| abstract |
The diaphragm-type expansion vessel is intended for a central heating system, the diaphragm forming a chamber accommodating the expansion water, so as to equalise pressure. The diaphragm (9) is a metal foil, secured by a seal (17) to the inside of the vessel (2). The vessel preferably comprises a cylindrical central portion (1) and top and bottom domes (3, 4) the diaphragm being secured to the bottom dome. The diaphragm may be in the form of a cylindrical bellows with a rigid cowl (11) of cup shape curved towards the cylinder outer surface at one end, and a foot (16) at the other one, by which it is secured to the vessel. |