Method for producing a barrier layer of a pressure vessel, and pressure vessel

Abstract

A method of producing a barrier layer of a pressure vessel includes applying the barrier layer to a liner and/or to a fiber-reinforced layer of the pressure vessel while a pressure difference between the internal volume and the surroundings of the pressure vessel is being maintained.

Claims

1. A method for the production of a barrier layer of a pressure vessel having an internal volume, comprising the steps of: generating a pressure difference between the internal volume and an exterior surrounding of the pressure vessel; and applying the barrier layer to an interior surface of the pressure vessel while the pressure difference is being maintained such that the barrier layer is under compression in one or both of an axial direction and a circumferential direction when the pressure vessel is not pressurized.

2. The method according to claim 1, wherein the pressure difference is at least 10% of a nominal operating pressure of the pressure vessel.

3. The method according to claim 1, wherein the pressure difference is maintained at a predetermined pressure level that results in at least 10% expansion of the surface to which the barrier layer is being applied relative to an amount of expansion the pressure vessel would undergo when exposed to the nominal operating pressure of the pressure vessel.

4. The method according to claim 3, wherein the barrier layer is provided internally relative to one or both of a fiber-reinforced layer and a liner of the pressure vessel.

5. The method according to claim 3, wherein the barrier layer is applied to a plastics liner of the pressure vessel.

6. The method according to claim 5, wherein the pressure difference is at least 10% of a bursting pressure of the plastics liner.

7. The method according to claim 1, wherein the barrier layer is a metal layer.

8. A pressure vessel for the storage of fuel which is gaseous under ambient conditions, comprising a barrier layer produced according to the method of claim 1.

9. The pressure vessel according to claim 8, wherein the barrier layer is configured to undergo a change from a state of compression in the circumferential and axial directions to a state of expansion when pressure in the internal volume is greater than a predetermined internal pressure threshold, the predetermined internal pressure threshold having a value within 1% to 150% of the nominal operating pressure of the pressure vessel.

10. The pressure vessel according to claim 9, wherein the predetermined internal pressure threshold having a value within 20% to 140% of the nominal operating pressure of the pressure vessel.

11. The pressure vessel according to claim 9, wherein the predetermined internal pressure threshold having a value within 50% to 130% of the nominal operating pressure of the pressure vessel.

12. The pressure vessel according to claim 8, wherein the barrier layer is arranged internally relative to one or both of a fiber-reinforced layer and a liner of the pressure vessel.

13. The pressure vessel according to claim 8, wherein the barrier layer is applied to a plastics liner of the pressure vessel.

14. The pressure vessel according to claim 8, wherein the barrier layer is a metal layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagrammatic longitudinal sectional view of a pressure vessel 100 in accordance with the present invention, along the section line B-B of FIG. 2, and

(2) FIG. 2 is a diagrammatic cross-sectional view of the pressure vessel 100 of FIG. 1, along the section line C-C of FIG. 1.

DETAILED DESCRIPTION

(3) FIG. 1 shows a pressure vessel 100 according to the technology disclosed herein. The pressure vessel 100 comprises a plastics liner 110 (for which the term liner is also generally used herein), surrounded by a fiber-reinforced layer 120, also termed reinforcement. Provided here coaxially in relation to the longitudinal axis A-A of the pressure vessel is a pressure-vessel outlet in which the tank valve 170 has been inserted. In a central region M, the pressure vessel 100 comprises a cylindrical curved surface, at the two edges of which there is in each case a cap-shaped end P1, P2 provided. The pressure vessel 100 here is configured cylindrically. However, this is not an essential requirement. Other shapes are equally conceivable. Provided here on the internal side of the liner 110 is the barrier layer 130. The term permeation-barrier layer could also be used for the barrier layer 130. The barrier layer 130 and, respectively, the liner 110 surround the internal volume I of the pressure vessel 100 here; that volume serves for the storage of fuel. The barrier layer 130 here is configured from metal. It is equally conceivable that the barrier layer 130 has been produced from another material. Only one barrier layer 130 is shown here. It is equally conceivable that there are a plurality of barrier layers 130 provided, on top of one another or at various locations within the pressure vessel 100. It is equally conceivable that the barrier layer 130 has not been applied internally, but instead has been applied within the pressure-vessel wall (e.g. outside the plastics liner 110) or on the external surface of the pressure vessel 100 (e.g. on the external surface of the fiber-reinforced layer 120).

(4) The internal diameter d of the liner 110 is moreover shown. If the internal volume I is now subjected to pressure during the production of the barrier layer 130, the liner 110 then expands (not shown here) and the internal diameter d increases. In this expanded state, the barrier layer 130 is now applied. Once the barrier layer 130 has been applied, the internal pressure is in turn reduced. The internal diameter d is therefore also reduced, and the barrier layer 130 is compressed. In a preferred embodiment, the barrier layer 130 is applied before the fiber-reinforced layer 120 is provided on the liner 110.

(5) The barrier layer 130, which in the unpressurized state is compressed, can advantageously be produced at low internal pressures.

(6) FIG. 2 shows a cross section through the pressure vessel 100 with the internal barrier layer 130, which here adheres to the liner 110 by way of an adhesion-promoting primer (not shown).

(7) The preceding description of the present invention serves merely for illustrative purposes, and not for the purpose of restriction of the invention. For the purposes of the invention, various changes and modifications are possible without exceeding the scope of the invention and its equivalents.