The Thermal Transfer Products UC/UCV series is a U-tube heat exchanger that is resistant to temperature fluctuation. The product supports independent expansion and contract of the shell and tube bundle, which reduces the thermal stress caused by a temperature difference, ensuring high adaptability to the application scenarios in which a great temperature difference occurs. In this series, various materials are provided to meet different requirements for cooling water in the oil or steam application scenarios. Moreover, the U-shaped tube bundle can be removed for maintenance, cleaning and replacement, without affecting the equipment installation and shell-side connection, thereby reducing the maintenance cost and complexity.