Wärmetauscher und Wärmetauscherrohr dafür

A fluid pipe (14) for fluid flow between a pair of manifolds of a heat exchanger and which is formed from a single piece of sheet metallic material having a cladding on at least one surface, the fluid pipe having a first side wall (40) having a first portion (46) and a second portion (48); a second side wall (42) extending substantially parallel to and spaced from the first side wall; a pair of end walls (44) connecting the first and second side walls; first, second and third internal walls (50-54) positioned internally of the first and second side walls and the end walls, the first, second and third internal walls being spaced apart and spaced from the end walls, and extending between the first and second side walls, the first internal wall being of double the thickness of the sheet and being positioned intermediate the second and third internal walls; a first planar side portion (56) connecting the first and second internal walls and contacting a first planar part (58) of the internal surface of the second side wall; a second planar side portion (60) connecting the first and third internal walls and contacting a second planar part (62) of the internal surface of the second side wall; a third planar side portion (64) connected to the second internal wall and contacting a planar part (66) of the internal surface of the first portion of the first side wall; and a fourth planar side portion (68) connected to the third internal wall and contacting a planar part (70) of the internal surface of the second portion of the first side wall. The invention also includes a heat exchanger having a number of such fluid pipes. The fluid pipes of the present invention have increased strength over known arrangements.