NDTnet 1998 Aug, Vol.3 No.8

Abstract

• Montreal protocol require operators of large cooling plants employing chloro-fluorocarbons (CFC) refrigeration to develop strategies for changing over to more environmentally friendly refrigerants and to contain CFC's currently in operation as effectively as possible.
• As contamination and wastage of the refrigerant is mainly due to heat exchanger tube, failures, an initiative was launched by Anglo American Corporation of SA Ltd's Mechanical Field Services to establish procedures to Non Destructively Test such tubes.

Content

• Background of ultra deep mining environment
• Selection of correct instruments to address this problem
• Initial test problems
• Development of test techniques
• Development of test procedures
• Development of tests specifications to comply with Anglo American Corporationrequirements
• Problems experienced with supply of raw tube material
• Condition monitoring of refrigeration plant heat exchanger tubes
Conclusion
The condition monitoring of refrigeration plant heat exchanger tubes has led to a substantial saving in running costs of the plant and reduction in down time. The introduction of the inspection system has also led to a great improvement of the quality of new tubes being supplied to the owners of the refrigeration plant.

Fig No 1

Illustration
Fig No 1 refers to a typical calibration curve

A =	0%	Internal wall loss
B =	10%	Internal wall loss
C =	71%	Internal wall loss
D =	100%	Through hole
E =	82%	External wall loss
F =	62%	External wall loss
G =	0%	External wall loss

Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00

Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:

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