A Double Pipe Heat Exchanger consists of one pipe inside another, allowing two fluids to flow separately—one through the inner pipe and the other through the annular space. Heat is exchanged between the fluids through the pipe wall. It is simple, compact, and ideal for high-pressure or small-scale industrial applications. https://www.heatexchanger.co.in/Heat-Exchanger/Double-Pipe-Heat-Exchanger/