Patent Number: 043953808
Section: claims

1. A method for remotely testing the fluid flow condition in a tubular extension of a pipe, the interior of said extension communicating with the interior of said pipe, said method comprising: supplying a fluid under a pressure above atmospheric pressure and at a temperature at least 5.degree. F. above the temperature of the ambient to the interior of said pipe, whereby said fluid flows out of said extension if it is unblocked, and continuing the supply of said fluid to the interior of said pipe for a time sufficient to raise the temperature of said pipe and an unblocked extension to a temperature at least one-half degree F. above the ambient temperature and above the temperature thereof prior to the supply of said fluid thereto; and scanning said pipe and said extension with an infrared detector from a point remote from said pipe and said extension to obtain a thermogram of the pipe and the extension, an unblocked extension appearing as an image of the extension and a blocked extension not providing a significant image, whereby the fluid-flow condition of the extension is indicated by the image of the extension on the thermogram.  supplying air under a pressure above atmospheric pressure to said nozzles by way of said header, said air having a temperature such that the temperature of the air passing through the nozzles is in the range from 5.degree. F. above the temperature of the ambient for the nozzles to 200.degree. F., and continuing the supply of said air to said nozzles for a time sufficient to raise the temperature of an unblocked nozzle to a temperature at least one-half degree F. above the ambient temperature and above the temperature thereof prior to the supply of air thereto; and  scanning said header and said nozzles while said air is supplied thereto with an infrared camera located remotely from the header and having a thermogram display to obtain a thermogram of the header and each nozzle, an unblocked nozzle appearing as an image of the nozzle and a blocked nozzle not providing a significant image, whereby the fluid-flow condition of the nozzle is indicated by the image of the extension on the thermogram. 2. A method as set forth in claim 1 wherein said fluid is air. 3. A method as set forth in claim 2 wherein the temperature of the fluid supplied to said pipe is selected to provide a temperature of the fluid at said extension which is at least 100.degree. F. 4. A method as set forth in claim 1 wherein said pipe is ring shaped and has a plurality of said extensions spaced from each other thereon in the form of spray nozzles, and wherein said method further comprising moving said infrared detector about the axis of the ring-shaped pipe as said pipe and the extensions are scanned. 5. A method for remotely testing the fluid flow condition of a plurality of metal spray nozzles mounted in spaced relation on a ring-shaped, metal header within the containment building for a nuclear reactor, said nozzles having fluid communication with said header and extending outwardly from said header for delivering fluid supplied to the header to the interior of said building, said method comprising: 6. A method as set forth in claim 5 wherein the scanning of said header and said nozzles includes moving said camera around the ring axis of said ring-shaped header.