Overall Equipment Effectiveness (OEE)

•  What is overall equipment effectiveness(OEE)?

        Overall Equipment Effectiveness (OEE) is a measure comparing how well manufacturing equipment is running compared to the ideal plant.

 

• The Goals of OEE

  •  zero breakdowns
  • zero abnormalities 
  •  zero defects   
  • zero accidents
  • Awareness of the losses.
    
     
    

    •    OEE Factors 

                     The overall performance of a single piece of equipment or even an entire factory, OEE is a percentage derived by multiplication of the three ratios.

    OEE = Availability x Performance Rate x Quality Rate

     

                            The availability rate

           The availability rate is the time the equipment is really running, versus the time it could have been running.

                                  The performance

           To perform a defined task in terms of his or her work-pace as long as working condition are correct.

                                    The quality rate

        The quality rate is the amount of good products versus the total amount of products produced.

     

    The availability

    Availability (Average per day) =

     

     

     

    The performance rate

    
    

                         Performance Rate=

     

     

      The quality rate

                           Quality Rate=

      

                 OEE Factors and Losses

     
     

                          Downtime            

                 Downtime refers to time when the machine should be running, but it stands still. Downtime includes two main types of loss:

     

    1. Equipment Failures

    • Sudden and unexpected equipment failures.
    • Breakdowns.
    • Machine is not producing any output.
     

        2. Setup and Adjustments

          Most machine changeovers require some period of shutdown so I that internal tools can be exchanged. The time between the end of j production of the last good part and the end of production of the  next good part is downtime.

                    Speed Losses
    

       A speed loss means that the equipment is running, but it is not running at its maximum designed speed. Speed losses include two main types of loss:

        1.Idling and Minor Stoppages

    When a machine is not running smoothly and it will lose speed and obstruct a smooth flow.

    The idling and stoppages in this case are caused not by technical failures, but by small problems such as parts that block sensors or get caught in chutes.

    2. Reduced Speed Operation

    Reduced speed operation refers to the difference between the actual operating speed and the equipment's designed speed (also referred to as nameplate capacity).

                             Deffect Losses

    A defect loss means that the equipment is producing products that do not fully meet the specified quality characteristics. Defect losses include two major types of loss:

     

                      1. Scrap and Rework

    Loss occurs when products do not meet quality specifications, even if they can be reworked to correct the problem. The goal should be zero defects, to make the product right the first time and every time.

     

                        2. Startup Losses

    Startup losses are yield losses that occur when production is not I immediately stable at equipment startup, so the first products do I not meet specifications.

                              Benefits of OEE

    • Directly tie production efficiencies to fiscal reporting
    • Reduce investigation time for root cause analysis
    • Decrease costs through waste elimination
    • Increase customer satisfaction through quality improvement.
     
    

                          How to help OEE

  • • Unnecessary equipment breakdown.
    • Downtime due to setup and adjustment.
    • ldling and minor stoppages due to rack of raw materials to process due to bottlenecks or poor production planning.   
    • Defects that require reprocessing.
                              How to Improve OEE
  • 
    teach the operator about the equipment.
    focus the operator's attention on the losses'
    grow a feeling of ownership of the equipment.
    Using TPM method.
    Using Fishbone Diagram.