7/27/2019 Rolled Throughput Yield (Training)

1/7

The hidden factory

7/27/2019 Rolled Throughput Yield (Training)

2/7

RTY is the probability (%) that a single unit can pass througha series of process steps free of defects

It is used to assess the true yield of a given process , withadditional consideration given to rework and scrap

RTY exposes what is often called the hidden side of thefactory that plagues so many organizations and (sadly) is

sucking profit right off their financial statements

It is one of the most powerful operational metrics anorganization can use to monitor its performance

7/27/2019 Rolled Throughput Yield (Training)

3/7

First Pass Yield (FPY) simply calculates the # of good unitsproduced / by the # of total units going into a process step,or

FPY = Good Units / Total Units

Rolled Throughput Yield (RTY) adds the consideration of rework and scrap and multiplies the yields from each

process step, or

RTY = (FPY1) (FPY2) (FPY3)

7/27/2019 Rolled Throughput Yield (Training)

4/7

PROCESS #1 100 parts went through this process and 84good parts left this process (16 were scrapped)

First Pass Yield (FPY): 84%

PROCESS #2 With some WIP laying around, 110 partswent through this process with 82 good parts passing (10were scrapped and 18 were reworked)

First Pass Yield (FPY): 74.54%

PROCESS #3 With even more WIP laying around thisprocess, 138 parts were produced with 126 parts passing (12were scrapped)

First Pass Yield (FPY): 91.30%

7/27/2019 Rolled Throughput Yield (Training)

5/7

7/27/2019 Rolled Throughput Yield (Training)

6/7

LETS RECAP:

PROCESS #1 = 84 / 100 parts and FPY of 84%PROCESS #2 = 82 / 110 parts and FPY of 74.54%

PROCESS #3 = 126 / 138 parts and FPY of 91.30%

SO:

RTY = (FPY1

) (FPY2

) (FPY3

)

WHEN CALCULATED:

RTY = (.84)(.7454)(.913) =57.16%

7/27/2019 Rolled Throughput Yield (Training)

7/7

This value (57.16%) is a more accurate representation of how this production line is performing, and takes intoaccount the rework and scrap from all process steps

More importantly, this value is our opportunity as leanand six sigma practitioners to identify the true root causesof problems and fix them permanently

We must not kid ourselves into believing we areperforming better than we actually are

By focusing on RTY, we can be sure we stay focused on

the true pulse of the organization