Combustor Cylinder Rib Welding for Crack Prevention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

One-side welding of ribs in combustor cylinders can lead to crack growth under high pressure, necessitating improved bonding strength to prevent damage.

Innovation Solution

Welding rib end portions from both sides in the axial direction to both the cylinder body and jacket plate, with a rib structure that includes multiple rib bodies connected by bridge portions and a jacket plate divided into separate components for easier welding, reducing bending stress and enhancing fixation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ribs are welded only from one side in the axial direction, then the manufacturing process is simpler and faster, but the bonding strength is insufficient and cracks may grow under high pressure

Engineering Contradiction:
Improvebonding strength of ribVSAvoidwelding process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The jacket plate is divided into a first jacket plate and a second jacket plate positioned on opposite sides of the rib. This segmentation enables welding to be performed from both sides of the rib in the axial direction, improving bonding strength while making the welding process accessible from both sides.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The welding approach transitions from single-sided welding to double-sided welding by utilizing the axial dimension. The first and second jacket plates are positioned on opposite sides along the axial direction, allowing welds to be applied from both ends of the rib.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Ease of operation

If a single jacket plate is used, then the structure is simpler, but welding access from both sides is restricted

Engineering Contradiction:
Improvewelding accessibilityVSAvoidjacket plate structure
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The jacket plate is segmented into two separate components (first and second jacket plates) that can be positioned on opposite sides of the rib. This segmentation provides access to both sides of the rib for welding operations while maintaining structural integrity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The first and second jacket plates are prepared in advance and positioned on opposite sides of the rib before welding. This preliminary positioning enables simultaneous or sequential welding from both sides, improving accessibility and welding quality.

Inventive Principle:
Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This configuration firmly fixes the rib to the cylinder body and jacket plate, reducing the likelihood of crack growth and maintaining stability under high-pressure fluid loads, while also simplifying the manufacturing process and reducing operation costs.

Implementation Method 1

The rib is connected to the cylinder body by a cylinder side end portion on the cylinder body side in a radial direction with respect to an axis of the cylinder body being welded from both sides in an axial direction of the axis. The rib is connected to the jacket plate by a jacket side end portion on the jacket plate side in the radial direction being welded from both sides in the axial direction.

Methodology Applied
Scientific EffectWelding: Welding

Data Source

PatentEP3171089B1Cylinder of combustor, method of manufacturing of cylinder of combustor, and pressure vessel
Publication Date: 2019.08.21 MITSUBISHI HITACHIPOWER SYST LTD
  • EP3171089B1 patent drawingFigure 1
  • EP3171089B1 patent drawingFigure 2
  • EP3171089B1 patent drawingFigure 3

AI summary

A combustor cylinder is provided with: a cylinder body (4), through the inside of which combustion gas flows; a jacket plate (61) for covering the cylinder body (4) from the outside and forming a fluid space (FS) between the inner peripheral surface of the jacket plate (61) and the outer peripheral surface of the cylinder body (4), the fluid space (FS) allowing high-pressure fluid to flow thereinto; and a rib (62) for connecting the cylinder body (4) and the jacket plate (61), The rib (62) is configured in such a manner that: the cylinder-side end (621a) thereof which is located on the cylinder body (4) side in the radial direction referenced to the axis of the cylinder body (4) is welded from both sides in the axial direction along the axis and connected to the cylinder body (4); and the jacket-side end section (621b) thereof which is located on the jacket plate (61) side in the radial direction is welded from both sides in the axial direction and connected to the jacket plate (61).