Most heat exchangers are designed with a certain amount of extra tube capacity to allow a percentage of tubes to be plugged during the life of the exchanger.

 

Two primary causes of tube failure, which often result in tubes being plugged or replaced, are erosion and corrosion. In fact heat exchangers are often completely re-tubed to repair tube failures which occur only at the tube ends.

 

The HydroSwage® Strain Control Sleeving System 43101 offers an economical method of prolonging the life of aging or failing heat exchanger tubes by installing sleeves (ferrules) to restore the lost tube material or as sacrificial barriers to the damaging elements which cause the tube loss.

 

Strain control is a two stage process which pre-expands a prepared metal sleeve into the damaged or failing section of the tube. The first stage expands the sleeve at a pre-calculated hydraulic pressure beyond the sleeve yield strength, but less than combined yield strength of the sleeve and parent tube.

 

The second stage of expansion is controlled by injecting (at a higher pressure) a pre-determined volume of water to control the radial expansion of the sleeve and parents tube to produce a constant interference fit between the sleeve and parent tube.