Spiral Tube Heat Exchangers utilize one continuous spiral-wound tube or several parallel tubes in a circular pattern connected to headers on both ends.  This spiral coil is then installed in a shell where another fluid is circulated around the outside of the tube, transferring heat between the fluids. This construction allows for a ‘self-draining’ design when required. In general, the higher pressure fluid is located in the tube while the lower pressure fluid is in the shell.  Many designs can be rated for extremely high pressures (i.e. <1000 PSI, Tubeside Only). These heat exchangers offer unique advantageous for specific applications and are not necessarily the most economical option for every day heat transfer applications.