Conveying through furnaces

A conveyor unit system for moving products in a conveying direction through a furnace, the unit system comprising:

• a plurality of first elongated beams extending along the conveying direction and arranged substantially parallel to each other, wherein
• the first beams are slidably mounted on rollers and are constrained to be only displaceable in a back-and-forth reciprocating motion along the conveying direction between an upstream position and a downstream position,
• a plurality of second elongated beams extending along the conveying direction and arranged interleaved with the first beams, wherein
• the second beams are constrained to be only displaceable in an up-and-down reciprocating motion between a lower vertical position and an upper vertical position along a vertical direction that is defined in a plane substantially perpendicular to a plane of the conveying direction,
• wherein an upper working surface of the first beams that in use supports the products is positioned along the vertical direction, between the lower vertical position and the upper vertical position,
• wherein the rollers are defined by outer protrusions circumferentially provided on one or more rotatable shafts, the shafts being arranged substantially transversally to the first beams, and
• wherein the first beams comprise an inverted U-shaped cross-section or an H-shaped cross-section in which the outer protrusions of the rollers are housed so as to protect the outer protrusions of the rollers from contaminants falling from the products.