HEAT-AFFECTED ZONE CRACKING IN WELDED TRANSMISSION POLES

Tubular transmission line structures are used by numerous utilities for power distribution, and many of these structures are hot-dip galvanized to provide adequate atmospheric corrosion protection. Recent investigations by both utilities and manufacturers have disclosed a cracking problem, which is associated with the tubular shaft-to-base plate weldment. An investigative program was initiated with the intent to define more clearly when these cracks occur and, if possible, by what mechanism. Typical production weldments were monitored during the fabrication and galvanizing stage using ultrasonic examination techniques. Temperature gradients were obtained during welding and galvanizing by attachment of thermocouples in selected areas. The results of the four investigations performed disclosed some cracking in two of the tests, and no cracking in the other two tests. Metallographic techniques were used to document results of three of the four tests. A correlation between ultrasonic inspection results and the flaws discovered by sectioning is presented as well as the results of the metallographic investigation.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00255327
• Corporate Authors:

  American Society for Nondestructive Testing

  914 Chicago Avenue
  Evanston, IL  United States  60202
• Authors:
  • Herrschaft, D C
  • Watson, P D
• Publication Date: 1975-6

Media Info

• Features: Figures; Photos;
• Pagination: p. 121-127
• Serial:
  • Materials Evaluation
  • Volume: 33
  • Issue Number: 6
  • Publisher: American Society for Nondestructive Testing
  • ISSN: 0025-5327

Subject/Index Terms

• TRT Terms: Corrosion resistance; Fracture mechanics; Galvanizing; Metallography; Transmission lines; Tubular structures; Ultrasonic tests; Utility poles; Weldments
• Old TRIS Terms: Hot dip galvanizing
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00098435
• Record Type: Publication
• Files: TRIS
• Created Date: Sep 30 1975 12:00AM