Radially Movable Segments in Forging Dies
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The forging of large powder metallurgy billets for gas turbine components is hindered by high frictional forces at the die-billet interface, leading to cracking due to tangential stresses, which existing solutions like varying die temperature and forging strain rates have not adequately addressed.
Innovation Solution
A forging die with radially movable segments and a backplate assembly that promotes radial growth by allowing free radial movement, reducing friction and cracking incidence, and accommodating varying billet sizes through concentric bands and lubrication for improved deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional forging dies with fixed surfaces are used, then the die structure is simple and easy to manufacture, but high frictional forces develop at the die-billet interface impeding radial growth and causing cracking
Solution Approach 1:
The forging die is divided into multiple radially movable segments that can independently move relative to each other and the backplate. This segmentation allows the die to accommodate radial growth of the billet during forging while reducing frictional forces, thereby preventing cracking without requiring a completely new die design
Solution Approach 2:
The die segments are made movable rather than fixed, allowing them to dynamically adjust during the forging process. The segments can move radially outward as the billet expands, maintaining lower frictional contact and enabling free radial growth, which resolves the contradiction between simple structure and crack prevention
2Productivity
If traditional forging methods are used on powder metallurgy billets, then the process is straightforward, but high frictional forces impede radial growth and result in cracks
Solution Approach 1:
By segmenting the die into movable parts, the system maintains straightforward operation while enabling the billet to expand radially during forging. The segments move outward to accommodate material flow, reducing friction and preventing cracks, thus improving both productivity and reliability
Solution Approach 2:
The die interface parameters are changed from fixed to movable, allowing the contact conditions to change during forging. This parameter change enables the die to adapt to the billet's radial growth, reducing frictional forces and preventing cracking while maintaining efficient forging operations
3Reliability
If radial movement of segments is restricted, then the die structure is simpler, but frictional forces increase and cracking occurs
Solution Approach 1:
The die is segmented into multiple independent movable segments, each capable of radial movement. This segmentation creates a mechanism that is more complex than a fixed die but still relatively simple in implementation, providing crack resistance through the ability of segments to move outward during forging
Solution Approach 2:
The segments are designed with dynamic movement capability along radial guides, allowing them to move outward as the billet expands. This dynamic feature adds some complexity to the die structure but is sufficient to prevent cracking by reducing frictional forces, achieving the right balance between simplicity and reliability
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
The solution significantly reduces cracking in large forgings, enabling more uniform properties and lower material losses, making it feasible to forge high-strength alloys that were previously difficult to process, thus enhancing design efficiency and reducing scrap.
Implementation Method 1
high frictional forces that develop at the die-billet interface and impede free radial growth of the billet
Data Source
Figure 1~2
Figure 3~4
AI summary
A forging die (10) and process suitable for producing large forgings, including turbine disks and other rotating components of power-generating gas turbine engines, using billets (40) formed by powder metallurgy. The forging die (10) includes a backplate (12), and segments (14) arranged in a radial pattern about a region (16) on a surface of the backplate (12). Each segment (14) has a backside (20) facing the backplate (12) and an interface surface (18) facing away from the backplate (12), with the interface surface (18) being adapted to engage the billet (40) during forging. The segments (14) are physically coupled to the surface of the backplate (12) in a manner that enables radial movement of the segments (14) relative to the backplate (12).