A bellows accumulator, consisting of at least one accumulator housing (2) and having a separating bellows (20) which is movably arranged in the accumulator housing (2) and has a plurality of bellows folds and separates two media spaces (8, 22) from one another, wherein the stationary open end of said separating bellows (20) is fixed to the accumulator housing (2) by means of a securing device (24) and wherein said separating bellows (20) has at its movable other end a closure part (36) having a guide device (40) by means of which the closure part (36) is guided in the accumulator housing (2), is characterized in that the closure part (36) has, in addition to the guide device (40), a sealing device which, at least in the one extended end position of the separating bellows (20), separates a fluid space (8), in which the bellows folds are arranged in the accumulator housing (2), from a fluid port (12) in the accumulator housing (2) and, at least in some of the other working positions, releases this fluid connection.

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 has at least one accumulator housing (2) and a separating bellows (20) movably arranged in the accumulator housing (2). The separating bellows 20 has a plurality of bellows folds and separates two media spaces (8, 22) from one another. The stationary open end of the separating bellows (20) is fixed to the accumulator housing (2) by a securing device (24). The separating bellows (20) has, at its movable other end, a closure part (36) having a guide device (40) by which the closure part (36) is guided in the accumulator housing (2). The closure part (36) has, in addition to the guide device (40), a sealing device (50). At least in the one extended end position of the separating bellows (20), the sealing device (50) separates a fluid space (8), in which the bellows folds are arranged in the accumulator housing (2), from a fluid port (12) in the accumulator housing (2). At least in some of the other working positions, the sealing device (50) releases this fluid connection.

The present invention provides lightweight high-pressure accumulators that avoids diaphragm failure observed in conventional diaphragm accumulators. Lightweight high-pressure composite overwrapped accumulators of the invention are made from a plurality of hollow casings that are mated to form an accumulator housing. The accumulator housing is overwrapped with a composite material to provide additional mechanical strength and structural integrity. More significantly, the accumulators of the invention includes a plurality of annular grooves and a plurality of bulb on the flexible diaphragm such that the plurality of bulbs on the flexible diaphragm are placed in the plurality of annular grooves that are formed between the first and the second hollow casing. In this manner, diaphragm failure is significantly reduced or even completely eliminated during repeated high pressure charge/discharge cycle of the accumulator.

A method for the combined pump water pressure-compressed air energy storage at a constant turbine water pressure, the energy to be stored is used to pump a liquid medium into a pressure vessel such that a rising level of medium compresses the gas contained in the pressure vessel through a connecting conduit and presses said gas into a compressed gas tank, the conduit being shut using a check valve such that the energy is stored in the compressed gas.

An electrohydraulic system for use under water includes an electrohydraulic actuator and a container having an internal space provided for forming a volume which is enclosed from the environment and which is provided for receiving a hydraulic pressurized fluid. A hydraulic cylinder is provided in the internal space of the container, the inside of which is divided into a first cylinder chamber and a second cylinder chamber by a piston to which a first piston rod and a second piston rod are connected. The two active surfaces of the piston are the same or approximately the same size.

The present disclosure provides a gas-liquid coupling type fluid pulsation attenuator, which comprises: substrate, which is hollow and with an opening at one end; bladder, which is located at the hollow part of the substrate, and a first chamber is formed between the bladder and the inner wall of the substrate; and lining, which is located inside the bladder. The gas-liquid coupling type fluid pulsation attenuator of the present disclosure makes the fluid in the main pipe enter the first chamber through the opening of the substrate, and the bladder is filled with gas. Therefore, under the action of the pressure difference between the fluid pressure in the first chamber and the air pressure in the bladder, the bladder deforms, so as to absorb the flow pulsation through the expansion and contraction of the bladder, to make the oil flow in the hydraulic energy system more stable.

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.