Transcript fr_a4.ppt

Term Project Presentation:
Design and Analysis of a Turbine
Blade Manufacturing Cell
MEAE-6960H01
Professor Ernesto Gutierrez-Miravete
Presenter: Ray Surace
Project Overview :
•Created a hybrid coding scheme for three turbine blade part numbers
(P/N) to be produced in a group technology environment
•Reviewed the performance of an initial turbine blade cell design with 12
workstations
•Developed an improved cell design with 10 workstations
•Created a facility layout using the Column-Sum Insertion Heuristic
•Used a modified Approximate Three-Stage Markov Chain Model to
determine the optimum size of buffers placed before and after an airfoil
overlay coater
•Performed a Mean Value Analysis to validate the final design of a turbine
blade manufacturing cell
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Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
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Part Coding:
•Three (3) P/Ns with common features were grouped to form a composite part family:
P/N
100b1
200b1
100b2
Description
Engine Model 100 STG 1 Turbine Blade
Engine Model 200 STG 1 Turbine Blade
Engine Model 100 STG 2 Turbine Blade
•An alphanumeric hybrid coding scheme was derived from the machining sequence:
P/N
100b1
200b1
100b2
Code
1b1y3
2b1y1
1b2n0
•The code makes use of the chain property; each character place in the code has a
specific meaning:
Example: P/N 100b1
Code: 1
b
first digit
of engine model
1
y
part stage
i.e. 1=STG1
part type
b=blade
3
cooling hole
code
coating?
y=yes, n=no
•Cooling hole code: 0=no cooling holes, 1=laser cooling holes, 2=EDM cooling holes,
3=laser and EDM cooling holes
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Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
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Performance of 12 Workstation Cell Design :
•Initial cell design incorporated 12 workstations into a ‘U-shaped” cell layout to complete machining and
finishing operations on P/N 100b1, 200b1, and 100b2 turbine blade castings .
Machine Number
1
2
3
4
5
1
2
3
4
5 6
6
7
isle
12
11
10
9
8
7
8
9
10
11
12
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Description /
Operation
Grinder /
Attachment Grind
Grinder / Root and
Tip Grind
CMM / Grind
Inspection
Laser Driller /
Laser Cooling
Holes
EDM Machine /
EDM Cooling
Holes
Coater / Airfoil
Coating
Argon Purged
Furnace / Heat
Treat
Peen Machine /
Attachment Shot
Peen
X-Ray Machine /
X-Ray Inspection
Water-flow Bench /
Blocked Hole &
FM Inspection
Air-flow Bench /
Air-flow Inspection
Inspection Station /
Final Inspection
Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
100b1 Operation
Sequence
1
200b1 Operation
Sequence
1
100b2 Operation
Sequence
1
2
2
2
3
3
3
4
4
-
5
-
-
6
5
-
7
6
4
8
7
5
9
8
-
10
9
-
11
10
-
12
11
6
4
Performance of 12 Workstation Cell Design :
•Customer demand rates for all 3 P/Ns dictate that 9.12 parts must be produced per hour
•Thus, cycle time C, must be 0.11 hrs. for each workstation
•Processing time of the precipitation heat treat furnace is 24 hours; the retort can hold 150
blades.
Thus, C = 0.16. This is unacceptable.
•To meet customer demand rates the furnace retort must have a capacity of
X
24hours
 218.18 parts
.11hours
part
•Checking utilization we find that the heat treat furnace is a bottleneck operation:
Um 
p
im
i
Pm
Di
Thus, Um, furnace= 1.46
•If a furnace with a capacity of 219 blades is purchased, WIP would increase by 69 pcs:
219 blades - 150 blades = 69 blades
•By removing the heat treat furnace from the cell, the overall WIP (WIP=PxT) of the cell
can be reduced by 150 pcs. :
New cell design to include 10 workstations; precipitation heat treat and shot peen
machines moved to a separate department
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Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
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Layout of 10 Workstation Cell Design :
•Final turbine blade manufacturing cell design incorporates 10 workstations into a ‘U-shaped” cell layout:
Machine
Number
1
2
3
4
coater input buffer
5
5
4
3
2
1
6
7
6
coater output
buffer
7
8
9
8
10
isle
9
10
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Description /
Operation
Grinder /
Attachment
Grind
Grinder / Root
and Tip Grind
CMM / Grind
Inspection
Laser Driller /
Laser Cooling
Holes
EDM Machine /
EDM Cooling
Holes
Coater / Airfoil
Coating
X-Ray Machine
/ X-Ray
Inspection
Water-flow
Bench / Blocked
Hole & FM
Inspection
Air-flow Bench
/ Air-flow
Inspection
Inspection
Station / Cell
Inspection
Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
100b1 Operation
Sequence
1
200b1 Operation
Sequence
1
100b2 Operation
Sequence
1
2
2
2
3
3
3
4
4
-
5
-
-
6
5
-
7
6
-
8
7
-
9
8
-
10
9
4
6
Turbine Airfoil Manufacturing Facility Layout :
•Column Sum-Insertion heuristic used to create a block plan of a turbine airfoil manufacturing
facility with the following departments:
–Receiving
–Vendor Inspection (incoming casting inspection)
–Blade Cell
–Vane Cell
–Heat Treat / Sot Peen Department
–Shipping
Receiving
A
Vendor Inspect
Receiving
I
A
Blade Cell
I
E
U
Vane Cell
U
A
Blade Cell
Vendor Insp.
X
A
Heat Treat/Peen
Shipping
E
O
O
O
Heat Treat / Peen
Vane Cell
A
Shipping
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Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
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Analysis of Coater Buffer Capacity :
•Buffers are required before and after the coater in order to maintain a cycle time of 0.11 hrs.
•An Approximate Three-Stage Markov Chain Model was modified to determine the optimum
buffer size
•The following modeling assumptions were made:
–Cell modeled as a paced transfer line with M=10 stages
–Coater capacity of 19 blades
–Assumed the average mean time to failure, α-1 of workstations 1-5 and 7-10 approaches 0.
Therefore α1-5,7-10 = 1e-6
–Assumed αcoater=1. Once the coater starts a cycle, any incoming parts go into the incoming buffers
–The avg. mean “repair” time (coater cycle time) for the coater b-1=18.18cycles, or b=0.05
•The results of the Three-Stage model analysis are as follows:
–The effectiveness of the cell without buffers, E00=.53282
–The maximum cell effectiveness is E21=.53284
–Therefore, the optimum buffer size before and after coating is Z=21
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Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
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Performance of 10 Workstation Cell Design:
•A Mean Value Analysis (MVA) was performed to validate the 10 workstation blade cell design
•The cell was modeled as a closed network with single servers
•It was assumed that each P/N (p) may visit each workstation (j) in that part’s processing sequence
once
•A visit count (Vjp) table was constructed:
Machine #
1
2
3
4
5
6
7
8
9
10
100b1
1
1
1
1
1
1
1
1
1
1
200b1
1
1
1
1
0
1
1
1
1
1
100b2
1
1
1
0
0
0
0
0
0
1
• To initialize the algorithm, a queue length (Ljp) of 1 was assumed in front of each workstation
•The algorithm was calculated using the following formulas:
1
jp
W jp  u 
N p 1
Np
L jpu   L jr u
1
jp
r p
1
jr
(eqn. 11.24 A&S)
,
Xp 
•After three (3) iterations the algorithm converged
Np
M
V jpW jp
(eqn. 11.26 A&S)
,
L jp  X p V jpW jp 
(eqn. 11.27 A&S)
j 1
*The total production rate of the cell, Xtotal=9.92 parts per hour. This exceeds the
demand, 9.12 parts per hour by 8%. Thus, the 10 workstation cell design is acceptable.
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Design & Analysis of a Turbine
Blade Manufacturing Cell Ray
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