Rail Vehicle Side Wall with Mixed Welding for Weight Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing side walls for car boxes of rail vehicles are heavy and require additional processing steps such as filling and painting, which increase production costs and weight.

Innovation Solution

A side wall design featuring a support structure with a first convertible element and a second wall element, connected via welding and laser welding connections, respectively, allowing for a lightweight construction with varying material thicknesses and a flush exterior surface.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If traditional welding methods are used for the entire outer wall, then structural strength is improved, but weight increases and production complexity increases

Engineering Contradiction:
Improvestructural strengthVSAvoidside wall weight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The outer wall is divided into different wall elements with varying material thicknesses tailored to local load requirements. High-load areas use thicker material with laser welding, while low-load areas use thinner material with spot welding, optimizing both strength and weight locally throughout the structure.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The outer wall is segmented into multiple wall elements that can be manufactured and welded separately. This allows each segment to be optimized independently for its specific structural requirements, enabling weight reduction while maintaining overall structural integrity through selective welding methods.

Inventive Principle:
Principle #1Segmentation

2Ease of manufacture

If uniform material thickness is used throughout the outer wall, then manufacturing simplicity is improved, but structural efficiency deteriorates

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidstructural efficiency
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

Different wall elements have different material thicknesses optimized for their specific structural requirements. Thicker elements are used in high-load areas while thinner elements are used in low-load areas, maximizing structural efficiency while still using standardized manufacturing processes for each element type.

Inventive Principle:
Principle #3Local quality

3Shape

If the outer surface requires filling and painting, then aesthetic appearance is improved, but production time and cost increase

Engineering Contradiction:
Improveaesthetic appearanceVSAvoidproduction time
Core Design Contradiction:
ShapeVSProductivity

Solution Approach 1:

The wall elements are designed and welded in such a way that the outer surface achieves the required aesthetic quality through the welding process itself, without requiring additional filling or painting operations. The structural welds simultaneously serve as the final surface finish.

Inventive Principle:
Principle #25Self-service

4Strength

If thicker material is used throughout the outer wall, then structural strength is improved, but weight increases

Engineering Contradiction:
Improvestructural strengthVSAvoidside wall weight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

Material thickness is optimized locally for each wall element based on its specific structural requirements. Thicker material is used only where structurally necessary, while thinner material is used in areas with lower load requirements, minimizing overall weight while maintaining sufficient strength.

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

The design achieves a significant weight reduction while maintaining structural integrity, eliminating the need for additional surface treatments, and simplifying the production process.

Implementation Method 1

The first wall element is connected to the support structure by means of a spot weld

Methodology Applied
Scientific EffectWelding: Welding

Implementation Method 2

the second wall element is connected to the support structure by means of a second laser weld

Methodology Applied
Scientific EffectLaser welding: Laser Beam Welding

Data Source

PatentEP4530147A1Side wall for a body of a rail vehicle and method for producing the side wall
Publication Date: 2025.04.02 SIEMENS MOBILITY GMBH
  • EP4530147A1 patent drawingFigure 1
  • EP4530147A1 patent drawingFigure 2
  • EP4530147A1 patent drawingFigure 3A

AI summary

The invention relates to a side wall (40) of a car body and a method for manufacturing the side wall (40), wherein the side wall (40) has a support structure (70) and at least one outer wall (65) with at least one first wall element (80) and a second wall element (85) adjoining the first wall element (80), wherein the first wall element (80) is connected to the support structure (70) by means of a spot weld (160) and the second wall element (85) is connected to the support structure (70) by means of a second laser weld (162).