Stepped Forming Mandrel for Hollow Body Wall Profile Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing wall profiles on hollow bodies result in cross-sectional narrowing due to material-induced elastic recovery or additional component attachment, making it difficult to insert a counterpart into the cavity.
Innovation Solution
Employ a stepped forming mandrel with varying cross-sections to compensate for elastic recovery and ensure a uniform cavity size, using a forming die to reproduce the mandrel profile on the hollow body wall, and optionally use a clamping device to inhibit movement during the forming process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a uniform cross-section forming mandrel is used, then the forming process is simple, but the cavity cross-section narrows due to elastic recovery making insertion difficult
Solution Approach 1:
The forming mandrel is designed with varying cross-sections along its length, where different sections have different dimensions to compensate for localized elastic recovery effects. This allows the cavity to maintain a more uniform cross-section after forming, facilitating easier insertion of counterparts while addressing the narrowing problem in specific regions.
Solution Approach 2:
The forming mandrel pre-compensates for elastic recovery by having an enlarged cross-section in regions where recovery is expected to occur. This preliminary action ensures that after the forming process and elastic recovery, the cavity achieves the desired uniform cross-section, preventing insertion difficulties before they occur.
2Adaptability or versatility
If additional components are attached to the hollow body wall, then functionality is enhanced, but the cavity cross-section narrows making insertion more difficult
Solution Approach 1:
The forming mandrel incorporates varying cross-sections that account for the space occupied by additional components. By enlarging the mandrel cross-section in regions where components will be attached, the cavity maintains sufficient clearance for counterpart insertion even after component attachment, thus preserving ease of operation while enabling functional adaptability.
3Manufacturing precision
If the forming mandrel cross-section is enlarged to compensate for elastic recovery, then cavity uniformity improves, but the forming die force increases
Solution Approach 1:
Instead of uniformly enlarging the entire mandrel cross-section, the invention applies localized cross-sectional enlargements only in specific regions where elastic recovery is anticipated. This selective approach achieves the desired cavity uniformity while minimizing the overall forming force required, as the die only needs to exert additional force in the affected regions rather than along the entire length.
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
Ensures a uniform cavity size by compensating for elastic recovery and accommodating additional components, facilitating easy insertion of counterparts by maintaining a matched cross-section.
Implementation Method 1
material of the hollow body wall is plasticized due to the forming movement of the forming die, and the forming mandrel profile is reproduced on the inside of the hollow body wall as the wall profile
Implementation Method 2
a material-induced non-uniform elastic recovery of the hollow body wall over the length of the formed hollow body, which occurs automatically when the forming mandrel is removed from the interior of the hollow body after completion of the forming process
Data Source
AI summary
In order to produce a wall profile on an inside of a plastically deformable hollow body wall of a hollow body, a forming mandrel is arranged in the interior of a cavity of the hollow body so that the forming mandrel extends at the level of a first longitudinal portion of the hollow body wall with a mandrel portion having an enlarged cross-section, which has a forming mandrel profile portion and a cross-sectional oversize compared to a mandrel portion having a reduced cross-section, which extends at the level of a second longitudinal portion of the hollow body wall and has a further forming mandrel profile portion. A forming die is moved with a forming movement relative to the hollow body wall and relative to the mandrel portion with an enlarged cross-section and relative to the mandrel portion with a reduced cross-section of the forming mandrel.