when thicker metal in an alternating magnetic field, it will produce electric current .The metal current become stronger , temperature of metal became higher. The device is a kind of energy-saving equipment . it is installed in the combustion equipment before combusting, the high temperature (105 DEG -150 DEG) issued to reduce the fuel oil viscosity, promote full combustion . Hot Runner Coil Heater are widely used in hot-runner molds,blow molding,extrusion and hot nozzles.The hot runner heaters are annealed to acquire malleability for bending into any shape. Injection molding coil heaters with thermocouple are also available.