Analysis Process in Mobile Crane Development

Andreas Hofmann - November 2011

FAUN-HTC2011 1

Overview

Circumstances

Analysis Process Before

Analysis Process Today

Preview

FAUN-HTC2011 2

Circumstances

Analysis Boundaries

FAUN-HTC2011 3

• Approx. 40 main boom telescoping states

• Approx. 20 possible configurations per state

• Over a turning range of 360°

• Additional boom extensions (~ 30-50 possible configurations)

• Different counterweights and outrigger bases

• And so on ….

More than 150.000 load cases to find a optimum that leads into a rated load value for the end customer

Analysis Process

Before (Design Driven)

FAUN-HTC2011 4

Design

Draft

Design

Concept Design

Structure Analysis

Drawing In Out

• FEM Analysis only as a proof of design

• Early stage design failures come to light too late

• Structural needs were “less important”

• Where analysis results were needed, long waiting times occurred

Analysis Process

FAUN-HTC2011 5

IGES Format Snapshot

(solid) Shell Model

Before (Design Driven)

Analysis Process

Today (Crane Driven)

FAUN-HTC2011 6

Structure

Draft

Structure

Concept Structure

In Out Design

Draft

Design

Concept Design

Drawing

• Structure tells design how to look like in general, from the very beginning

• Designer and structural engineer understand each others needs much better

• Weight is most important structural design is important

• More but smaller analysis steps lead to faster results

Analysis Process

FAUN-HTC2011 7

CATIA product opened inside HM

Analysis Process

FAUN-HTC2011 8

Midsurfaces creation

Analysis Process

FAUN-HTC2011 9

Stiching (semi-automatic)

Analysis Process

FAUN-HTC2011 10

FE Model

Analysis Process

FAUN-HTC2011 11

Designer modifies CAD models much faster than a structural engineer could modify FE models

Direct CAD model usage inside of HM speeds up calculation and ensures usage of the actual state of design

General finding

Preview

What we have started …

FAUN-HTC2011 12

• Catia V5 integrated pre-analysis by the designer

• Structural optimization of existing machines (new motors & exhaust systems)

• Structural optimization during concept phase

Thank you

ありがとうございます

FAUN-HTC2011 13