Cleaning of steel rods in a cleanroom

[murt100]

I am working on a project looking at improving a cleaning process for stainless steel rods being used in a cleanroom process.

Currently, the rods are used to support a PVC catheter that is dipped inside a cleanroom. The process leaves a solvent residue on the rods that must be cleaned off before they can be re-used.

At the moment, the rods are taken out of the cleanroom, cleaned with detergent in a hot water bath then dried and brought back in.

However, we would prefer to have a cleaning process which could be used in the cleanroom without the need to remove the rods.

Approximately 200 rods are cleaned at any one time, approx. 400mm in length x 2mm in diameter.

Any suggestions would be welcome. A quicker, non-immersion technique would be preferred.

 

[unclesyd]

What is the residue as your Op doesn't give anything to work with./
What are your concerns about immersion?

 

[cloa]

What is solvent cleaning off the stainless rods?

 

[murt100]

Solvent is ethanol, residue is a proprietary coating dissolved in ethanol.

At the moment, we are washing the rods in warm water with a detergent then rinsing.

Has anyone had experience of using a water bath in a cleanroom? Ultrasonic cleaning might be another option.

 

[IRstuff]

I'm unclear what's the issue, Water rinses have been used in wet semiconductor processing for decades. If everything is done under a hood with proper negative pressure relative to the plenum, there should be no problems.

Perhaps you need to expand and clarify what your concerns are.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[unclesyd]

I agree withIRstuff if water will work and you are capable of drying the rods this is the best approach.
Depending on how the residue behaves with pure water you may have a once through or a two step cleaning process. Another approach is to add a cleaner like DeContam to the Immersion or Ultrasonic Bath.
Though not normally used for clean room applications you may want to look at the Vapor Degreasing Solvent, Vertrel, and Bromothane for solvent cleaning.

http://www.espimetals.com/index.php/online-catalog/359-decontam

http://www2.dupont.com/Vertrel/en_US/products/index.html

http://bromothane.com/Bromo_Products.html

 

[IRstuff]

There are lots of solvents that are used in and compatible with cleanrooms. I guess one question is what does "cleanroom" mean in your context. My experience was with Class 100 cleanrooms used for semiconductor manufacturing. We used:
> Triton X-100 surfactant
> Acids galore, HF, HCL, HNO3, etc.
> Solvents galore, acetone, methanol, MEK, TCE, etc.

Reagent grade chemicals are compatible with those levels of cleanliness, and the rest is instantiated within a cleanhood.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize