Patent ID: 11933547
Assignee: DANFOSS A/S
Field: Thermal processes and apparatus (Mechanical engineering)
Classification: CPC F | IPC F

Claim 10:
11. A plate heat exchanger comprising a stack of plate elements each plate element being of a double wall construction comprising a first heat transfer plate and a second heat transfer plate each comprising a central heat exchanging portion provided with surface patterns adapted for a surface pattern of first heat transfer plate of one plate element to contact a surface pattern of a second heat transfer plate of a neighbouring plate element forming a first flow path for a first fluid at the one side and second flow path for a second fluid at the second side of a plate element, where the plate elements are formed with openings in opening areas, wherein a first heat transfer plate in an opening area is formed with a closed projection projecting in a first direction, and in the same opening area is formed with an open projection formed on a second direction being opposite to the first direction, such that the closed and open projections together defines a first leak cavity, where the open projection is adapted to allow fluid to pass between the respective opening and the respective flow path when connected to open projections of a neighbouring plate element, where the closed projection is adapted to close for fluid and seal the respective opening from the respective flow path, and wherein a plural of open projections are positioned around the full circumference of the respective opening, and where a single closed projection circumferences the respective opening.