Fixed Tube Plate the most common and economical heat exchanger. In this system, both ends of the tube bundle are connected by welding or expanding permanently to the tubesheet which is integrated with the shell. This system is very effective for applications with high pressure and minimal risk of leakage. However, this tool has limitations in terms of maintenance. The inside of the shell is not easily cleaned mechanically and is difficult to reach. Therefore, this tool is best used for fluids that are clean or do not cause heavy scale on the sides of the shell.