Method for producing heat pipe units

A method for producing a heat pipe unit having at least one heat pipe carried in a plate-like cross-structure, comprising:

• placing a heat pipe in a molding box;
• holding said heat pipe in an upright position in said molding box;
• feeding sand into said molding box to bury said heat pipe up to a level where said plate-like cross-structure is to be provided, while vibrating said molding box to compact the sand and level the surface thereof;
• pouring a molding material on the levelled surface of said sand to a predetermined thickness;
• solidifying said molding material to form a platelike cross-structure on said heat pipe integrally therewith;
• discharging said sand out of said molding box;
• and
• removing the thus-formed heat pipe unit from said molding box.