DETERMINING, CONTROLLING ELECTRICAL RESISTANCE

摘要

The system of the present invention includes a homopolar generator, a hydraulic uniaxial press to hold the metal alloys to be welded (102), and electrical connections (101) set at selected distances from the weld interface (103) to provide a desired cooling rate for metal alloys (102) being welded. A method is disclosed for determining a cooling rate for a metal alloy pipe (102) in an electrical resistance welding process in a homopolar welding system following the resistive heating of a weld interface (103) by discharging energy from a homopolar generator through electrodes (101) attached to each of first and second pipes (102) to form a welded pipe segment. The temperature of the welded pipe segment is measured at periodic time intervals to determine a cooling rate for the welded pipe segment. A desired range for the cooling rate may be determined by adjusting the electrode gap (105) for repeated samples and analyzing the resulting metallurgical properties for each sample. In a further aspect, a method is disclosed for controlling the cooling rate of metal alloy pipe (102) by varying the electrode gap (105) to provide a desired cooling rate following resistive heating of the weld interface (103) and allowing the welded pipe (102) segment to cool at the desired cooling rate.