An accumulator is provided, which is aimed at stabilization in mounting state of a damping member while diminishing the impact on a metal bellows. In an accumulator (100), a damping member (190) formed slidably at the inner circumferential surface of a pressure vessel (110) and suppressing the oscillation of a metal bellows (130) while keeping a gap between the metal bellows (130) and the inner circumferential surface of the pressure vessel (110) is mounted at at least one site of a plurality of annular valley parts of the metal bellows(130) including a plurality of annular crest parts and the plurality of annular valley parts alternately formed therein. In the damping member (190), a radially inward tip is fitted with the valley part, and a radially outward tip is longer than the crest part of the metal bellows radially and outwardly.

An accumulator is provided, which is aimed at stabilization in mounting state of a damping member while diminishing the impact on a metal bellows. In an accumulator (100), a damping member (190) formed slidably at the inner circumferential surface of a pressure vessel (110) and suppressing the oscillation of a metal bellows (130) while keeping a gap between the metal bellows (130) and the inner circumferential surface of the pressure vessel (110) is mounted at at least one site of a plurality of annular valley parts of the metal bellows(130) including a plurality of annular crest parts and the plurality of annular valley parts alternately formed therein. In the damping member (190), a radially inward tip is fitted with the valley part, and a radially outward tip is longer than the crest part of the metal bellows radially and outwardly.

An expansion tank with an improved diaphragm seal includes a seal for the joint between the flexible diaphragm and either an optional. non-flexible diaphragm or the tank wall, the providing of a seal support that prevents collapse, delamination, or tearing of the 5 tank shell wall. The tank shell may be formed of two substantially hemispherical domes joined together, either directly or at the two ends of a substantially cylindrical section. One of the segments forming the shell of the expansion tank, further comprises an extension lip, extending inwardly of the tank and around the entire circumference of the inner surface of the shell wall, located substantially near the junction of two of the sections 10 forming the tank. This extension lip may be made from the same material as the tank wall, or may be part of a separate circumferential connector interconnecting two of the sections of the tank wall.

An expansion tank with an improved diaphragm seal includes a seal for the joint between the flexible diaphragm and either an optional. non-flexible diaphragm or the tank wall, the providing of a seal support that prevents collapse, delamination, or tearing of the 5 tank shell wall. The tank shell may be formed of two substantially hemispherical domes joined together, either directly or at the two ends of a substantially cylindrical section. One of the segments forming the shell of the expansion tank, further comprises an extension lip, extending inwardly of the tank and around the entire circumference of the inner surface of the shell wall, located substantially near the junction of two of the sections 10 forming the tank. This extension lip may be made from the same material as the tank wall, or may be part of a separate circumferential connector interconnecting two of the sections of the tank wall.

An accumulator capable of suppressing collision of a metal bellows with a pressure vessel. A partition unit 300 includes: a tubular metal bellows 310, one end of which is side fixed to a pressure vessel 200 and which expands and contracts according to pressure in a fluid chamber and pressure in a gas chamber; and a bellows cap 320 which is fixed to another end side of the metal bellows 310, the partition unit 300 further including: a seal member 330 which is provided between the bellows cap 320 and a port 221 and seals a working fluid on the side of the fluid chamber via the metal bellows 310 when the metal bellows 310 contracts; and a sliding unit 350 which is fixed to the bellows cap 320 and slides in an expansion/contraction direction of the metal bellows 310 relative to a stay 400.

The disclosure relates to an hydraulic accumulator, in particular a diaphragm accumulator, having an accumulator housing and a separating element disposed therein, which separates two media spaces from each other, wherein a weld seam is formed by a laser or electron beam welding process without any filler materials, in that at least a part of the wall parts delimiting the transition point are melted to form the weld seam, which closes off the transition point towards the surroundings, in a manner that is free of protrusions with respect to an outer circumferential surface of a connection element.

The disclosure relates to an hydraulic accumulator, in particular a diaphragm accumulator, having an accumulator housing and a separating element disposed therein, which separates two media spaces from each other, wherein a weld seam is formed by a laser or electron beam welding process without any filler materials, in that at least a part of the wall parts delimiting the transition point are melted to form the weld seam, which closes off the transition point towards the surroundings, in a manner that is free of protrusions with respect to an outer circumferential surface of a connection element.

Disclosed is an expansion tank having an internal cavity separated by a flexible diaphragm to form an upper pressurized gas portion and a lower pressurized fluid portion, and an indicator positioned at an upper part of the expansion tank in communication with the contents of the upper pressurized gas portion. The indicator is configured so as to display a first color if the operating conditions arc normal in the pressurized gas portion, and a second color if the amount of moisture detected in the pressurized gas portion greater than or equal to a predetermined amount. Further disclosed is a method for detecting whether there is an excessive amount of moisture in a pressurized gas portion of an expansion tank by allowing pressurized gas from the pressurized gas portion to come into contact with the indicator, and viewing the color displayed by the indicator. As such, the tank can be simply visually inspected to determine whether there is a potential failure in the tank.

The invention provides a metal bellows type accumulator having an outer shell provided in its one end with a pressure introducing passage in an opening manner, an axially expandable metal bellows including peak portions directed to an outer side in a radial direction and trough portions directed to an inner side alternately in an axial direction, having an axially fixed end to the outer shell and separating an inner chamber of the outer shell into a pressure introducing chamber and a gas chamber charged with cushion gas, and a support member arranged in an inner periphery of the metal bellows, fixed to the outer shell and constructed by a cushioning member. A clearance in a radial direction between the trough portions of the metal bellows and the support member is smaller than a clearance in a radial direction between the peak portions of the metal bellows and the outer shell.

The invention provides a metal bellows type accumulator having an outer shell provided in its one end with a pressure introducing passage in an opening manner, an axially expandable metal bellows including peak portions directed to an outer side in a radial direction and trough portions directed to an inner side alternately in an axial direction, having an axially fixed end to the outer shell and separating an inner chamber of the outer shell into a pressure introducing chamber and a gas chamber charged with cushion gas, and a support member arranged in an inner periphery of the metal bellows, fixed to the outer shell and constructed by a cushioning member. A clearance in a radial direction between the trough portions of the metal bellows and the support member is smaller than a clearance in a radial direction between the peak portions of the metal bellows and the outer shell.