Patent ID: 8109326

Claim:
A heat transfer plate intended to constitute, together with other heat transfer plates, a plate stack with permanently connected plates for a heat exchanger, which heat transfer plate comprises a first long side and an opposite second long side, a first short side and an opposite second short side, a heat transfer surface exhibiting a pattern of ridges and valleys, first and second port regions, the first port region being situated in a first corner portion formed at the meeting between the first long side and the first short side, the second port region being situated in a second corner portion formed at the meeting between the second long side and the first short side, and the first port region being connected to a number of ridges and valleys, which ridges and valleys have in principle an extent from the first port region diagonally towards the second long side, wherein a number of contact points are situated on the ridges in direct proximity to the first port region, which contact points are so positioned that at least one contact point adjoins two contact points, the contact points being in principle at the same radial distance from the center of the first port region wherein a first ridge and a second ridge form between them a second valley, the first ridge extending between the two port regions and the valley extending from one port region at one long side to the opposite second long side; and wherein the second ridge is connected to a third ridge by a first connection whereby a third valley is formed between the second and third ridges, which third valley has an open end and a closed end.