Leak detection in heat exchanger tubes and their tube sheet connections
AssigneeStal-Laval Apparat AB
InventorsKarl G. Dahmen, Roger Eriksson
Life of this patent
Estimating the term…
Abstract
To test a shutdown steam condenser for tube leakage, the pressure in the water boxes is reduced below atmospheric pressure while the steam casing is open to atmospheric pressure, and leakage of air into the boxes is used as an indication of the tube leakage. The leakage is preferably indicated with a soap bubble test by a workman inside the box. Although the entrance manholes to the water box are substantially sealed during testing, for safety protection one can be sealed with a U-tube water seal so that it will be broken automatically by an excessive underpressure.
Claims4
A method for detecting leaks in a shutdown steam condenser and the like having a bundle of tubes with their ends connected in tube sheets having outsides enclosed by water boxes and the tubes and insides of the tube sheets enclosed by a steam casing;
- said method comprising giving the casing access to the ambient air, reducing the air pressure in the water boxes to below that of the ambient air, and from within at least one of the water boxes examining the tube ends and their connections in the tube sheet for leakage of the air from the casing into the water boxes, the examining being effected by applying to the tube ends and their connections in the tube sheet a fluid that forms air bubbles in the event the air in the casing leaks through either the tubes or their connections in the tube sheet and thereby into that one of the water boxes.
Dependencies are inferred from the claim text.