Design and Analysis of a Turbine Blade Manufacturing Cell

1. Term Project Presentation: Design and Analysis of a Turbine Blade Manufacturing Cell MEAE-6960H01 Professor Ernesto Gutierrez-Miravete Presenter: Ray Surace

2. 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 Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace

3. Part Coding: • Three (3) P/Ns with common features were grouped to form a composite part family: • An alphanumeric hybrid coding scheme was derived from the machining sequence: • 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 1 y 3 • first digit part stage cooling hole • of engine model i.e. 1=STG1 code • part type coating? • b=blade 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 Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace

4. 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. • 1 2 3 4 5 6 • isle 12 11 10 9 8 7 Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace

5. 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 • Checking utilization we find that the heat treat furnace is a bottleneck operation: • 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 cellcan be reduced by 150 pcs. : • New cell design to include 10 workstations; precipitation heat treat and shot peen machines moved to a separate department Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace

6. Layout of 10 Workstation Cell Design : • Final turbine blade manufacturing cell design incorporates 10 workstations into a ‘U-shaped” cell layout: • coater input buffer • 5 4 3 2 1 • 6 • coater output 7 8 9 10 • buffer isle Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace

7. 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 Receiving • Vendor Inspect I • A I Shipping Blade Cell Vendor Insp. • Blade Cell E X • U U E • Vane Cell A O • A O • Heat Treat/Peen O Heat Treat / Peen Vane Cell • A • Shipping Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace

8. 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 Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace

9. 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: • 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: • (eqn. 11.24 A&S) , (eqn. 11.26 A&S) , (eqn. 11.27 A&S) • After three (3) iterations the algorithm converged • 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. Design & Analysis of a Turbine Blade Manufacturing Cell Ray Surace