Electrical flange immersion heaters are designed for heating or temperature maintening of liquids, gas or mixture in static or circulation conditions.
The design is based on customer process conditions: fluid to heat (type and properties), in/out temperature, pressure, heat exchange conditions (stagnant or flowing), and environment conditions (ATEX or not, onshore or offshore, etc.).
Flange immersion heaters can be straight or L-shaped. http://www.etdzheater.com