A shell & tube type cooler tubes are leaking, what is the procedure to rectify the leaks?

1. A holed tube should be plugged from both the sides. The plugs can be of cork, wood, rubber, brass, or copper as supplied by the manufacturer. Care should be taken when plugging with the metal plugs, not to damage the tube plate.
2. If the leaks are from the gaps between the tube plate and the tubes, slight flaring of the tube may help preventing the leaks however this flaring, if excessive will damage the tube plate and also the tube itself.
3. Alternative methods are available by carrying out surface preparation and applying metal repair putty, like Devcon’s brush able ceramic repair putty.

FIG.: Different types of plugs

Note: In the above process, if the plugging of the tubes is about 10% the tubes have to be renewed.