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Title: Method and apparatus for real time weld monitoring

Abstract

An improved method and apparatus are provided for real time weld monitoring. An infrared signature emitted by a hot weld surface during welding is detected and this signature is compared with an infrared signature emitted by the weld surface during steady state conditions. The result is correlated with weld penetration. The signal processing is simpler than for either UV or acoustic techniques. Changes in the weld process, such as changes in the transmitted laser beam power, quality or positioning of the laser beam, change the resulting weld surface features and temperature of the weld surface, thereby resulting in a change in the direction and amount of infrared emissions. This change in emissions is monitored by an IR sensitive detecting apparatus that is sensitive to the appropriate wavelength region for the hot weld surface.

Inventors:
 [1];  [2]
  1. Lemont, IL
  2. Bolingbrook, IL
Issue Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
OSTI Identifier:
871168
Patent Number(s):
5674415
Assignee:
University of Chicago (Chicago, IL)
Patent Classifications (CPCs):
B - PERFORMING OPERATIONS B23 - MACHINE TOOLS B23K - SOLDERING OR UNSOLDERING
DOE Contract Number:  
W-31109-ENG-38
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
method; apparatus; time; weld; monitoring; improved; provided; infrared; signature; emitted; hot; surface; welding; detected; compared; steady; conditions; result; correlated; penetration; signal; processing; simpler; acoustic; techniques; changes; process; transmitted; laser; beam; power; quality; positioning; change; resulting; features; temperature; direction; amount; emissions; monitored; sensitive; detecting; appropriate; wavelength; region; wavelength region; surface feature; surface features; infrared emission; signal processing; improved method; laser beam; beam power; resulting weld; weld penetration; appropriate wavelength; signal process; detecting apparatus; weld monitoring; time weld; weld monitor; /219/

Citation Formats

Leong, Keng H, and Hunter, Boyd V. Method and apparatus for real time weld monitoring. United States: N. p., 1997. Web.
Leong, Keng H, & Hunter, Boyd V. Method and apparatus for real time weld monitoring. United States.
Leong, Keng H, and Hunter, Boyd V. Wed . "Method and apparatus for real time weld monitoring". United States. https://www.osti.gov/servlets/purl/871168.
@article{osti_871168,
title = {Method and apparatus for real time weld monitoring},
author = {Leong, Keng H and Hunter, Boyd V},
abstractNote = {An improved method and apparatus are provided for real time weld monitoring. An infrared signature emitted by a hot weld surface during welding is detected and this signature is compared with an infrared signature emitted by the weld surface during steady state conditions. The result is correlated with weld penetration. The signal processing is simpler than for either UV or acoustic techniques. Changes in the weld process, such as changes in the transmitted laser beam power, quality or positioning of the laser beam, change the resulting weld surface features and temperature of the weld surface, thereby resulting in a change in the direction and amount of infrared emissions. This change in emissions is monitored by an IR sensitive detecting apparatus that is sensitive to the appropriate wavelength region for the hot weld surface.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1997},
month = {1}
}

Patent:

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Works referenced in this record:

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