Standard Weld-Wire Composition by Eddy-Current Testing

This project will provide a low cost method of continuously assuring that the weld filler wire required by qualified Welding Procedure Specifications has been used. The method will be based on continuous eddy current testing. The weldments will have the required resistance to welding and service environments. The lower cost will be due to eliminating hand labor to administer the present safeguard against mixed weld wire. The eddy current alloy sorting test will adapt the mature technology of defect inspection for long life, high pressure high temperature tubing. The pickup coil will be designed for sensitivity adequate to detect steady state and transient changes of composition and microstructure due to wire grade change. The parameters of possible and actual grade changes will be determined by a test of several stainless steel rod end-to-end welds. Technical problems avoided would include possible hot cracking during welding and excessive corrosion in service. Administrative burdens to low overhead technically capable welding shops, incentives to decline to bid, would also be removed. Cost, delivery and availability problems could be eliminated.