A support for a bundle of parallel tubes, comprising at least two spaced
apart transverse support plates, wherein each plate is provided with a
plurality of openings of substantially rhombical or substantially
frustro-rhombical shape, each of which openings having a maximum of two
mirror symmetry axes including a characteristic mirror symmetry axis, the
openings being large enough to accommodate at least two tubes, wherein
openings in different support plates are arranged to form support
passages for parallel tubes so that support passages extending through
the same opening in one support plate extend through different openings
in another support plate, and wherein the characteristic mirror symmetry
axes of at least two openings belonging to the same support passage are
arranged to extend in different directions.