Stator Blade Ring Segmented Welding Heat Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional stator blade ring assembly methods in axial-flow compressors lead to thermal deformation due to excessive heat input during electron beam welding, affecting airflow and compression efficiency.
Innovation Solution
The method involves circumferentially splitting the inner and outer shrouds to form segment pieces, with a band-shaped coupling member placed in grooves on the opposite side of the stator blade, allowing for discontinuous welding that reduces heat input and minimizes thermal deformation by dissipating heat and reducing residual stress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If electron beam welding is performed from the side surface of the shroud to the center of the stator blade over the entire circumference, then the stator blade ring is joined together, but thermal deformation of the stator blade and shroud occurs
Solution Approach 1:
The stator blade ring is divided into multiple segment pieces (e.g., 4 segments), each containing a stator blade and portions of the inner and outer shrouds. These segments are assembled and welded separately, then joined together to form the complete ring. This segmentation reduces the heat input per welding operation and allows heat dissipation between welds, preventing thermal deformation while maintaining joint strength.
Solution Approach 2:
The welding process is performed periodically on discrete segments rather than continuously around the entire circumference. After welding each segment, the process pauses to allow heat dissipation before proceeding to the next segment. This periodic action prevents heat accumulation and the resulting thermal deformation.
2Stability of the object's composition
If continuous electron beam welding is performed around the entire stator blade ring, then complete joining is achieved, but heat accumulates causing deformation
Solution Approach 1:
The continuous welding process is replaced by segmented welding operations. The stator blade ring is divided into discrete segments that are welded separately at different locations and times. This ensures structural integrity through complete joining while preventing heat accumulation by allowing thermal dissipation between weld operations.
Solution Approach 2:
Jigs and fixtures are used as intermediaries to hold and position the segment pieces during assembly and welding. These intermediaries provide stable support and precise positioning, ensuring structural integrity during the discontinuous welding process while allowing heat to dissipate without causing deformation.
3Ease of manufacture
If the shroud deforms due to welding heat, then the stator blade ring can be assembled, but airflow in the cabin is disturbed reducing compression efficiency
Solution Approach 1:
The shroud is divided into multiple segments that are welded separately and then assembled into the complete ring. This segmentation allows each segment to be welded with controlled heat input, preventing thermal deformation that would disturb airflow. The segmented approach maintains assembly feasibility while preserving compression efficiency by ensuring the shroud surface remains smooth and aerodynamically correct.
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 approach prevents deformation of the stator blade and shroud, maintaining airflow stability and enhancing compression performance by reducing thermal stress and heat accumulation during the assembly process.
Implementation Method 1
electron beam welding from side surfaces of an inner shroud and an outer shroud
Implementation Method 2
a part of a circumferential length of the segment piece is welded to the coupling member
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention has an object to provide an assembling method of a stator blade ring segment that can prevent the risk of thermal deformation and a reduction in strength, ensure flexibility of shape, and increase compression performance of a compressor. The present invention has another object to provide welding that prevents an object to be welded from rising from a groove or a recess during welding and allows satisfactory welding. A groove 50 formed in each segment piece 41 is formed to have side wall portions 50b on opposite sides inclined with respect to a bottom 50a so that a width of the groove 50 gradually decreases from an outer peripheral side toward the bottom 50a, and a coupling member 42 has a sectional shape so as to have a maximum width at protrusions 42b at an intermediate portion in a thickness direction. The protrusions 42b on the opposite sides abut against or approach the side wall portions 50b of the groove 50 when the coupling member 42 is placed in the groove 50, a space 100 is formed on the side of the bottom 50a of the groove 50, and a welding groove 200 having a substantially V-shaped section is formed on the side remote from the bottom 50a of the groove 50.