Breakdowns Happen: Factoring Downtime Into Your Simulation
- 1. Breakdowns Happen: How to Factor Downtime into your Simulation Simulation expert Brian Harrington explains the key learning points simulation modelers should consider when working with downtime.
- 2. Introductions Brian Harrington, CSSBB - 20 years in simulation at Ford Motor Company - Experienced Six Sigma Blackbelt and SIMUL8 Manufacturing Consultant - Director of MTN-SIM, a simulation specialist consulting firm SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 3. MTBF & MTTR 1. How often does a machine fail (MTBF)? 2. How long does it take to repair it (MTTR)? These two questions may seem simple, however are often abstracted within the forest of machinery and clouded by human behavior. SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 4. One of the most debatable pieces of data that goes into a simulation is the stochastic behavior of machine downtime. • • • • • • • • • • • Introducing new equipment Collecting downtime data Summarizing downtime data Catastrophic downtimes Lock-out procedures Time to react, travel, and repair Distributions to represent downtimes Limited skilled trades Simultaneous faults Protective capacity Equations (MTBF, MTTF, MTBC, MTTR, etc…) Plants perspective Designer’s perspective SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 5. Availability SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 6. SIMUL8 Efficiency… Prove it MTBF Availability MTTR Efficiency Go to MTBF MTTR Defined.S8 SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com 6
- 7. Capture downtime at station or line level? SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 8. Math behind the Spreadsheet SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 9. Equivalent Results SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 10. Advantages of Aggregate Values • Used for predicting station/cell level downtime based on components • Reduces large data files • Ease of communicating downtime figures • Aligned with scope of model SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 11. Distributions for MTBF & MTTR? Exponential Erlang SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 12. Stat::Fit (View your data!) • • • Data tables (Input data) Input Graph Descriptive Statistics • • Auto::Fit Distribution Viewer SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com Go to View Dist.S8
- 13. Time to React & Travel? Named Distributions and the Combination Distribution can capture some of this behavior. SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 14. Lock-out Procedure A safety protocol which protects skilled trades when entering a station or work cell. Each skilled trade will have a named-lock, which will be “locked” on an electrical panel before entering a work cell for a repair. The protocol will have several required steps to assure that all power is off, assuring no machinery, robot, etc. movement. A typical lock-out procedure might take 3 to 7 minutes to complete! SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 15. How do we account for the Lockout Procedure? A lockout procedure might be assumed to be followed on the lengthier repairs such as repair times that take 10 minutes or more. SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 16. VL for creating a Bimodal Distribution SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 17. Skilled Trades on Repairs SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 18. TimeView Improve Performance Downtimes cause Performance issues! (Wait & Blocks) SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 19. Design Facilities to Absorb Downtime • Protective Capacity – Resides in an over-speed (Push) – Resides in buffers – Preventative maintenance – Skilled trades available – Material handling systems • Power & Free • Electric Monorail Systems • Power Friction SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
- 20. Questions SIMUL8 Corporation | SIMUL8.com | info@SIMUL8.com
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