Function Structure
1. Cold rolled ribbed steel bar annealing production line is complete automatic control: two sets of medium frequency power supply accomplish annealing of ribbed steel bar online. Realize synchronization control of production line by several sets of inverters driving the mechanism.

2. There are totally two sets of heating power supply of cold rolled ribbed steel bar annealing production line, the power and frequency of which are designed to be: 500kW/8kHz，100kW/8kHz. The power supply adopts parallel IGBT induction heating power supply. It is just because of online heating that there’re strict requirements concerning working status and synchronization control of the power supply.

3. The parallel IGBT induction heating power supply adopts AC-DC-AC variable frequency power supply structure. The rectifier of the power supply adopts 3-phase thyristor rectifying or diode and IGBT chopper mode. The inverter adopts high voltage large power IGBT module and large power fast recovery diode to form inverter power unit. The resonant tank circuit adopts parallel resonance.

4. The whole unit of equipment is composed of two sets of induction heating equipment, water cooling system, console, automatic control system and mechanism system.

Technical Features

        Excellent heating power supply design
          1. Power supply cabinet and heating tank circuit adopt independent design with compact structure and small size which is convenient for site layout.
          2. The heating inductor is characterized by high heating efficiency of whole line and stable heating technics by optimization design.
          3. The power supply selects DC chopper mode to ensure the grid side power coefficient≥0.92 and a relative lower harmonic content.
          4. Adopt CPLD full digital control system, automatic fixed angle, high precision of phase-lock and wide scope of phase-lock. Perfect protection function, reliable working and low failure rate.
          5. High standard power supply electromagnetism compatibility design and closed cabinet design to meet the strict requirements at site.



      Perfect production and design
          1．Rapid increasing temperature and stable and precise temperature control to ensure a refinement of crystal inside rolled ribbed steel bar and greatly enhance physical property of steel bar, to meet high strength, high ductility and high anti-seismic mechanical property.
          2．Adopt all Chinese operation interface and matched with programmable controller, realizing precise control to rolling mill speed and temperature. The system adopts table look-up method to set and store different wire and speed which is very convenient.
          3．Full line fault alarm analysis system, which can be displayed on heating operation interface, can find the source of trouble in the first time (any abnormal operation of the line can be displayed on the interface).
          4．Adopt infrared thermometer to measure the temperature of wire exit, which is convenient to adjust power and temperature.
          5．Adopt special material for barrel type conduct at entrance of capacitor cabinet, select stainless steel guide wheel as the shape of Chinese character “品”between the inductor, to make location of center line for steel bar.

Main Technical Parameter

Model	AC input	Power coefficient	Rated DC voltage	Rated DC current	Frequency scope	Heating mode
GZP-500/8 + GZP-100/8	3AC380V 50/60Hz	0.95	500V	1000A	6－8kHz	Annealing
	3AC380V 50/60Hz	0.95	500V	200A	6~8 kHz	heat preservation
GZP-600/8	3AC380V 50/60Hz	0.95	500V	1200A	6~8 kHz	Annealing heat preservation

* Heating power and frequency can be customized as per user’s technics requirements.



Operation parameter（ annealing temperature 600℃）

steel bar specification（mm）	φ6	φ7	φ8	φ9	φ10	φ11	φ12
heating speed（m/min）	180	180	180	160	130	100	90
output   per hour （T）	2.398	3.263	4.262	4.795	4.810	4.476	4.795
Power consumption per ton（kwh）	101	102	103	106	106	110	110

Can be customized according to user’s grid; General design, can be designed as per user’s technics; For more information, please contact EECTECH