical charge agitation with a scrape or a bell. The slag floated up will bond all impurities and oxides which causes a marked improvement of refining affect of the agent. The slag resulted is dry and powder-like.

The agent is predominantly suitable for the refinement of under-eutectic alloys of aluminium with silicone and copper if the pressure die casting is required.

Way of use:

Depending on the degree of the batch oxidation, the agent should be sprinkled onto the surface of the smelt of the temperature at least 650 °C, in the amount of 0,05 – 0,2 %, calculated on the processed metal and, after a while, emerged onto the bottom of the foundry ladle with a bell. The gases being evolved will get ignited and burn out. After the gas evolution, the smelt should be stirred with a scrape carefully which will release the residual slag entrapped. Consequently, it will float up and may be skimmed off easily. The refined metal is ready for the discharge into the holding furnace placed by a pressure die casting machine.

Pragokor PUR 1 is a salt which facilitates removal of undesirable aluminium oxides stuck onto the walls of the furnaces at the melting process. This firmly embedded layers are formed of mixture of aluminium oxides continuously being converted into hard corundum very difficult to be fused. The Pragokor PUR 1 agent is able to etch corundum and convert it for a soft dough-like substance. The agent is especially suitable for the gas-heated melting furnaces which are more liable to form accretions on the furnace walls.

Way of use:

The heated furnace walls covered with the accretions should be spilled with the agent which will be melted onto them. The smelt formed will make the accretions more soft and, consequently, after several repeated applications, particularly in the cases of thicker deposits, may be easily removed.

Pragokor T 3 is a refining salt with a modifying affect on the purification and adjustment of under-eutectic Al-Si alloys at the temperature within 730 – 780 °C.

Way of use:

The charge should be refined with Pragokor ALSIL 283 at first. The slag must be skimmed off from the surface and, afterwards, 1 – 2 % of Pragokor T 3 (calculated on the whole charge) should be applied onto the smelt surface. After a while, the agent should be immersed towards the bottom as low as possible and stirred into the charge with a bell. The residual slag will rise onto the surface from where should be skimmed off after about 5 minutes. As for the casting process, the thin-walled and thick-walled casts must be made within 20 minutes and 15 minutes respectively. After that, the whole modification process should be repeated with the half salt concentration.