A bellows accumulator, consisting of at least two housing parts (4, 6) which form an accumulator housing (2), and having a separating bellows (20), which is movably arranged in the accumulator housing (2) and separates two media spaces (8, 22) from each other and is at least on its one free end fixed to a securing device (24) in the accumulator housing (2), wherein said securing device (24) is welded to the adjacently arranged housing parts (4, 6), is characterized in that the adjacently arranged housing parts (4, 6) comprise at least in part titanium materials, in that the securing device (24) consists of at least two interconnected components (26, 30), at least one (26) of which comprises at least in part titanium materials and is welded to the adjacently arranged housing parts (4, 6), and in that the respective other component (30), consisting of a different metal material, is used for securing the separating bellows (20) to the securing device (24).

A bellows accumulator, consisting of at least two housing parts (4, 6) which form an accumulator housing (2), and having a separating bellows (20), which is movably arranged in the accumulator housing (2) and separates two media spaces (8, 22) from each other and is at least on its one free end fixed to a securing device (24) in the accumulator housing (2), wherein said securing device (24) is welded to the adjacently arranged housing parts (4, 6), is characterized in that the adjacently arranged housing parts (4, 6) comprise at least in part titanium materials, in that the securing device (24) consists of at least two interconnected components (26, 30), at least one (26) of which comprises at least in part titanium materials and is welded to the adjacently arranged housing parts (4, 6), and in that the respective other component (30), consisting of a different metal material, is used for securing the separating bellows (20) to the securing device (24).

A fluid tank includes polymeric liner comprising an upper wall and a lower wall. The upper wall and the lower wall define a cavity therebetween. A weld joint joins the upper and lower walls together. A method for assembling a fluid tank includes overlapping surfaces of an upper wall and a lower wall to form a liner defining a cavity. The method includes joining the surface of the upper wall and the surface of the lower wall together by welding to form a weld joint between the upper wall and the lower wall. The method can include cooling the weld joint to control warpage of the liner at the weld joint.

A bellows accumulator, consisting of at least two housing parts (4, 6) which form an accumulator housing (2), and having a separating bellows (20), which is movably arranged in the accumulator housing (2) and separates two media spaces (8, 22) from each other and is at least on its one free end fixed to a securing device (24) in the accumulator housing (2), wherein said securing device (24) is welded to the adjacently arranged housing parts (4, 6), is characterized in that the adjacently arranged housing parts (4, 6) comprise at least in part titanium materials, in that the securing device (24) consists of at least two interconnected components (26, 30), at least one (26) of which comprises at least in part titanium materials and is welded to the adjacently arranged housing parts (4, 6), and in that the respective other component (30), consisting of a different metal material, is used for securing the separating bellows (20) to the securing device (24).

A bellows accumulator, consisting of at least two housing parts (4, 6) which form an accumulator housing (2), and having a separating bellows (20), which is movably arranged in the accumulator housing (2) and separates two media spaces (8, 22) from each other and is at least on its one free end fixed to a securing device (24) in the accumulator housing (2), wherein said securing device (24) is welded to the adjacently arranged housing parts (4, 6), is characterized in that the adjacently arranged housing parts (4, 6) comprise at least in part titanium materials, in that the securing device (24) consists of at least two interconnected components (26, 30), at least one (26) of which comprises at least in part titanium materials and is welded to the adjacently arranged housing parts (4, 6), and in that the respective other component (30), consisting of a different metal material, is used for securing the separating bellows (20) to the securing device (24).

1. Separator element

2. A separator element consisting of at least two types of layers of plastic material, one type of which layers is media resistant to mineral oils; and the other type of which layers has low permeability to gases or is gas-tight,
wherein the two types of layers are firmly bonded to each other when in direct contact and form the elastically flexible separator element (12).

1. Separator element

2. A separator element consisting of at least two types of layers of plastic material, one type of which layers is media resistant to mineral oils; and the other type of which layers has low permeability to gases or is gas-tight,
wherein the two types of layers are firmly bonded to each other when in direct contact and form the elastically flexible separator element (12).

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 are 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.

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 are 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.

A diaphragm accumulator provided with a flexible diaphragm inside an accumulator housing has a stress relaxing member having a contact surface which the diaphragm deformed by a pressure fluctuation inside the accumulator housing contacts and regulating the deformed attitude of the diaphragm by the contact surface on the inner surface. When the diaphragm is deformed by the pressure fluctuation inside the accumulator housing, the stress relaxing member regulates the deformed attitude of the diaphragm to reduce a stress generated in the diaphragm.