Suction heaters present an optimal solution for heating tank contents efficiently. These heaters are specifically designed to be bolted directly into a storage tank via a manway or large flange. The design comprises a tube bundle with a partial shell, which is inserted into the tank. The heating medium, often steam, is circulated through these tubes, thereby transferring heat to the tank's contents as they are pumped out. This process is instrumental in reducing the viscosity and improving the flow properties of the tank's contents, ultimately decreasing the power required for pumping. Suction heaters are predominantly used in oil tank heating applications and are constructed from carbon steel, though they can be made from various materials to meet different specifications. They are built to comply with Section VIII, Div 1, API standards, and any specific customer requirements.