Fix Ultrasonic Processor Problem - 20 kHz, 500W Power

[knopik]

I am dealing with the ultrasonic processor with the frequency 20 kHz. It's output power can be varied from 20% to 100% (500W). The problem is that it doesn't work at 100%. Even at 90% it works only for 1 min. At the power lower than 70% it operates longer time.

Could you help me to find out the reason.

 

[chemisttree]

It's overheating the driver circuit. Cool down the output transistors or heat sink them properly.

 

[berkeman]

I am dealing with the ultrasonic processor with the frequency 20 kHz. It's output power can be varied from 20% to 100% (500W). The problem is that it doesn't work at 100%. Even at 90% it works only for 1 min. At the power lower than 70% it operates longer time.

Could you help me to find out the reason.

Have you asked the manufacturer? Is the installation per the manufacturer's guidelines?

 

[knopik]

It's overheating the driver circuit. Cool down the output transistors or heat sink them properly.

you are right - the problem is in overheating. The piezoelements inside the converter have been broken - the hole in one of it. The converter schould be cooled down with dry cold air, but it is sealed.

 

[knopik]

Have you asked the manufacturer? Is the installation per the manufacturer's guidelines?

There is no specific installation that is required to this us device. I am in touch with the technician from the company where this device has been bought. He suggested me to cool down the converter with dry cold air when using the device continuously at the maximal output power longer than even 10 min. The problem is that the converter is sealed. How to solve it?

 

[chemisttree]

Is the sonic head matched to the output power of the driver? Sounds a bit oversized to me or the design of the equipment is lacking. The equipment is probably sealed for a reason but if you feel brave, by all means... Dremel On!

 

[AlanDonell]

Have you tested the http://www.hielscher.com/ultrasonics/products.htm" for quite some time. No trouble, no overheat. Comes at a price though . However reading your problems I'm lucky I spent the extra bucks
What are you using your processor for? Welding?

Regards,

Alan

 

[knopik]

Hi, Alan.
Thank you very much for your reply. Last year we bought Hielscher UIP1000 (the same as you did). You are completely right - there is no trouble with processor except the quick erosion of the sonotrode's surface. But it is almost nothing with the overheating of a small one (Sonic's&Materials, 500W). Now there are two processors in our lab. Actually we changed convertor and sonotrode of the small device + switch on the 'air cooling' and it more less works at each amplitude (from 20% to 100%).
Both processors are involved in research: examination effect of the ultrasound on the morphology and catalytic properties of nanoparticles as well as formation of bimetallic either core-shell or alloy nanoparticles. And you?
Darya

Have you tested the http://www.hielscher.com/ultrasonics/products.htm" for quite some time. No trouble, no overheat. Comes at a price though . However reading your problems I'm lucky I spent the extra bucks
What are you using your processor for? Welding?

Regards,

Alan

 

[AlanDonell]

The faster erosion is most likely due to higher amplitudes. Erosion results from cavitation and cavitation is a clear sign of ultrasonic action. If the erosion is faster than on the other equipment, this could mean that the amplitude of your first unit was lower. Did you get the power metering device from Hielscher? I suggest you use that with your other unit for comparison.
I use my system for nanoparticle dispersion to make clear coatings with enhanced scratch and UV resistance. I've been working with other brand sonicators before. At that time I thought my particles weren't small enough. I ran through a couple broken converters, too - most of which I had to pay! Switching to Hielscher made a huge difference. My UIP1000 is really good German engineering. Now I get my nanomaterials to be nano.
Regards,
Alan