Example: Implementation of New Operational Availability Model into Toyota USA

We have applied for new operational availability model into Toyota in U.S.A. (Toyota USA) with a 4 step system as shown in Fig. 5.


Figure 5. Model to link impact of multiple Steps

Inherited Impact of Step 2=\(\frac{\text { ST2 }}{\text { ST2+WT2+ET2 }} \times \frac{S T 3}{S T 3+W T 3+E T 3} \times S T 4\)

Where \(ST2\) is Short time to Step 2 from previous steps.

\(WT2\) is work delay at Step 2

\(ET2\) is equipment downtime at Step 2

\(ST2\) is Short time to Step 3 from Step 2

Introduced Impact of Station 2=\(\frac{W T 2+E T 2}{S T 2+W T 2+E T 2} \times \frac{W T 3+E T 3}{S T 3+W T 3+E T 3} \times S T 4\)

Inherited Impact of Step 1= \(\frac{S T 1}{S T 1+W T 1+E T 1} \times \frac{S T 2}{S T 2+W T 2+E T 2} \times \frac{S T 3}{S T 3+W T 3+E T 3} \times S T 4\)

Where \(S T 1\) is Short time to Step 1 from previous steps.

\(W T 1\) is work delay at Step 1

\(E T 1\) is equipment downtime at Step 1

\(S T 1\) is Short time to Step 2 from Step 1

Introduced Impact of Station \(1=\frac{W T 1+E T 1}{S T 1+W T 1+E T 1} \times \frac{S T 2}{S T 2+W T 2+E T 2} \times \frac{S T 3}{S T 3+W T 3+E T 3} \times S T 4\)

\(E S=\frac{\frac{\frac{E T 1}{S T 1+W T 1+E T 1} \times S T 2+E T 2}{S T 2+W T 2+E T 2} \times S T 3+E T 3}{S T 3+W T 3+E T 3} \times S T 4+E T 4\)

\(E s\) is the overall equipment impact to the system shown in Fig.5.

\(E O A=\frac{\text { Production Time-Es }}{\text { Production Time }} \times 100 \%\)

\(E O A\) is the Equipment \(\mathrm{OA}\) of the overall system shown in Fig.5.

\(W O A=\frac{\text { Production Time-Ws }}{\text { Production Time }} \times 100 \%\)

\(WOA\) is the Work Delay \(OA\) of the overall system shown in Fig.5.