Melting and Holding Furnaces for Die Casting & Foundry Applications
An important consideration when selecting melting and holding furnaces is the source of fuel. To achieve high melt quality, gas fired with a side exhaust gas discharge is a great choice. The trade-off for high melt quality using gas fired results in reduced energy efficiency. Fuel-fired furnaces with heat recovery recuperation can provide high melt quality and reduce energy costs up to twenty-five percent.
If the energy efficiency and melt quality are the main objective, electric furnaces are the best option. Electric heat has the better to control of the heat to provide a more precise and consistent heat. In addition, the melt is not contaminated by emissions from a gas-fired heating. Although electrically heated furnaces have ten to twenty percent reduced melting performance, the energy costs are considerably reduced. Electric furnaces are quiet and environmentally friendly, producing zero flue emissions from the on-site energy source. Electric furnaces are as contamination free as the material being melted.
There are several types of furnaces that are used for melting and holding in the die casting industry. These include: reverberatory, crucible, immersion, dosing, induction, and stack furnaces.
Reverberatory furnaces use gas fired burners or electric coils mounted in the sidewall or other areas of the furnace to melt the metal. Reverberatory furnaces are commonly used in aluminum die casting applications. Gas fired reverberatory furnaces are used in applications where large amounts of molten metal can guarantee a steady supply of molten metal for high volume die casting operations. Reverberatory gas fired furnace capacities can range up to 150 tons. Reverberatory furnaces are typically used in high volume processing.
Crucible furnaces are one of the oldest forms of melting unit used. Crucible furnaces are typically used where small batches of low melting point alloys are involved. The furnaces use a refractory crucible which contains the metal to be melted. Classification of crucible furnaces is according to the method of removing the metal from the crucible, including: Tilting, Lift-out and Bale-out.
Immersion furnaces have a tube that is submerged in the molten metal. The tube is either gas charged or electrically heated. Immersion furnaces are common used for metal alloys with lower melting temperatures. An advantage of gas fired immersion furnaces is the fact that the combustion gases are not exposed to the molten metal, reducing oxidation losses and reducing contamination to the molten metal.
Dosing furnaces are enclosed holding furnaces with a spout to deliver the exact amount of molten metal to the die casting machine. Because the furnace is enclosed, it reduces heat loss and protects the molten metal from contamination. Dosing furnaces are eighty per cent more efficient to store a ton of aluminum as compared to open crucible furnace. Dosing furnaces are typically used in holding applications where precision and energy saving are required.
Induction furnaces boast reduced emissions and melting efficiencies from fifty percent to seventy percent. Induction furnaces come in two varieties: channel induction and coreless induction. Channel induction furnaces use an 60 cycle electromagnetic field to induce the metal to flow between two electrical resistance coils. This creates an even and consistent temperature throughout the molten metal. Coreless induction furnaces heat the metal through an external coil and are typically used to melt shredded scrap metal. Induction furnaces tend to be more expensive initial investment, operating and maintenance costs.
Die Cast Machinery, LLC is the global leader in procurement and sale of second hand melting and holding furnaces. If it exists in the world of die casting we have it or can find it. We offer comprehensive services which include: facility appraisals, financing, plant liquidations and sales of ongoing businesses. We are a service orientated company that is dedicated to help you find the right machine for your application and budget offers used, second hand high pressure die casting machines in cold chamber and hot chamber configurations.
Die Cast Machinery, LLC buys and sells used furnaces for melting and holding Aluminum, Magnesium, Zinc, Zamak and other metal alloys used in the high pressure die casting and non-ferrous foundry industries. Major brands we sell include: Striko shaft melting furances, Westofen dosing furnaces, Westomat, Dynarad, Rayteq, Thermaltek electric resistance crucible type furnaces, Lindberg/MPH, FW Schafer, reverberatory (reverb) furnaces, Modern Equipment stack furnaces including the Modern Jet Melter; Stotek, Thermtronix, Cal-Miser, Seco Warwick, Ajax Tocco, Rauch, Metamag, Nabertherm and others.
Furnace types include Tower melters, Stack melting, Shaft Melting, Reverberatory melting, Induction melting, Dosing furnaces, launder systems for hot metal delivery, low energy high efficiency radiant furnaces; glow-bar furnaces and immersion furnaces. We Buy and sell second hand high efficiency gas fired Stack Melter, Shaft Melter, Tower Melting, Reverberatory, Immersion tube, Crucible and Electric Induction type furnaces and related equipment. Energy sources include fossil fuels (natural gas fired, oil fired, liquid propane (LPG) and electric heated furnaces such as induction and resistance furnaces.) Major manufacturers from Europe: Striko Westofen, Stotek, Nabertherm, Meltec; from North America Modern Equipment, Lindberg/MPH, Cal-Miser, Dynarad, F.W. Schaefer, Seco Warwick, Thermtronix and Metamag. Other furnace builders include: Hi-TEQ, Striko-Dynarad, Thermaltek, Inductotherm, Unitherm, Ajax, Gasmac others.