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Title: Semiconductor aspects of the oxyfuel cutting torch preheat flame; Part I: Measurements between torch and work
This two-part paper presents precise measurements of the ion currents passing between the torch and work piece of the preheat flame of an oxyfuel cutting torch as a means for replacing contemporary sensing suites. Part I shows that the current-voltage characteristic of the flame exhibits sharp discontinuities common to semi-conductors that we study in various configurations including preheat, pierce, cut, and loss-of-cut. Standoff measurements are made by applying a sinusoidal current signal between the torch and work piece while the resulting voltage amplitude is an indication of flame resistance. Uncertainties are estimated to range from 0.5mm to 1mm (.02in to .04in). Signals for ready-to-pierce and precursors for loss-of-cut are also produced due to the generation of secondary ions from chemical activity at the work piece.  more » « less
Award ID(s):
1900698
NSF-PAR ID:
10149600
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Proceedings of the ASME Manufacturing Science and Engineering Conference
Volume:
15
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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