Composite Pressure Vessel Dome Reinforcement With Bulging Sections

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing pressure vessel designs, particularly in the technique described in Patent Literature 2, suffer from a gradual decrease in strength reinforcement towards the distal ends of the dome sections due to the formation of hoop dome sections with decreasing thickness.

Innovation Solution

The pressure vessel incorporates bulging sections formed by high-angle helical winding in the shoulder sections of the dome sections, which bulge radially and are continuously formed with the high-angle helical winding layer covering the cylindrical section, along with an intermediate section formed by hoop winding or near-hoop winding between the vertices of the bulging sections.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If hoop dome sections are formed with decreasing thickness toward distal ends of dome sections, then the reinforcement structure can be simplified and manufacturing can be easier, but the strength of the reinforcement in the shoulder sections gradually decreases

Engineering Contradiction:
Improveease of manufactureVSAvoidstrength
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The patent applies local quality by forming bulging sections with increased thickness specifically in the shoulder sections of the dome, while maintaining standard thickness in other areas. This localized thickening provides enhanced reinforcement exactly where the stress concentration occurs during filling and discharge operations, without requiring uniform thickness increase throughout the entire dome section, thus balancing manufacturing feasibility with localized strength requirements.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The bulging sections are formed in advance during the liner manufacturing process by controlling the molding pressure distribution. The increased thickness in the shoulder sections is built into the liner structure before the pressure vessel assembly is completed, ensuring that the reinforcement is already in place to handle the high-stress conditions that will occur during subsequent filling and discharge operations.

Inventive Principle:
Principle #10Preliminary action

2Strength

If the liner shape is modified to include thickened sections for reinforcement, then the strength in dome sections can be maintained, but the liner shape becomes more complex and may cause stress concentration

Engineering Contradiction:
ImprovestrengthVSAvoidshape
Core Design Contradiction:
StrengthVSShape

Solution Approach 1:

The patent employs curvature by forming smooth, rounded bulging sections in the shoulder areas rather than sharp corners or abrupt transitions. These curved thickened sections naturally distribute stress more evenly throughout the structure, avoiding stress concentration points that would occur with sharp geometric changes. The spherical-like curvature of the bulging sections aligns with the natural stress distribution patterns in pressure vessels under internal pressure.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Data Source

PatentEP3872386B1Pressure vessel
Publication Date: 2025.05.21 YACHIYO IND CO LTD
  • EP3872386B1 patent drawingFigure 1
  • EP3872386B1 patent drawingFigure 2
  • EP3872386B1 patent drawingFigure 3

AI summary

A pressure vessel comprises: a liner having a cylindrical section and a pair of dome sections; and a reinforcement layer constituted by a fiber-reinforced resin material and formed on the outside of the liner. The pressure vessel is characterized in that the reinforcement layer comprises: protruding sections formed so as to protrude at the dome sections by high-angle helical winding; and a central section formed by hoop winding which spans the area between each peak of the pair of protruding sections, or by approximate hoop winding in which winding is carried out at a higher angle than the high-angle helical winding.