Patent ID: 8263915

Claim:
An impeder for controlling the magnetic field path in a workpiece in an electric induction welding process, the impeder comprising: a magnetic material having at least one entry passage formed centrally therethrough for an entry flow of a cooling medium at a first end of the magnetic material; and a high temperature enclosure surrounding the magnetic material, the exterior of the magnetic material spaced apart from the interior wall of the high temperature enclosure to form at least one exit passage for exit flow of the cooling medium at the first end of the magnetic material, the at least one exit passage in communication with the at least one entry passage, the high temperature enclosure having at least one inlet port connected to the at least one entry passage for injecting the cooling medium into the at least one entry passage and at least one outlet port connected to the at least one exit passage for discharging the cooling medium from the at least one exit passage.