The University of Texas System

Michael W Harville

William F Weldon

Robert W Carnes

Paul W Haase

The present invention provides a method and apparatus to control and verify weld-quality in a homopolar pulsed weld by measuring in-process parameters. Methods are disclosed for real-time weld-quality control in a weld-quality control system for homopolar pulsed welding, including measuring at least one in-process parameters that correlates to a resulting weld-quality of a weld. Further, methods are disclosed for post-process weld-quality verification for homopolar pulsed welding, including identifying at least one in-process parameter that may be used as a post-process weld-quality verification parameter and utilizing such a post-process weld-quality verification parameter to verify the weld-quality after a homopolar pulsed welding process.

Method and apparatus for real-time weld-quality control and post-process

The system of the present invention includes a homopolar generator, a hydraulic uniaxial press to hold the metal alloys to be welded, and electrical connections set at selected distances from the weld interface to provide a desired cooling rate for metal alloys being welded. A method is disclosed for determining a cooling rate for a metal alloy pipe in an electrical resistance welding process in a homopolar welding system following the resistive heating of a weld interface by discharging energy from a homopolar generator through electrodes attached to each of first and second pipes 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 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 by varying the electrode gap to provide a desired cooling rate following resistive heating of the weld interface and allowing the welded pipe segment to cool at the desired cooling rate.

Growing community of inventors

Austin, TX, United States of America

Michael W Harville