Flexible solution for stress relieving annealing of shell and tube heat exchangers

Smit Industrial Heat Treatment is well-known for not shying away from challenges, and to always explore flexible solutions for even the most complex issues. The success of the heat treatment specialist is demonstrated by this footage of the stress relieving annealing of a shell and tube heat exchanger.

Enlarging the furnace

To prevent the tubes and tube-sheet of the heat exchanger from deforming during the heating process, the exchanger had to be suspended during treatment. In order to achieve this, it was necessary to temporarily increase the height of the oven, and moreover, to ‘go down into the ground’ so that the total length of the heat exchanger would fit vertically inside the furnace.

Air quench

Over approximately 24 hours, the project was heated up at 40 degrees Celsius per hour to about 1,100 degrees Celsius. Using air quench – forced cooling with the use of air – the exchanger was then rapidly cooled down. Fast cooling is required to retain the corrosion resistant properties of the material.