In-Situ Repair of Vehicle Megacastings by Partial Section Replacement

Solution Overview

Problem

The existing methods for repairing ultra-large single-piece castings in vehicle body components require the entire casting to be removed and replaced when damaged, which is inefficient and complex, especially for mega- or giga-castings used in modern electric vehicles.

Innovation Solution

A method involving the localization of damaged areas, determination of cut-lines to avoid or include load-bearing structures, excision of damaged portions, and joining of replacement pieces using structural adhesives, welding, or additive manufacturing techniques such as Direct Energy Deposition directly onto the undamaged portion, ensuring minimal disruption and maintaining structural integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the entire ultra-large single-piece casting is removed and replaced when damaged, then the structural integrity and safety are ensured, but the manufacturing complexity and time consumption increase significantly

Engineering Contradiction:

Improvestructural integrityVSAvoidreplacement time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The casting is divided into two segments: the damaged portion to be removed and the undamaged portion to be retained. A cut line is defined to separate these portions, allowing only the damaged segment to be excised while preserving the intact structure. This segmentation enables partial replacement rather than complete replacement, significantly reducing time loss while maintaining structural integrity through proper joining of the replacement piece to the retained portion.

Inventive Principle:

Principle #1Segmentation

2Reliability

If the entire ultra-large single-piece casting is removed and replaced when damaged, then the structural integrity and safety are ensured, but the manufacturing complexity and resource consumption increase

Engineering Contradiction:

Improvestructural integrityVSAvoidmanufacturing complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The casting is divided into two segments: the damaged portion to be removed and the undamaged portion to be retained. A cut line is defined to separate these portions, allowing only the damaged segment to be excised while preserving the intact structure. This segmentation enables partial replacement rather than complete replacement, significantly reducing time loss while maintaining structural integrity through proper joining of the replacement piece to the retained portion.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Only the damaged portion is extracted from the casting using the defined cut line as a boundary. The extraction process removes solely the defective segment while leaving the sound structure intact. This selective extraction reduces manufacturing complexity by avoiding the need to handle, transport, and install an entire ultra-large casting, thereby reducing resource consumption and operational complexity.

Inventive Principle:

Principle #2Taking out (Extraction)

3Reliability

If a conservative cut line is used to avoid load bearing structures, then the structural integrity is maintained, but the repairability and flexibility are reduced

Engineering Contradiction:

Improvestructural integrityVSAvoidrepairability

Core Design Contradiction:

ReliabilityVSEase of repair

Solution Approach 1:

The cut line definition incorporates local quality assessment by evaluating the proximity to load bearing structures at different locations. The cut line is positioned to maintain adequate distance from critical load bearing elements where structural integrity must be preserved, while allowing closer proximity or inclusion of non-critical portions in the damaged area to be removed. This localized quality control enables optimal balance between maintaining structural integrity and maximizing repairability by removing sufficient damaged material.

Inventive Principle:

Principle #3Local quality

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

Enables in-situ repair of ultra-large castings without the need for complete replacement, maintaining or improving the mechanical performance of the repaired component, and simplifying the repair process by allowing for on-site fabrication and integration of replacement parts.

Implementation Method 1

using a Direct Energy Deposition additive manufacturing to fabricate the replacement piece directly onto the undamaged portion of the cast component

Methodology Applied

Scientific EffectDirect Energy Deposition:

Implementation Method 2

joining the replacement piece to the undamaged portion of the cast component using a structural adhesive

Methodology Applied

Scientific EffectAdhesion: Adhesive

Data Source

PatentUS12097583B2Method of in-situ repair of an ultra-large single-piece casting

Publication Date: 2024.09.24 GM GLOBAL TECHNOLOGY OPERATIONS LLC

AI summary

A method of repairing an ultra-large single-piece cast component of a vehicle body. The method includes the steps of locating a damaged portion of the cast component, determining an extent of the damaged portion of the ultra-large cast component, defining a cut-line sectioning off the damaged portion from an undamaged portion of the ultra-large cast component, cutting along the cut-line to excise the damaged portion from the undamaged portion of the ultra-large cast component, and joining a replacement piece to the undamaged portion of the ultra-large cast component. The replacement piece is fabricated based on the original manufacturer's geometry and dimensional data of the excised damaged portion. The undamaged portion of the ultra-large cast component remains on the vehicle body during the repair.