Patent · US Expired

Apparatus and method for controlling powder deposition in a plasma spray process

US5047612A · kind A · utility

86Cited by
3References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 5, 1990
Grant dateSep 10, 1991
Priority date
Expiry dateFeb 5, 2010

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB05B7/226
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An apparatus and method for controlling the powder deposition and deposit pattern in a plasma spray process are provided in which an infrared imaging detector and associated processors are employed to provide an image of the temperature distribution of the deposit and to provide an identification of the impact point of the most recent powder deposit, and in which a cyclone separator or other device is used to modulate the flow rate of the carrier gas in which the powder is entrained at the point where the powder and gas are injected into a plasma plume, in order to move the impact point of the powder from the sensed location to a desired location. An injector tube is provided in a cross-flow injection system which may be sized to compensate for variations in the desired injection velocities of particles of different sizes, and the variations in the rate at which such particles are accelerated in the injection tube. A control computer is optionally provided to permit on-line control of the carrier gas flow rate by receiving the sensed image and comparing the information in the image to a reference pattern, and adjusting the carrier gas flow rate at the injector tube accordingly.

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