1. M6205 SYSTEM SIMULATION AND MODELLING TERM PROJECT
Productivity Improvement in Automated Manufacturing Cell for Die Casting
M6205 SYSTEM SIMULATION AND MODELLING
TERM PROJECT

2. PROBLEM Statement
XYZ company manufactures Aluminium compressor cover castings in an automated manufacturing cell.
Current cell has the capacity to produce 40 parts per hour with annual volume of 2,22,000 parts.
Customer requirement increased to 2,30,000 parts per annum.
Company decided to increase its production rate to meet the demand.
Analyze efficient and cost effective solution to increase the production rate.

3. CASTING PROCESS FLOW Metal Arrival Pouring Solidification Cooling
Decoring
Cutting
Inspection
Shipping

4. CURRENT SYSTEM
System Layout
Similar cell Model

5. Simulation Specification
Entity
Molten metal
Casting
Resources
Die 1
Die 2
Die 3
Die 4
Decoring machine
Cutting machine
Processes
Solidification
Cooling
Decoring
Cutting
Attributes
Entity type: Molten metal, Casting
Robot 1 pick time
Robot 2 pick time
Entity picture
Time IN
Transporters
Robot 1
Robot 2

6. Assumptions made for the model
Molten metal arrives every 60 mins with quantity 41 units.
Entities enters the system only if the queue in the furnace block is less than 61 units
All 4 dies run with predefined capacity schedule
Cooling station is considered as a holding station.
Rejection rate of the parts at inspection station is taken as 10%
Simulation runs for 25 days and 30 replications

7. i/p DATA ACQUISTION AND ANALYSIS
Knockout process time: NORM (20,1.50)
Number of data point: 25
Solidification process time: NORM (297,2.36)
Number of data points :20
Cutting process time: NORM (16.7,0.513)
Number of data points: 20

8. ARENA MODEL

9. ANIMATION – Arena model

10. Verification & validation
Parameters
Existing model
Units
Metal time between arrivals 60
mins
Metal arrival quantity 41
nos
Metal first creation
120
Furnace decision
NQ (Request 1. Queue) < 62
No of die 4
Holding Furnace
Solidification 1.WIP == 0 || Solidification 2.WIP == 0 || Solidification 3.WIP == 0 || Solidification 4.WIP == 0
Decide die to pour
Solidification 1.WIP == 0||
Solidification 2.WIP == 0||
Solidification 3.WIP == 0||
Solidification 4.WIP == 0
Solidification time
NORM (297,2.36)
secs
Knockout process delay
NORM (20,1.5)
Production time
18.5
hrs/day
Results of simulation trial:
Number of replication 30
Sample Mean (Production/month)
Sample standard deviation
33.598
95% confidence interval
Lower:17299
Upper:17446
The Average production output: 41.5 nos /Hr.
96.25% matches with existing scenario
Current model simulates the actual scenario

11. Experimentation 1. Forced Die Cooling 2. Addition of 5th die
3. Employing an operator
Additional die
To increase the productivity
Increases Robot utilization
Investment=20,00,000 INR /Die
An extra operator is employed.
Will decrease die preparation time
Increasing the total production time per day
Investment=3,00,000 INR /operator
To reduce solidification time by 60 secs
Will have a direct impact on productivity
Investment=6,00,000 INR /Die 11

12. Comparison of simulation results
Existing
Forced Die cooling
5th Die addition
Reduced die preparation
Number of replication 30
Sample Mean
(production/month)
Sample standard deviation
33.598
44.689
43.172
36.578
95% confidence interval
Lower:17299
Upper:17446
Lower:19360
Upper:19533
Lower:19557
Upper:19716
Lower:18719
Upper:18860
Does not meet the monthly requirement
*Required monthly production :19167

13. Return on investment calculation
No. of parts (Existing)
17378
nos/month
Models
Forced cooling
5th die addition
Units
No. of parts manufactured per month (modified)
19444
19639
Additional parts produced
2066
2261
Manufacturing Cost/part
₹ 59.00
INR/part
Selling Cost/part ₹
Profit/part
Additional profit
₹ 1,21,894.00
₹ 1,33,399.00
INR/month
Investment
₹ 24,00,000.00
₹ 20,00,000.00
INR
ROI ( months)
19.7
15.0
Months
ROI ( years)
1.64
1.25
Years
Lowest ROI “Best of the solutions”

14. Employing Additional operator
conclusion
Forced Die Cooling
By introducing forced die cooling,customer requirement is met to a certain extent.
ROI is greater than that of addition of 5th die solution.
Addition of 5th die
By adding an extra die increases the productivity.
On the other hand robot utilization and efficiency is increased.
When compared to other solutions ROI is minimal
Employing Additional operator
Employing an additional operator decreases the preparation time but the solution doesn’t meet the monthly requirement and customer objective