Annealing Steel Regulator Bases for a Fuel Injection System
Research Objective
To heat steel regulator bases for a fuel injection system to 1,950°F within 15 seconds for an annealing application
Parts & Materials Description
1 3/8” x 1/2” steel bases, temperature indicating paint
Temperature Required
1950°F
Induction Heating Equipment
3 kW power supply, remote heat station with one 0.25 microfarad capacitor and a specially-designed induction coil.
Operating Frequency
292 kHz
Heating Procedure
The steel part was positioned on a ceramic block. A special double-wound pancake coil was used to efficiently transfer RF power. Initial tests were conducted using temperature sensing paint to establish heating profiles and time-to-temperature. After the optimum time-to-temperature of 14 seconds was established, power was applied to the part until the temperature indicating paint melted. Tests were run in air without removing any oils on the surface, in air after cleaning the parts, and in an inert atmosphere after cleaning the parts.
Conclusion
The cleanest parts were produced in an inert atmosphere of 95% Nitrogen and 5% Hydrogen at 1950°F. within 14 seconds. The parts required no further processing before being used in the next operation.



