The furnace is ideal to melt precious metals. All ITALIMPIANTI ORAFI induction melting furnaces are
fitted with static frequency converters.
A high efficiency of the electrical output that drastically reduces electricity consumption, maintaining the
production rate, is obtained by the frequency conversion system used.
The modular construction of the electric circuit board greatly simplifies maintenance operations and
guarantees high reliability even in the most demanding working conditions.
The highest technical standards used to design the inductors along with the modular construction and the
use of only high quality materials guarantee maximum production even in the worst conditions.
Technical data of the furnace
- Capacity of the crucible : 110 kg of Ag or 170 kg 18 ct Au
- Melting time : 20 minutes
- Interchangeability of the crucible to melt different precious alloys
- Automatic temperature control of the metal with a platinum, 10 % platinum-rhodium thermocouple
- STATIC FREQUENCY CONVERTER
- Nominal power M.F. 150 kW
- Working frequency 4 KHZ
- Max voltage M.F. 800 V
- Power of connection to the plant 190 kVA
- Power supply voltage (3 Phase/50 HZ) 380 V ±6%
- Power factor (cosF-i) 0,9 c
- THREE-PHASE POWER SUPPLY TRANSFORMER
- Nominal power 190 KVA
- Primary nominal voltage of power grid (+-2,5+5%)
- Secondary voltage loadless 400 V
- VCC% min. 5%
THE CONVERTER IS MADE UP OF:
- A 1 Equipment of power grid and connection 50Hz.
- They include the stage of sectioning performed by means of a
thermal-magnet, as well as the stage of secondary protection made up of extra quick fuses for
- A 2 AC/DC converting device
- It is of the three-phase, entirely controlled type, realized with water cooled power thyristors, and
equipped with the necessary auxiliary devices to start and protect against excess voltage and/or
overcurrent, as well as to check cooling conditions.
- A 3 Intermediate circuit with direct current
- Made up of a filter with inductive input, obtained by means of a filter inductance of direct current
toghether with an equalization capacity of the intermediate D-C voltage.
- A 4 Inverter bridge
- It is of the mono-phase type entirely controlled, realized with "quick" power thyristors, water cooled
and equipped with the necessary auxiliary devices to start and protect against excess voltage and/or
overcurrent, as well as to check cooling conditions.
- A 5 Management electronics
- With remote control with computerised alarm diagnosticsv and visualisation of working parameters
on LCD display.
The converter is preset for the application of a two position pneumatic commutator to supply two
melting stations connected by coaxial cables up to a maximum distance of 30 m. Each melting
station has its own condensor box. If the commutator isn’t required, the converter will be supplied
with a condensor box to install close the melting station and connected to the converter by coaxial
cables up to a maximum distance of 30 m.
- A 6 Command system, signaling and measurement
- It includes the command devices and the pilot lamps of the converter working conditions, as well as
the selective signaling of failure conditions and the potentiometer regulating the voltage M F and,
therefore, the power delivered.
- A 7 Heat exchange group for the cooling of the converter
- The cooling cycle of the converter is "closed" with demineralized water, cooled by means of a water -
water plate exchanger with counter current exchange. The refrigeration group, including the above
mentioned exchanger, is modular and equipped with motor pump storage tank, as well as the
necessary command, regulation and control systems. Obviously it is necessary to supply the
exchanger with water coming from a water cooling plant at closed cycle (our model IRA), or from
one of your plants, but on conditions that the water caracteristics are like those above mentioned.
The above elements, which make up the converter, are placed in a locker built in sheet with strong welded
frames and equipped with front and back dustproof doors.
Degree of protection IP 54.
C) MELTING FURNACE
The furnace is made up of a strong iron frame with 18 mm thick stainless steel sidesto reduce losses
due to inductive phenomenae. The coil for induction heating is immersed in refractory cement. Both
crucible and coil are held in a fibre glass and resin casing of adequate thickness.
The crucible tilting system is hydraulic, by means of two stainless steel chains connected to a
hydraulic piston. In case of breakage of the chains, two hydraulic pistons will brake the
The tilting speed can be regulated.
The crucible spins around an imaginary axis passing through its edge.
The furnace is equipped with a propane gas burner to protect the metal and the crucible edge from
oxidation. The furnace is also equipped with a timer which automatically stops both propane gas
inflow and coil cooling pump 40-60 minutes after the generator has been stopped.
- Capacity of the crucible EX330 : 200 Kg of Ag
- Melting time : 30 minutes
- NOTE: This furnace can melt the equivalent of approx. 200 kg of silver every 30 minutes.
- coaxial cables 117/A 65,00
- Remote control panel 118/A €2.835,00
- 2ND CONDENSOR GROUP COND/2 €6.615,00
- TILTING GROUP FOR FIM/150 WITH EX181 RIB/C €45.000,00
Packing: € 700,00