Tolerance and Stack Analysis

Manual and Advance approach

Author

Waqas Amjad

S167777

Supervisor

Prof. Stefano Tornincasa

DIGEP -Dipartimento di Ingegneria Gestionale e della Produzione

I FACOLTA' DI INGEGNERIA

DEPARTMENT OF MECHANICAL ENGINEERING

September 2012

TOLERANCE & STACKUP ANALYSIS

MANUAL AND ADVANCE APPROACH

Waqas Amjad

TITLE OF THESIS:

PROF. STEFANO TORNINCASA DIGEP -DIPARTIMENTO DI INGEGNERIA GESTIONALE E DELLA

PRODUZIONE I FACOLTA' DI INGEGNERIA

Waqas Amjad

SUPERVISOR

Thesis Orientation

Introduction & Objective

Manual Approach

Advance Approach CAT systems

CAT system Characteristics

CASE STUDY

Thesis Orientation

Introduction & Objective Manual Approach

Advance Approach CAT systems

CAT system Characteristics

CASE STUDY

PRODUCTION PROCESS

CONCEPTUAL

DESIGN

DETAILED

DESIGN

EMBEDED

DESIGN

TOLERANCING

PROCESS

Introduction

TOLERANCING PROCESS

TOL.

SPECIFICATION

TOLERANCE

SYNTHESIS

TOL.

ANALYSIS

TOLERANCE

VERIFICATION

Introduction

Statement of the Problem

Whether A Collection Of

Parts Would Fit Together

Before They Were

Manufactured????

By performing

Tolerance analysis &

Tolerance stackups

Part1:

Manual Models for Stackup Analysis

Part 2:

Search of CAT systems

Part 3:

Compare Characteristics

Objective

Thesis Orientation

Introduction & Objective

Manual Approach Advance Approach CAT systems

CAT system Characteristics

CASE STUDY

Manual Approach

Setup Datums

Schematics for blueprint dimension

Prepare Tolerance Chart

Balance dimensions & Mean dimensions

Mathematical Models for Stackup Analysis

Case Study

Setup Datums

Schematics for blueprint dimension

Prepare Tolerance Chart

Models for Stackup Assemblies

"+" Tolerance "-" Tolerance ± Tolerance RMS

A B C D E

1 15 0.5 0.25

2 15 0.5 0.25

3 20 0.5 0.25

4 25 0.5 0.25

5 10 0.5 0.25

6 100

100 85 2.5 Total 1.25

Nominal Value 15

Max Gap 17.5

Min Gap 12.5

RSS Max 16.25

RSS Min 13.75

Case Study Manual Results

Thesis Orientation

Introduction & Objective

Manual Approach

Advance Approach CAT systems CAT system Characteristics

CASE STUDY

Advance Approach using Current status of CAT systems

SIGMUND WORKS

SolidWorks Integration

SIGMUND ABA

DCS

DCS-Datum Flow Chain

CETOL 6

GD&T Advisor

TolAnalyst

TolMate

Vis VSA

And many more

Case Study SolidWorks Results

Study Name Study1

Analysis Parameters

Orientation tolerances ON

Normal to origin feature YES

Float fasteners and pins ON

TolAnalyst Measurement (mm)

Nominal Value 15

Minimum Value 12.5

Maximum Value 17.5

RSS Minimum 14.038

RSS Maximum 15.957

Conclusion of Case Study

SolidWorks

Nominal Value=15

Minimum Value=12.5

Maximum Value=17.5

RSS Minimum=14.038

RSS Maximum=15.957

Manual Calculation

Nominal Value=15

Minimum Value=12.5

Maximum Value=17.5

RSS Minimum=13.75

RSS Maximum=16.25

There is difference in calculation due to the effect of max-min contributors which effect the stackup tolerance and Assembly constrains assumed which have major role in defining the checks on Assembly floor.

NEW WORK

QUESTIONS?