Reliability Testing Protocol on a new Peristaltic Pump

[Steve Prevette]

I am planning on running accelerated life cycle test with three different variables, temp, RH, speed of the pump. Is there any equation for this to calculate acceleration factor ...

Also I m planning to keep the pumps in chambers (accelerated temp 50c, 85%RH) for x hrs then take the pumps out of chamber and run the pumps for x hrs at room temp at max speed (observed in the field).... Is this the right approach or should I run the pumps while hey are in chamber ? I

Without actually running tests at different values of the variables and determining the effect of the variable on life, I don't believe there are any standafd "acceleration factors". Perhaps heat actually has no effect on the unit. You will only learn that through testing the unit, or some form of FMEA on individual components and how they interact in the design.

It seems to be (as an engineer) that the pumps should be run in the chamber if you want to find out the affect of the environmental factors. If these are long lived units (on the order of at least days even in the "extreme" conditions), the pump will have returned to "normal" environmental levels pretty quickly in the test.

 

[Miner]

I am planning on running accelerated life cycle test with three different variables, temp, RH, speed of the pump. Is there any equation for this to calculate acceleration factor ...

Also I m planning to keep the pumps in chambers (accelerated temp 50c, 85%RH) for x hrs then take the pumps out of chamber and run the pumps for x hrs at room temp at max speed (observed in the field).... Is this the right approach or should I run the pumps while hey are in chamber ? I

A lot depends on the failure mechanisms at play. Sometimes the storage conditions have a greater and more damaging impact on a product that the actual operating conditions. However, in most situations it is the operating conditions that will wear out a product.

For a pump, I would expect that you should run it in the chamber.

You would typically calculate an acceleration factor for each stressor individually then use them as shown: AF1 * AF2 * AF3 * ...

 

[jakson22]

ust run several items on the test bench in parallel and assume exponential as good enough, and give failure rate as total failures seen (not every item has to run to failure) divided by the total unit runtime. So if I run 5 units for a year (with replacement of failures) and have 3 failures, I assume this is the equivalent


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asad

 

[Steve Prevette]

ust run several items on the test bench in parallel and assume exponential as good enough, and give failure rate as total failures seen (not every item has to run to failure) divided by the total unit runtime. So if I run 5 units for a year (with replacement of failures) and have 3 failures, I assume this is the equivalent


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asad

Looks like your post got a little chopped up. Yes, if you run 5 units for a year and assume exponential behavior, then could be up to 5 unit-years of run time. If there were 3 failures (and assuming you did not replace the failed unit with a replacement to complete the year) your failure rate would be estimated as 3 divided by the total run time on the 5 units.

OR if you did replace each unit as it failed, and got a total of 5 unit-years of run time, failure rate would be estimated as 3 failures divided by 5 years or 0.6failures per year.

 

[ssuchak]

Hi Have you done the reliability testing for the peristaltic pumps.
can you share the protocols and the methods you followed for the same.

Thanks in advance
Shyam