Patent · US Expired

Method and camera system for the inspection of boiler tubes

US4699485A · kind A · utility

3Cited by
7References
13Claims
0Family size

Inventors

Key dates

Filing dateMar 29, 1985
Grant dateOct 13, 1987
Priority date
Expiry dateMar 29, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B37/005
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In a fire tube boiler, combustion takes place in elongated boiler tubes, which are subject to corrosion, wear, deposition build-up and color changes. A cylindrical camera body, round in cross-section, is inserted into a still-hot boiler tube. The camera body is cooled by cooling fluid and is pushed along the tube using extension rods. A motion picture film strip, preferably color instant film within a cassette, is advanced by remote control, by the operator, to expose a sequence of film frames on the cassette's film plane, as the camera body is progressed within the tube. The tube is dark so that a camera shutter is not used. Instead, tiny light sources, such as incandescent bulbs and/or a swingable mirror, are used to select the exposure time of the film. A fixed-focus and fixed-distance lens system focuses the images from the tube's inner wall on the film plane.

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