Ultrasonics – Effect of Frequency Removing Particles

A previous blog revealed that ultrasonic frequency has an effect on the removal of soluble contaminants.  In general, lower frequency will be more effective in the removal of soluble contaminants.  Today’s blog will discuss the effect of frequency on the removal of insoluble contaminants – ie. particles. As ultrasonic frequency is increased, two things happen.  First, the …

Ultrasonics – Effect of Frequency Removing Soluble Contaminants

Earlier blogs have explained the effect of frequency on the size of cavitation bubbles and where they are formed.  Today’s will explain the effect of bubble size and location on removing soluble contaminants. Soluble Contaminants – The removal of soluble contaminants requires that solvent saturated with the contaminant being removed must be displaced from the solvent/contaminant …

Ultrasonic Cleaning – Removing Particles

In a previous post, Ultrasonic Cleaning – Soluble Contaminants, I discussed the effect that ultrasonic cavitation and implosion play in enhancing the removal of soluble contaminants from surfaces.  Today’s blog will introduce the effect that ultrasonic cavitation and implosion have on the removal of insoluble particles from surfaces.  There are several mechanisms that can cause …

Reader Question – Ultrasonics – “Near Field”

A reader has asked for a description of how “near field” ultrasonics works.  First of all, the term “near field” is one that is not well defined in the ultrasonic cleaning world.  It appears to well defined and have major significance in non-destructive testing using ultrasonics as indicated in these links  www.signal-processing.com and  www.ndt-ed.org, but there is …

Ultrasonics – Monitoring Ultrasonic Performance

In the blog “Reader Questions – Monitoring Ultrasonic Transducers,” I suggested a couple of ways one might test individual ultrasonic transducers to assure they have not become ineffective due to de-bonding from the cleaning tank.  In an extension of the spirit of that blog, quality control measures for ultrasonic cleaning performance, I decided to check out a paper I …

Cleaning – Insoluble Contaminants – Particles

A previous blog Cleaning – Soluble Contaminants – “Solvents” described soluble contaminants as those contaminants that can be dissolved using a solvent or engineered liquid such as a surfactant.  Contaminants that are not soluble are the other distinct classification of contaminants.  Sometimes the line between soluble and insoluble is not well defined since there are …

Reader Questions – Monitoring Ultrasonic Transducers

Today’s blog is responding to two questions asked by readers.   Both concern monitoring of ultrasonic transducer performance. Ralph Clendenin asks – “Is there a measurement of the frequency I need to be aware of during “good” operation I can check monthly that would show reduction in cleaning due to change in frequency?” Stephen Sharkey asks – …

Cleaning – Soluble Contaminants – “Solvents”

In the blog entitled The Lowdown on Dirt, the three basic classes of contaminants were described.  They are – soluble, particulate and a mixture of soluble and particulate.  There are, of course many hybrids and permutations but for purposes of discussing the ultrasonic effect on cleaning we’ll limit to these three for now.  Later on we can …

Is It Clean – Particles – Particle Generating Substrates

Some substrate materials are inherent particle generators and may never be cleaned to the point of there being no particles present.  With these materials, particles are a way of life and can not be avoided.  This, of course, makes cleanliness testing using particle analysis a difficult if not impossible task.  The difficulty is exacerbated by …