Millipore Testing – Gravimetric

Millipore testing is all about evaluating cleanliness based on the presence of particles or other solid, non-soluble contaminants.  In general, it can not be used to detect the presence of hydrocarbons or other contaminants which will be solubilized in the extraction process.  The results of Millipore testing are generally expressed by weight using gravimetric analysis …

Millipore Specifications Update – Extraction and Sample Preparation

“Millipore” testing evaluates cleanliness by extracting particulate contamination from a surface and then either weighing or counting and quantifying the collected particles to assess the cleanliness achieved by a prior cleaning means.  The first step in either case is to collect and prepare for analysis any particulate residue remaining on the surface after pervious cleaning.  …

Foil Test – Foil Variabilities

It would make sense that variations in the aluminum foil used for testing in the foil test for ultrasonic performance could have a bearing on the outcome of the test.  Most people use standard “grocery store” aluminum foil for testing because it is inexpensive and widely available.  So let’s talk about that first.  The most …

Millipore Testing – Help!

I just spent a couple of hours re-reading several of the ISO specifications related to “Millipore” testing including ISO16232-3 and -7.   I put the word Millipore in quotes here because although these are normally called Millipore specifications, none of them mentions the word Millipore.  (Millipore happens to be the name of a company that developed …

Aluminum Foil Test – Foil Perforation Mechanism

Until recently, I was only able to theorize about the mechanism involved in the perforation of aluminum foil by ultrasonic cavitation.  I no longer have to theorize! My theory had always been that perforation of aluminum foil was due to the repeated flexing of aluminum foil as cavitation implosions occurring on opposite sides of the foil …

Aluminum Foil Test

If you’ve heard of ultrasonic cleaning you’ve probably heard of the aluminum foil test.  The practice of putting a piece of aluminum foil into an ultrasonically activated tank of water probably began as a novelty demonstration.  The holes produced in the aluminum foil by the collapse of cavitation bubbles at least showed that something interesting …

Hot Air Drying – Tips and Pitfalls

Drying is the last and often a critical part of a cleaning process.  In many cases it is also the most time and energy consuming.  It is often the most difficult part of the process to specify and control.  Although there are several drying technologies available, blowing with hot air is simple and by far …

Stainless Steel Compatibility

With its well-deserved credentials for chemical resistance and durability, stainless steel and particularly 316 grade stainless steel is a “go to” for the fabrication of ultrasonic cleaning tanks.  Although it performs well in most applications, there are still those where stainless steel has its limitations.  Stainless steel achieves its “stainless” characteristic by developing a very …

Wash, Rinse and Dry

Today’s industrial parts cleaning processes commonly employ at least three distinct steps. The basic steps are Washing, Rinsing, and Drying. Each step is custom tailored to the overall requirement with the range of options for each much broader than one not intimately involved with the technology might imagine. In some processes, in fact, it is …