Pressure cylinder made of a thin-walled welded stainless steel vessel and its production method

Abstract

A pressure cylinder made of thin-walled welded stainless steel vessel fitted with a composite shell and a neck with an external and/or internal thread, where the neck is attached to the thin-walled vessel by a circular welded seam with a hermetic seal and containing a flange which is fitted circumferentially with a pair of tapered grooves on its outer surface whose adjacent sides meet on an annular ridge on which there are locking teeth in the direction of the longitudinal axis of the neck and composite fibers are placed in inter-tooth spaces. The method of producing a pressure cylinder includes the welding of a neck to the thin-walled vessel with a hermetic seal, whereupon composite fibers with stress less than the total force acting on the fiber bundle are wound into additional grooves between the teeth and further winding of the fiber around the neck is carried out while simultaneously moving bilaterally along the axis of the shell to position the fiber between the teeth, whereupon fibers with a nominal stress value are wound and final winding of the reinforced composite shell is carried out.

Claims

1. A pressure cylinder made of thin-walled welded stainless steel vessel (1) with a composite shell and a neck (2) with an external and/or internal thread, characterized in that the neck (2) is attached to the thin-walled vessel (1) by a circular welded seam with a hermetic seal and containing a flange which is fitted circumferentially with a pair of tapered grooves (3) on its outer surface whose adjacent sides meet on an annular ridge on which there are locking teeth in the direction of the longitudinal axis of the neck (2) and composite fibers are placed in inter-tooth spaces (4, 5).

2. The pressure cylinder according to claim 1, characterised in that the inter-tooth spaces (4, 5) have a shape selected from the group trapezoidal groove, U-shaped groove, and tapered hole in the transverse direction.

3. A method of producing a pressure cylinder according to claim 1, characterised in that a neck is welded to the thin-walled vessel with a hermetic seal, which contains a flange which is fitted circumferentially with a pair of tapered grooves on its outer surface meeting on an annular ridge on which there are locking teeth, whereupon composite fibers with stress less than the total force acting on the fiber bundle are wound into additional grooves between the teeth and then around the shell, and further winding of the fiber around the neck is carried out while simultaneously moving bilaterally along the axis of the shell to position the fiber between the teeth, whereupon fibers with a nominal stress value are wound, and final winding of the reinforced composite shell is carried out.

4. The method of producing a pressure cylinder according to claim 3, characterised in that the number of winding cycles with stress less than the total force acting on the fiber bundle corresponds to the number of additional grooves between the teeth.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] According to the present invention, the pressure cylinder will be described in more detail using specific exemplary embodiments using the accompanying drawings, where

[0017] FIG. 1 shows an exemplary cylinder in a side view.

[0018] FIGS. 2a and 3a show details of the neck and FIGS. 2b and 3b show this neck in the corresponding section.

[0019] FIGS. 4a and 4b show various grooves on the neck flange in an axonometric view.

[0020] FIG. 5 shows a view of the cylinder in the direction of the neck, and

[0021] FIG. 6 shows details of the fibers and neck.

DETAILED DESCRIPTION

[0022] An exemplary pressure cylinder made of thin-walled welded stainless steel vessel 1 with a reinforced composite shell and neck 2 with an external thread, neck 2 is attached to the thin-walled vessel 1 by a circular welded seam with a hermetic seal. Neck 2 contains a flange which is fitted circumferentially with a pair of tapered grooves 3 on its outer surface whose adjacent sides meet on an annular ridge on which there are locking teeth in the direction of the longitudinal axis of the neck 2, and composite fibers are placed in the inter-tooth spaces 4, 5. The inter-tooth spaces 4, 5 have the shape of a trapezoidal groove in the transverse direction in one embodiment and a tapered groove in the other.

[0023] During the production of the pressure cylinder, neck 2 is welded to the thin-walled vessel 1 with a hermetic seal, which contains a flange which is fitted circumferentially with a pair of tapered grooves 3 on its outer surface meeting on an annular ridge on which there are locking teeth, whereupon composite fibers with stress less than the total force acting on the fiber bundle are wound into further grooves 4 and 5 between the teeth and then around the shell, and further winding of the fiber around the neck 2 is carried out while simultaneously moving bilaterally along the axis of the shell to position the fiber between the teeth, whereupon the fibers with a nominal stress value are wound and final winding of the reinforced composite shell is carried out. The number of winding cycles with stress less than the total force acting on the fiber bundle corresponds to the number of grooves between the teeth.

[0024] The combination of a thin-walled stainless steel liner and a reinforced composite shell made of high-strength carbon enables the production of a lightweight cylinder, which is very important when used as a storage tank for oxygen and other gases in the aerospace industry.

[0025] In addition, this technical solution will increase the structure's operational safety and reduce the weight of the reinforced shell in the neck area due to a more rational use of the properties of the composite material.

[0026] According to this technical solution, the pressure cylinder finds its application mainly in the aerospace industry, divers, firefighters, and the like.