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.

An accumulator includes a pressure vessel and a partition portion separating an interior space of the pressure vessel into a liquid chamber and a gas chamber so that a volume ratio between the liquid chamber and the gas chamber in the pressure vessel is variable. The pressure vessel includes a first section including a thread portion for fastening the accumulator to a support member and a second section joined to the first section and formed by a single piece including a tool engagement portion capable of engaging with a tool for rotating the accumulator. The first section and the second section are fitted together by mating portions coaxial with the thread portion and the tool engagement portion.

An accumulator includes a pressure vessel including a first section and a second section joined to each other via a joint portion and a partition portion separating an interior space of the pressure vessel into a liquid chamber and a gas chamber so that a volume ratio between the liquid chamber and the gas chamber in the pressure vessel is variable. The first section includes a thread portion for fastening the accumulator to a support member. The second section includes an abutting portion disposed opposite to the thread portion across the joint portion in an axial direction of the thread portion and configured to abut on the support member when the accumulator is fastened to the support member.

The disclosure relates to a hydraulic accumulator, in particular a diaphragm accumulator, comprising an accumulator housing and a separating element which is arranged therein and separates two media chambers from each other. The accumulator housing has at least one fluid connection point which opens into an adjacent media chamber and has a connection body with a fluid passage point that is connected to the accumulator housing via a welding seam. The connection body has an annular outer circumferential surface on the connection region facing the accumulator housing, and when the end face of the connection body is placed on the accumulator housing, the connection body forms a transition point, along which the welding seam runs.

An accumulator has a pressure vessel, a partition portion comparting an internal space of the pressure vessel into a gas chamber having sealed gaseous matter and a liquid chamber having introduced liquid, and a bellows connected to the partition portion. The partition portion is provided with a bellows connection portion connected to the bellows, a seal arranged in a liquid chamber side of the bellows connection portion, and a seal retention portion fixed to the bellows connection portion and retains the seal. The seal retention portion is constructed by a leaf spring which is elastically deformable in a part thereof, and is structured by integrally forming a fixed portion fixed to the bellows connection portion, and a retention portion retaining the seal. Accordingly, the accumulator can reduce the number of parts of a pressure fluctuation absorbing mechanism, can be easily assembled, and can reduce a parts cost.

A shell member 10 constituting an accumulator 100 including a cover member 30, a shell member 10 having a cylindrical portion 11, an opening portion 13 formed at one end of the cylindrical portion 11 and welded to the cover member 30, and a closed portion 12 formed at another end of the cylindrical portion 11, and an accumulation part 70 accommodated in the shell member 10. The cylindrical portion 11 includes an upper end portion 11a, and a protruding portion 11c having the opening portion 13. The protruding portion 11c is thicker than the upper end portion 11a.

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.

The invention relates to a method for producing pressure vessels, including pressure accumulators, such as hydraulic accumulators and parts thereof (24), characterized in that they are at least partially produced by means of a 3D printing method.

The invention relates to a method for producing wall parts (24) of a housing for pressure vessels by means of a 3-D printing method, wherein material is applied layer-by-layer in order to form each wall part (24). Said method is characterized in that, in case of wall part geometries (28) that lead to distortions (44) that impede the application of material, the layer thickness in the application of material must be selected in such a way that the particular distortion (44) is avoided and that the formation of wall part geometries (28) that are critical in this respect is performed without support parts.

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.