Basics Chapter 8-10 Flashcards
MTTR
Mean time to repair
= Sum of time for repairs / no. of repairs (hr)
Average time to repair
Energy Value Stream Analysis - 4 Steps
- Theoretical analysis of optimal operating point
- Reduce resource demand via technical improvement
- Minimise resource consumption during stand-by
- Energy Recovery
TPM - 5 Advantages
- Safer Working Environment
- Lower Costs through less unplanned downtime
- Higher quality through less rework and lower scrap rate
- Higher Productivity through higher throughput
- Higher Motivation through involvement in CIP
TPM - 4 Pillars
- Autonomous Maintenance
- Planned Maintenance
- Education & Training
- Health and Safety
TPM - 5 HS improvement measures
- Accident prevention programs
- H&S tours and audits
- Noise and pollution safety equipment
- Monitoring of activities by executives
- Health Improvement programs for employees
MTBF
Mean Time Between Failures
MTBF = Operating Time / No. of Failures
Average time for the occurrence of a failure
OEE - Explanation and Formula
Overall Equipment Efficiency evaluates the effectiveness of an TPM
OEE = Availability * Performance Efficiency * Rate of Quality
OEE Graphical
- Available Prod. Time + External Losses
- Available Production Time = Gross operating time + Down Time Losses => Availability
- Gross Operating Time = Net Operating Time + Speed Losses => Performance
- Net Operating Time = Valuable Operating Time + Quality Losses => Quality
Process Capability Index
- Compares the output of a process to the specification limits.
- Forming the ratio of the spread between the process specifications (the specification “width”) to the spread of the process values, as measured by 6 process standard deviation units (the process “width”).
- A process where almost all the measurements fall inside the specification limits is a capable process.
Six Big Losses with OEE Loss Category
- Breakdowns => Down Time Loss
- Setup & Adjustment => Down Time Loss
- Small Stops => Speed Loss
- Reduced Speed => Speed Loss
- Startup Rejects => Quality Loss
- Production Rejects => Quality Loss
Availability Calculation
A = (Daily Working Time - Break Time - Setup - Breakdown) / (Working Time - Break Time)
Production Time Calculation
Daily working Time - Break - setup - breakdowns
Produced Pieces Calculation
= Production Time / Cycle Time
Performance Efficiency Calculation
= Actually Produced Pieces / Produced Pieces in Opt. Cycle Time = Actual Cycle Time / Optimum CT
Rate of Quality Calculation
Q = Good Pieces / Produced Pieces
