Porthole gasket for a plate heat exchanger, a plate package and a plate heat exchanger with such a porthole gasket

Abstract

A porthole gasket is configured to seal a circumferential region around two overlapping portholes in two adjacent heat exchanger plates of a plate heat exchanger, so as to define a passage for a fluid into or out of the plate heat exchanger. The porthole gasket has a ring-shaped portion to be compressed between the two adjacent heat exchanger plates while surrounding the overlapping portholes. The porthole gasket further comprises a plurality of projections that protrude from an outer perimeter of the ring-shaped portion and are configured to be compressed between the two adjacent heat exchanger plates so as to support the ring-shaped portion against pressure exerted by the fluid. A plate package for a plate heat exchanger is configured to include the two adjacent heat exchanger plates and the porthole gasket.

1 . A porthole gasket for installation between two adjacent heat exchanger plates of a plate heat exchanger, the porthole gasket being configured to seal a circumferential region around two overlapping portholes, each of which being formed in a respective one of the two adjacent heat exchanger plates, so as to define a passage for a fluid into or out of the plate heat exchanger, wherein the porthole gasket comprises a ring-shaped portion configured to be compressed between the two adjacent heat exchanger plates while surrounding the overlapping portholes, the porthole gasket further comprising a plurality of projections that protrude from an outer perimeter of the ring-shaped portion and are configured to be compressed between the two adjacent heat exchanger plates so as to support the ring-shaped portion against pressure exerted by the fluid. 
     
     
         2 . The porthole gasket of  claim 1 , wherein at least one of the projections comprises a friction-enhancing surface pattern that defines a patterned first surface portion For engaging a first one of the two adjacent heat exchanger plates when the projections are compressed between the two adjacent heat exchanger plates. 
     
     
         3 . The porthole gasket of  claim 2 , wherein the surface pattern defines a patterned second surface portion for engaging a second one of the two adjacent heat exchanger plates when the projections are compressed between the two adjacent heat exchanger plates, the first and second surface portions being arranged on opposite sides of said at least one of the projections. 
     
     
         4 . The porthole gasket of  claim 2 , wherein the surface pattern comprises a plurality of spaced-apart pattern structures, as seen parallel to a normal direction (N) of the patterned first surface portion. 
     
     
         5 . The porthole gasket of  claim 4 , wherein the pattern structures comprise protrusions protruding, parallel to the normal direction of the patterned first surface portion, from a bulk portion of said at least one of the projections, to define the patterned first surface portion. 
     
     
         6 . The porthole gasket of  claim 4 , wherein the pattern structures comprise elongated ribs. 
     
     
         7 . The porthole gasket of  claim 4 , wherein said at least one of the projections is elongated and extend in a longitudinal direction away from the outer perimeter of the ring-shaped portion, and wherein at least part of the pattern structures extend essentially transverse to the longitudinal direction. 
     
     
         8 . The porthole gasket of  claim 1 , wherein at least a subset of the projections are elongated and extend in a longitudinal direction away from the outer perimeter of the ring-shaped portion. 
     
     
         9 . The porthole gasket of  claim 8 , wherein the longitudinal direction is non-perpendicular to the outer perimeter of the ring-shaped portion, for at least one of the projections. 
     
     
         10 . The porthole gasket of  claim 1 , which further comprises an attachment member which protrudes from an inner perimeter of the ring-shaped portion and is arranged to engage with an edge portion of one of the overlapping portholes. 
     
     
         11 . A plate heat exchanger, comprising a porthole gasket according to  claim 1 . 
     
     
         12 . A plate package for a plate heat exchanger, comprising two adjacent heat exchanger plates and the porthole gasket according to  claim 1  compressed between the two adjacent heat exchanger plates, each of the two adjacent heat exchanger plates being formed with a porthole, the portholes of the two adjacent heat exchanger plates being overlapping, and the porthole gasket surrounding the portholes. 
     
     
         13 . The plate package of  claim 12 , wherein each of the projections is compressed between a respective pair of opposite engagement surfaces on the two adjacent heat exchanger plates, and wherein each of the projections has a thickness, before compression, which exceeds a distance between the respective pair of opposite engagement surfaces by approximately 5-20%. 
     
     
         14 . The plate package of  claim 12 , wherein the ring-shaped portion is located in a ring groove formed in at least one of the two adjacent heat exchanger plates, and wherein at least a subset of the projections are located in channels that are defined by the two adjacent heat exchanger plates to extend away from the ring groove. 
     
     
         15 . The plate package of  claim 14 , wherein one or more of the projections is fitted in a respective one of the channels that has a non-linear extent away from the ring groove, wherein each of said one or more of the projections has an extent that conforms to the non-linear extent of the respective one of the channels.