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​Hi,

I am reliability engineer in Railway industry.

I would like to have your help to understand / find a relationship between 4 parameters: reliability, availability, maintainability and performance in the transportation industry.

 It is standard recognized the relation between reliability, availability and maintainability with the formula:

A = MTBF / (MTBF + MTTR) or

A = Uptime / (Uptime + Down time)

A = availability

MTBF represents the parameter for reliability, MTBF = Int R (t)

MTTR stands for maintainability

In industry, it is recognized, understood and widely use the Overall Equipment Effectiveness (OEE). Calculation process of OEE is well established. This OEE parameter links performance, availability, and quality.

OEE = Availability x Performance x Quality

 In the transport field is focus on performance or delay.

Often is given by "Service Reliability Standard of 99.50% on-time performance (SROTP)"

I found, SROTP = (Trips completed) / (Trips scheduled)

Please, could someone answer to my questions:

Can (SROTP) be interpreted differently?

How could we translate performance in terms of availability or reliability in the transport field?

How does connect practically SROTP with Availability?

I wonder if there is some equivalent of the OEE in transportation?

 Any answer will be great appreciate.

 Thank

Victor Iliescu

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VICTOR ILIESCU
RELIABILITY ENGINEER (RAMS)
PRATT & WHITNEY CANADA
LONGUEUIL QC
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Dear Mr. Victor,
May i suggest my Book " RAMS and LCC for railway industry: analysis Modeling and Optimization.
You can find it at amazon.
ECC also offer online training. Please check in the link below.
https://www.eduardocalixto.com/online-training/online-training-for-railway/
Let´s keep in touch.
Best regards,
Eduardo Calixto


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Eduardo Calixto Founder & CEO
Asset Management And RAMS Expert
Ulm
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OEE = Availability x Performance x Quality

Availability = A/B x 100

Performance = C/A x 100

Quality = D/C x 100

 

NB:

"A,B,C & D are used just for illustration, these parameters are determined by what the formula is used for"

 

So in your case, A = uptime and this should be the denominator for calculating performance.

The SROTP formula you gave (Trips completed/Trips scheduled) is analogous to

Performance = C/A x 100

So "trips scheduled" = Uptime.

​

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Augustine Amoako-Awuah
Tema GA
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