Abstract: A diaphragm for use in a fluid storage tank in which the fluid storage tank comprises first and second shell portions defining an interior tank space, wherein the diaphragm is configured to be secured within the interior tank space between the first and second shell portions, to define a fluid storage reservoir between the diaphragm and one of the shell portions. The diaphragm comprises a body of deformable material having a part-spherical portion defining a central longitudinal axis. A thickness of the diaphragm varies between different regions of the diaphragm. The thickness of the diaphragm is asymmetric about the longitudinal axis. Also provided is a fluid storage tank including such a diaphragm.

Abstract: A diaphragm for use in a fluid storage tank in which the fluid storage tank comprises first and second shell portions defining an interior tank space, wherein the diaphragm is configured to be secured within the interior tank space between the first and second shell portions, to define a fluid storage reservoir between the diaphragm and one of the shell portions. The diaphragm comprises a body of deformable material having a part-spherical portion defining a central longitudinal axis. A thickness of the diaphragm varies between different regions of the diaphragm. The thickness of the diaphragm is asymmetric about the longitudinal axis. Also provided is a fluid storage tank including such a diaphragm.