Patent ID: 7669644

Claim:
A heat exchanger, comprising: a casing having at least one part of a path for passage of a first fluid within said casing, said path comprising at least one first pipe wound in a first spiral, the casing receiving a second fluid that is in a heat-exchange relationship with the first fluid; wherein said at least one first pipe is shaped to form a plurality of spacer portions on at least a first portion of said at least one first pipe that includes a first plurality of turns; wherein at least one turn of said plurality of turns comprises turn spacer portions, said turn spacer portions contacting at least one adjacent turn of said plurality of turns, such that an interstice is defined between said at least one turn and said at least one adjacent turn; wherein each turn of said plurality of turns comprises consecutive turn spacer portions spaced apart from each other in a length direction of each turn; and wherein each turn spacer portion of said turn spacer portions contacts said at least one adjacent turn at a first surface region of said at least one adjacent turn, said first surface region located between two consecutive adjacent turn spacer portions of said at least one adjacent turn, or each adjacent turn spacer portion of said at least one adjacent turn contacts said at least one turn at a second surface region of said at least one turn, said second region located between two consecutive turn spacer portions of said turn spacer portions of said at least one turn.