Machine Uptime, what should I expect?

[wakobav]

I have been given a project of improving the machine up-time in a sheet metal fabrication plant to 90%, don't all laugh at once! We have some new machines and some old machines, mainly Amada punch presses and press brakes.

What sort of figures has anyone else come up with for this or a similar industry?

Thanks!

 

[IRstuff]

Is that so unreasonable? 90% availability still means that any given machine is down 1 day every 10 days. That's a potentially prohibitive cost to a company.

There are military systems that specified for >98% availability. Our IT network is required to have availability of around 98% as well.

The key to that is the ability to diagnose the problem quickly and repair quickly. This might entail having all most plausible spares on-site. Additionally, this requires your diagnosis tools to provide an answer in less than a few minutes and the ability to perform the repair in less than a few hours, assuming availability of spares.

Availability defined as: MTBF/(MTBF+MTTR+MLDT), where:
MTBF --> mean time between failures
MTTR --> mean time to repair
MLDT --> mean logistical delay time (parts availability)

A high MTBF is obviously desirable, but you can see that MTTR and MLDT can eat your lunch if it's not well controlled. Let MTBF=600hr, MLDT=5day, MTTR=3hr, Avail=83%. If MLDT is reduced to 1day, Avail=95%

TTFN

 

[griffengm]

Wakobav,
Make sure you know the definition being used! Some places want to include set-up time in the 10% while others place it in the 90.
This is one of those terms that gets used by different disciplines to include different factors.

Griffy