Heat exchangers pipe in pipe single-flow non-separable TTON

Single-threaded non-separable pipe-to-tube heat exchangers are poorly adapted to work with complex media, they are used in cases where the medium that circulates in the annular space does not contaminate the outer surface of the heat-exchange pipes.
TTON heat exchangers with welded doubles are used at technological stages where the medium passing through the pipe space does not deposit on the inner surface of the pipes.
TTON heat exchangers with removable twins are used when the media involved in the heat exchange process produce deposits on the inner surface of the pipes, which requires regular mechanical cleaning.