How to Safely Clean Fine Mesh Lab Sieves with an Ultrasonic Cleaner

Cross-contamination is a constant concern in all laboratory practices and can be addressed by strict operating procedures to assure equipment is thoroughly clean before use. Thorough cleaning of fine mesh lab sieves used in analytical, science and testing laboratories can be crucial in meeting GLP standards.

Lab sieves, because of their design, present special cleaning challenges to assure residues from prior screenings are completely removed from fine mesh screens.

Manually scrubbing the sieves is not a sure-fire means to clean them. A time-consuming operation in itself, the chief area of concern is potential contamination of subsequent products being processed because 100% of the particles may not be removed. Moreover, manually scrubbing fine mesh lab sieves can damage them.

Tovatech offers two options for ultrasonic sieve cleaning

One is the SRH 4/200 designed to be used in conjunction with a standard Elma ultrasonic cleaner with a size 300 tank, and the other is one of the uniquely designed Easy 50R or Easy 350R ultrasonic cleaners from Elma. These two cleaners can also be used for cleaning small instruments and for sample prep.

The Elma SRH 4/200 Cleans Up to 4 Fine Mesh Lab Sieves

Elma Ultrasonic Cleaner with SR4/200 Accessory Safely cleaning fine mesh sieves is achieved with Elma’s cleverly designed stainless steel SRH 4/200 sieve rotation holder. It is electrically powered and easily fits onto a 300 size Elmasonic ultrasonic cleaner, such as the heater-equipped EP300H or Select 300 ultrasonic cleaners.

Up to four 200 mm (8 inch) diameter lab equipment sieves from various manufacturers are placed into the unit much as plates are loaded into a dishwasher, and held in place by rollers. Once the sieves are clamped into the holder ultrasonic energy is applied while the sieves rotate into and out of the ultrasonic cleaning bath.

Ultrasonic cavitation produced by the EP300H or Select 300 generator-powered transducers creates billions of minute bubbles that implode vigorously against the screen mesh to quickly but safely dislodge trapped particles.

Positioning is the Key

The key to superior ultrasonic cleaning performance is positioning the analytical sieves at an angle so that contaminants removed by cavitation action fall to the bottom of the ultrasonic cleaning tank and are not trapped in the laboratory sieves themselves. Rotation also adds a rinsing action to the cleaning operation.

When the ultrasonic cleaning process is complete, the entire unit is lifted from the tank and placed on a drain board for drying and reuse. But if the sieves are used in conjunction with insoluble particles a visual inspection should be made by laboratory personnel to see if they are geometrically locked in the mesh. If so a careful dislodging by manual brushing is required to remove them.

Summary of SRH 4/200 Ultrasonic Sieve Cleaner Features

Sieve rotation provides fast, thorough cleaning
Highly cost effective for cleaning multiple sieves; saves time and money
Designed for 300 size Elmasonic ultrasonic cleaners
Stainless steel construction for long service life
Sweep mode for homogenous cleaning action
Time and temperature control
Extended utility for other laboratory cleaning requirements

The Specially Designed Easy 50R and Easy 350R Ultrasonic Sieve Cleaners

1.5 Gallon Easy 50R

The powerful Elmasonic Easy 50R and Elmasonic Easy 350R round devices are used in the laboratory environment, to thoroughly clean test sieves, prepare samples, and completely degas liquids.

Elma engineers determined that a round cleaning tank, in addition to matching most sieve configurations, more thoroughly distributes ultrasonic cavitation throughout the cleaning solution. This desirable situation is further enhanced by the absence of drains that have been shown to diminish cavitation action in their vicinity.

Uniform distribution of cleaning action throughout the cleaning solution is achieved with the automatic Sweep mode, which is also ideal for removing soluble particles. Sweep automatically alternates with the powerful Pulse mode to remove insoluble particles when the “Sieve Cleaning” button is activated on the control panel. This helps assure complete removal of all contaminants from sieve screens.

18 Gallon Easy 350R

The Elmasonic Easy 50R ultrasonic sieve cleaner has an internal tank diameter of 9.4 inches, a height of 5.5 inches and a cleaning solution capacity of approximately 1.5 gallons. Mesh baskets or holders for 200 mm (8 inch) and 100 mm (4 inch) diameter sieves can be ordered separately.

The Easy 350R has an internal tank diameter of 23.4 inches, a height of 9.6 inches and a cleaning solution capacity of approximately 18 gallons.

But Wait! There's More!

Other functions handled by these versatile ultrasonic sieve cleaners include solvent degassing and sample prep.

Degassing, whether for HPLC solvents or for preparing fresh ultrasonic cleaning solutions, is accomplished by operating the cleaner in an on-off mode that causes air bubbles to form, rise and burst. This is achieved by selecting the “degas” key to actively lift out gas bubbles.

Dissolving difficult samples and performing chemical extraction in a fast and safe manner is accomplished by using selecting the “sample prep” key. Processing can take place in glass beakers fitted into a special cover or by suspending them at least one cm in a water bath. The sample prep key can also be used for routine instrument cleaning in an ultrasonic cleaning solution using the optional stainless steel mesh basket.

There is also an on-off key for standard cleaning and a timer showing set and remaining time.

The ultrasonic cleaners are fitted to accept an optional laboratory stand and clamp to hold flasks and solvent bottles at the correct position in a water bath with a surfactant.

Contact us for further details on these ultrasonic sieve cleaning systems.

We can address your specific laboratory needs drawing from our vast experience. For effective cleaning the ultrasonic cleaner must use the right cleaning chemistry, operate at the right temperature, and use the correct frequency. The material being cleaned, its tolerance for ultrasonic vibrations, and the type and degree of soil, determine this. Call us and we will quickly help you identify the right combination and we can even suggest accessories that will enhance your cleaning process.