Patent · US Expired

Electrode for plasma arc torch having channels to extend service life

US5451739A · kind A · utility

40Cited by
7References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 19, 1994
Grant dateSep 19, 1995
Priority date
Expiry dateAug 19, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05H1/3468
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An electrode and method of operating a plasma arc torch is provided which extends the useful service life of the torch. The electrode includes an elongate tubular holder defining a longitudinal axis and having a discharge end. An endwall closes the discharge end and includes an emissive insert. In one embodiment, the endwall also includes an annular sleeve which separates the insert from physical contact with the holder. Channels formed in the discharge end of the electrode direct a portion of a swirling vortex of gas across the surface of the endwall. The swirling vortex of gas removes products of erosion of the insert and adjacent portion of the sleeve such that the likelihood that arcing will transfer from the insert to the sleeve and/or holder is reduced, and the useful service life of the nozzle-electrode pair is thereby extended.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.