CN2202899Y

CN2202899Y - Energy-saving induction furnace

Info

Publication number: CN2202899Y
Application number: CN 94223177
Authority: CN
Inventors: 王建国
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-10-05
Filing date: 1994-10-05
Publication date: 1995-07-05
Anticipated expiration: 2004-10-05

Abstract

The utility model relates to an induction furnace, which is characterized in that the bottom margin of a crucible is arranged in a range delta h below the upper edge of a first induction coil, wherein, 0< delta h< =h/4; the h is the height of an inductor. Thus magnetic field generated by the inductor is fully used; the furnace volume is enlarged; the power consumption of the utility model and the cost of bottom drop are reduced; the production is increased; the happening of accidents is reduced; the composite cost is lowered; the quality of products is improved. The utility model can be widely used for intermediate frequency furnaces and line frequency furnaces to smelt various metals.

Description

Energy-saving induction furnace

The utility model relates to a kind of induction furnace.

In the last few years, induction furnace is used widely in China's metallurgical industry, in various metals and alloy production, all play important effect, its operation principle is: produce alternating magnetic field when alternating current passes through inductor, alternating magnetic field produces induced electromotive force in the metal charge in stove, produce alternating current heat energy in order to smelting metal in metal charge, and induced field is strong more, induced electromotive force is big more, the also big more (Q=I of the alternating current of inducting ²Rt) so the heat that produces in the metal charge is many more, metal molten is fast more, the present equal following 1-2 circle of the inductor bottom coil lower limb in the induction furnace that generally adopts of China on the crucible base, as shown in Figure 1, the magnetic induction intensity that the alternating current by inductor coil produces in stove distributes, with its axial line magnetic induction intensity is representative, corresponding with the induction furnace structure, as shown in Figure 2, in Fig. 2, B represents magnetic induction intensity, μ ₀Magnetic conductivity, n coil turn, I coil current, 1 district expression crucible furnace charge district, expression high-intensity magnetic field district, 2 districts.

The magnetic induction intensity that produces of inductor is the strongest at the coil middle part as seen from Figure 2, and with magnetic induction intensity gradually far away weakens gradually from the middle part, to weaken degree of passing very big for magnetic induction intensity outside induction coil.

Can see that on Fig. 2 the crucible bottom still has the stronger magnetic field of part, does not have metal charge in this part magnetic field, is not fully used, cause the electromagnetism waste, electrothermal efficiency is low, and heat size is little.

The upper end metal charge is in than in the low-intensity magnetic field in the crucible, and induced current is little, and electrical heat energy is few, far away apart from the high-temperature region, middle part, conduct heat slow, the heat-retaining condition difference is to aerial heat radiation, and therefore upper end metal charge temperature is low, and fusing is slow, overcharge is put very little, productivity ratio is low, easily crusts blast-furnace man's operating difficulties, the etch of slag line furnace lining is serious, easily penetrates.

The middle part metal charge is in the magnetic induction intensity maximum region, the induced current maximum, and electrical heat energy is many, quick heating, temperature is high and conduct heat to two ends.

The lower end metal charge is in the high-intensity magnetic field district in the crucible, and induced current heat energy is many, and is near apart from the high-temperature region, middle part, and it is fast to conduct heat, and adiabatic condition is good on every side, and heated time is the longest, quick heating, temperature height, and the too high meeting of temperature causes heat waster and the serious etch of furnace lining.

During induction furnace melting, gap is big up and down for furnace temperature, and inductor and crucible expanded by heating are inhomogeneous, easily plays arcing between induction coil, damages expensive inductor, and economic loss is big, and the temperature difference greatly also causes the smelting metal composition inhomogeneous, influences product quality.

This structure existing problems reason is not have fully rationally to utilize the induced magnetism field energy of inductor generation.

The purpose of this utility model is to provide a kind of can make full use of the induced magnetism field energy that inductor produces, and improves the induction furnace of induction furnace electrothermal efficiency.

The purpose of this utility model is achieved in that the crucible base in the induction furnace is arranged in the following △ h of the first circle induction coil top edge scope, 0＜△ h≤h/4, and wherein h is the height of inductor.

Can make furnace charge all be in high-intensity magnetic field like this and, make full use of the induced magnetism field energy, improve the induction furnace electrothermal efficiency than in the high-intensity magnetic field district.

Accompanying drawing 1 is a disclosed induction furnace structural representation in the utility model prior art.

Accompanying drawing 2 is the magnetic induction intensity distribution schematic diagram of induction furnace in the utility model prior art.

Accompanying drawing 3 is the utility model structural representation.

Accompanying drawing

4,5 is at the bottom of the utility model crucible and induction coil relative position variable condition schematic diagram.

Accompanying drawing 6 is the magnetic induction intensity distribution schematic diagram of the utility model induction furnace.

As shown in Figure 3, the utility model comprises crucible 1 and inductor 2 etc., and crucible base 4 is arranged in the following △ h of the first circle induction coil, the 3 top edges scope, 0＜△ h≤h/4, and wherein h is the height of inductor.Accompanying drawing 4 is arranged on below the first circle induction coil, 3 top edges for the utility model crucible base 4, the position that lower limb is above, and promptly crucible base 4 is arranged on the first circle induction coil (comprising first circle) with upper/lower positions.Accompanying drawing 5 is arranged on the following h/4 place of the first circle induction coil, 3 top edges for the utility model crucible base 4, and h is the height of inductor.In accompanying drawing 6,1 district expression crucible furnace charge district, expression high-intensity magnetic field district, 2 districts, the utility model furnace charge all is in high-intensity magnetic field and than in the high-intensity magnetic field district, has utilized induced field fully as can be seen, and leakage field reduces, and heat size enlarges.

In the metal charge of upper end suitable heat energy induced electricity is arranged, simultaneously nearer apart from the high-temperature region, middle part, it is also fast to conduct heat, and it is very fast to heat up.

Metal charge magnetic field, middle part is the strongest, electric current is maximum, quick heating, and the temperature height conducts heat to two ends.

The lower end metal charge has suitable electric current heat energy, and adiabatic condition is good on every side, obtains the high-temperature region, middle part and conducts heat, and heated time is the longest, can obtain enough temperature, and accurately controlling the furnace bottom position, can to cushion charge-temperature unlikely too high, the protection furnace lining.

The utility model structure makes full use of electromagnetic energy, improve the stove electrothermal efficiency, the crucible capacity increases, and rationally overcharge improves output, furnace temperature is more even up and down, it is big to have overcome the ordinary construction temperature difference, produces crust, melts slowly, beats shortcomings such as arc, composition is inhomogeneous, the furnace lining etch is serious, and the minimizing accident takes place, reduce cost, can increase substantially economic benefit.The utility model △ h scope preferably is: 0＜△ h≤h/5.

Induction furnace adopts the utility model can not increase investment, and exchange device does not more increase under employee's the situation, and melting cost and cupola drop cost etc. descend significantly, the output increase, and its overall economic efficiency is remarkable.

Adopt the utility model structure to smelt W9 μ at the 0.5t intermediate frequency furnace ₀The 3Cr4V steel grade, 30 stove productions, under the identical overcharge amount of average furnace output 680kg situation, shortened to 3 hours 29 minutes by 4 hours 17 minutes the duration of heat with ordinary construction comparison stove, stove has shortened 48 fens the duration of heat, electric power consumption per ton steel reduces to 1100KWh/t by 1400KWh/t, reduces electric power consumption per ton steel 21%, volume increase 19%.

Claims

1, a kind of energy-conservation induction furnace comprises inductor 2, crucible 1 etc., and induction coil is characterized in that crucible base 4 is arranged in the following Δ h of the first circle induction coil, the 3 top edges scope outside crucible 1,0＜Δ h≤h/4, and wherein h is the height of inductor.

2, a kind of energy-conservation induction furnace according to claim 1 is characterized in that 0＜△ h≤h/5.