SMS Elotherm of Germany has been awarded two orders for induction heating equipment by Ovako Tube and Ring AB in Hofors, Sweden. EloBar™ and EloTube™ machines by SMS Elotherm combine high energy efficiency with a comparatively small space requirement.
EloBar™ will be used at Ovako’s forging operations to heat steel bars at a production rate of up to 8,000 kg per hour. With an installed electrical power of 4,000 kW, bars of up to 130 mm diameter can be heated up to 1,220 °C.
SMS Elotherm supplies the bar handling system, the induction heater with a hot shear and an industrial robot for the transfer between hot shear and press.
Mr Torsten Schäfer sales representative at SMS Elotherm said that “EloBar™ belongs to our ForgeLine™ series which can be designed in a very flexible way. We have configured this energy-efficient system for Ovako precisely to the customer’s needs.”
The EloTube™ is part of a modernization program of Ovako. It will be placed in front of an existing Assel mill in a seamless tube plant. Hollow blooms coming directly from a rolling mill upstream will be reheated and equalized before entering the Assel mill.
Dr Guido Opezzo sales representative at SMS Elotherm said that “The temperature of the shell is increased to 1,100 °C a nd the better temperature homogeneity leads to enhanced product quality in the Assel mill operation. Also, the sizing forces can be reduced and the lifetime of the sizing rollers is extended due to less wear and tear.”
The induction system consists of six coils powered by state of the art converters with transistor technology totaling a rated power of 6,400 kW. The demand for floor space of this reheating unit is less than 7 m in length and 2.5 meters in width.
The process control is realized by a combination of a tube speed measurement system based on Laser Doppler technology and a bicolor pyrometer for temperature measurement. Mr Opezzo said that “The induced power is determined by the speed and the incoming temperature of the shell. Overheating of the material is prevented and the optimum temperature level for the following sizing mill operation is achieved.”
The EloBar™ and EloTube™ facilities will be commissioned in mid2013.
