Daimler ChryslerCar Transport Upgrade

Team #3John Barr

Aladrian CrowderHilary Goldman

Matt Reber

Background Information Daimler-Chrysler Newark

Assembly Plant Assembly Process: 3

phases of production Paint Shop: workings and

history Transport System:

difference from plant norm

Phosphate and E-coat Process

Accumulation Lines: unique conveyor system

Accumulation Lines Skids go into

holding pattern when production is down

5 accumulation lines, each 200 feet long

Motor driven chain with high rollers

Accumulation Line Video

Problem Definition Destructive nature of

friction and wear from accumulation chains has caused severe damage to skids used in paint shop. Worn skids must be replaced and system must be modified to decrease effects of friction and wear.

Other Effects to System Cast iron rollers

showing same wear pattern as skids.

Worn skids fall off rollers – leads to down time and lost money

Life of System Components

A new fleet of approximately 80 skids are going to replace the current model, after 6 years of use.

Drive motors for accumulation chains are being over-worked.

All 826 cast iron rollers and bearings are being replaced.

Mission Statement

To develop a concept and working design that will significantly decrease the wear experienced by the skids.

Wants/Metrics Wants

Cost Performance System

Compatibility

Metrics Price Wear Rate

Wear Model Primary material property affecting

wear rate is hardness. Wear rate is inversely related to

material hardness by Archard’s Equation:

V=volume, K=wear rate, F=force, L=sliding distance, H=hardness

H

FLKV

Concept Development Initial Brainstorming

Increase wear resistance Eliminate wear

Increase Wear Resistance Alter hardness of current material Add sacrificial wear material

Eliminate wear Break contact between skid and chain

Increase Wear Resistance Alter Hardness of Current Material

Flame or Induction Hardening Suitable for 1045 steel Other properties of material do not change Wear-resistant coating

Bottom of skid directly hardened

Increase Wear Resistance Addition of Sacrificial Wear Material

Plastics Good wear characteristics Easily machined

Metals Attach to skids quickly Used in similar applications in industry

Wear pad

Skid

Eliminate Wear

Break Contact Between Skid and Chain Mechanically lift skid off accumulation

chain Reduces power drawn by motor to

drive chain Change to system is localized

Concept Comparison Wear pads

Plastic Pad Fails due to PV limit Cost far greater than other concepts

Metal Pad Industrial norm Inverse effect on other components of system

Hardening Effects only a minimal depth Similar effects of metal wear pad

Lifter One time application requiring periodic maintenance More complicated solution

Concept Selection

Support for Skid Lifter

Eliminates wear on skids Increases life of accumulation

chain Saves energy Reduces drive motor work-load Has no effect on other system

components

Skid Lifter Components

Skid Lifter

Geometry Lifting Power Structural Design

Geometry Design of lifter

limited by space Must remain

contained in existing accumulation line area

Goal – minimize volume of lifter

Lifting Power Mechanical

Screw jack Hydraulic

Oil Large forces

Pneumatic Air Clean

Pneumatic Power Used extensively in paint shop Clean Low maintenance and reliable

Last for 1,000 miles of rod travel Seals need replaced once every two years Valves good for 1,000,000 cycles

Structural(mechanical?) Design Simple machines implemented to

provide lift Inclined plane and wheel Greater distance needed, but less energy

Down PositionUp Position

Structural Design

Basic design repeated every 10 feet

Space

To keep the accumulation area structurally sound, and the design of the lifter small, it was decided to be contained within area shown.

Skid Lifter Design Pneumatic cylinder will provide force Simple machines implemented to

provide lift Inclined plane and wheel

Video clip of lifter

TestingFrequency of Clearance Height

0

2

4

6

8

10

12

14

16

0.931 0.9519 0.9728 0.9937 1.0146 More

Clearance Height (in)

Scab Plate Strength Test

0

1000

2000

3000

4000

5000

6000

7000

0 5 10 15 20 25

Time (s)

Te

ns

ile

Lo

ad

(L

bf)

Wear Rate Vs Hardness

3. 96E+00

1. 88E+00

2. 38E+00

1. 34E+00

0

0. 5

1

1. 5

2

2. 5

3

3. 5

4

4. 5

180 380 300 533

Current Condtions Flame Hardening I nduction Hardening Sure Alloy Wear Bars

Har n dess C on dit ion

Gantt Chart

TBD

Handoff Plan

Complete design specifications Individual component design Sub-assembly design Assembly instructions

Controls and Safety Logic Company procedure

Questions