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The element

BLT transducers — single frequency

A bolt-clamped Langevin transducer is the piece that actually makes the sound: a piezo stack clamped between a metal front mass and back mass, tuned to one frequency. It is what sits inside an immersible box or bonds to a transducer plate.

Five frequencies, single note. If you need one element to do both a coarse pass and a fine pass, that is a dual-frequency element.

We sell them as elements — for building plates, for OEM machines, and for repairing a tank whose bonded array has gone deaf rather than scrapping the vessel.

The elements

Five frequencies

Frequency is chosen by the deposit and by what the substrate will take — 28 kHz for scale and hard carbon, 40 kHz for general engineering, 68 kHz where the finish matters, 80 and 130 kHz where it barely matters at all. Power is per element; a plate or box carries several. Four are stock; 80 and 130 kHz are sourced against a firm order.

BLT ultrasonic transducer, 100 W at 28 kHz100 W · 28 kHzThe heavy element — scale, hard carbon and weld deposit.Enquire →BLT ultrasonic transducer, 60 W at 28 kHz60 W · 28 kHz28 kHz at lower power, for smaller plates and tighter packing.Enquire →BLT ultrasonic transducer, 60 W at 40 kHz60 W · 40 kHzGeneral engineering work and a better surface finish.Enquire →BLT ultrasonic transducer, 60 W at 68 kHz60 W · 68 kHzFine and precision work where the substrate will not take a heavy band.Enquire →Single-frequency ultrasonic transducer element, 80 kHz80 kHz · to orderFine particulate off plated, polished and delicate surfaces. Power and dimensions confirmed at quotation.Enquire →Single-frequency ultrasonic transducer element, 130 kHz130 kHz · to orderThe gentlest band we supply — sub-micron particulate, optics and coated surfaces. Power and dimensions confirmed at quotation.Enquire →

Element count, spacing and bonding are specified against the plate or the vessel. Dimensions and mounting detail are confirmed at quotation.

Specification

By part number

Part numberFrequencyPowerWhat it is for
KT300-28khz-100W28 kHz100 WThe heavy element — scale, hard carbon and weld deposit
KT300-28khz-60W28 kHz60 W28 kHz at lower power, for smaller plates and tighter packing
KT300-40khz-60W40 kHz60 WGeneral engineering work and a better surface finish
KT300-68khz-60W68 kHz60 WFine and precision work, where the substrate will not take a heavy band
Assigned at quotation80 kHzConfirmed at quotationFine particulate off plated, polished and delicate surfaces — sourced to order
Assigned at quotation130 kHzConfirmed at quotationSub-micron particulate, optics and coated surfaces — sourced to order

All of these are bolt-clamped Langevin elements: a piezo stack clamped between a front and back mass, tuned to one frequency. Power is the rating of a single element — a plate or an immersible box carries several, and the total is set by the tank. Dimensions, stud thread and cable length are confirmed at quotation against the plate or vessel they are going into.

The first four are stock and ship without a lead time. 80 and 130 kHz are sourced against a firm order — we will not quote a power or a dimension on those until the order is placed and the element is specified against the plate. Other frequencies and powers exist and can be sourced the same way.

Need one element to run a coarse pass and a fine pass in the same tank? That is a dual-frequency element — 25/45, 28/68, 40/80, 40/130 and 80/130 kHz.

Only after a generator? Read this firstOpen

We do not sell a generator on its own to drive transducers we have not specified, and we do not sell transducers to run on a generator we did not supply. It is not a policy about paperwork — the two are tuned to each other, and an unmatched pair usually means no cavitation, a drive running hot, and both halves replaced inside a year.

There is no warranty on an unmatched pair. If you already own one half, tell us what it is and roughly when it went in and we will tell you where you stand before you spend anything.

Why that is — the five things that have to line up →

Pairing

What drives them

BLT elements run on the multi-frequency VarioSonic G4 — the same generator that drives our immersible boxes. They do not run on the rod-resonator SonoDrive G5, and a rod does not run on a G4.

VarioSonic G4 generatorNine models · 800 to 1,500 W · single or dual frequencyPick a model → Immersible transducersThe same elements, sealed into a box built to your tankSpecify a box →
How it is sold

The generator and the transducer are bought together

A generator is tuned to the transducers it drives. Four things have to line up: the frequency the generator tracks, the total capacitance of the array wired to it, the impedance and phase that array presents once it is in the liquid, and the voltage across the group under load. We specify all four against each other, so the pair is quoted, built and commissioned as one item.

What goes wrong when they are not matched

The label is not the loadTwo transducers both marked 40 kHz are not the same electrical load — they differ in capacitance, in phase, and in how the assembly moves. A generator is tuned to a particular array, not to a number on a plate.
The tuning is inside the generatorA matching network — transformer ratio and a tuning inductance — cancels that array's capacitance so the drive sees a near-resistive load at resonance. Change the array and the power goes into heat and reactive current instead of cavitation.
Tracking only has a windowThe generator hunts for resonance within a narrow band around its design frequency. A stack outside that window is never found: the drive sits off resonance, runs hot, and trips or limits.
Power has to match both waysOverdriven, the ceramic depoles and the bond lines and the radiating face fail years early. Underdriven, there is no useful cavitation at all — a bath that looks like it is running and does not clean.
The cable counts tooCable capacitance sits inside the tuned circuit, which is why the length is quoted with the set and should not be extended on site.

A new generator will not rescue an old set. Transducers age — output falls away, the resonant point drifts and the impedance climbs — so an older array is no longer the load a new drive was tuned for. A set of mixed ages is worse again: the weakest element pulls the rest off tune and the drive spends its power hunting for a resonance that has moved. What you get is a generator running hot or dropping out, a bath cleaning unevenly, and transducers failing earlier than they should — and from the outside there is no way to tell which end is at fault, so you end up replacing both anyway.

There is no warranty on an unmatched pair. Equipment warranty covers a generator and transducers supplied and matched by Misonics. A Misonics transducer driven by a generator we did not supply, or a Misonics generator fitted to transducers we have not specified, is not covered — we have no way to characterise the combination, so we will not stand behind it. If you already own one half, tell us what it is and roughly when it went in, and we will tell you where you stand before you spend anything.

Enquire about BLT elements

Tell us the frequency and power you need, how many elements, and what they are going into — a plate you are building, an OEM machine, or a repair. If it is a repair, say what the tank is and how it failed.

Questions

BLT transducers, answered briefly

What is a BLT transducer?
BLT stands for bolt-clamped Langevin transducer. A stack of piezoelectric ceramic rings is clamped under high pre-load between a metal front mass and a back mass by a central bolt. Driving the stack with an alternating voltage makes the assembly expand and contract at its tuned frequency, and the front mass radiates that motion into whatever it is bonded to. It is the element inside every ultrasonic cleaning tank, immersible box and transducer plate.
What frequencies and powers do you hold?
Four are stock: 100 W at 28 kHz, 60 W at 28 kHz, 60 W at 40 kHz and 60 W at 68 kHz. 80 kHz and 130 kHz are sourced against a firm order, with a lead time — power and dimensions on those are confirmed at quotation, not quoted off a list. Dual-frequency elements are on their own page.
Can one element do two frequencies?
Yes. A dual-frequency element is built with two resonances rather than one, and the generator switches between them — a coarse note to break the deposit, a fine note to clear what it loosens, in the same tank off the same array. We hold five pairings: 25/45, 28/68, 40/80, 40/130 and 80/130 kHz. Dual-frequency elements →
Can I buy transducer elements on their own?
Yes, for building transducer plates, for OEM machines and for repairing a tank whose bonded array has gone deaf. What we do not do is sell elements to run on a generator we did not supply, or a generator to drive elements we did not specify. The two are tuned to each other and there is no warranty on an unmatched pair.
How many transducers does my tank need?
It follows the tank volume, the soil and the duty, not a rule of thumb off the litres. Element count, spacing and bonding pattern are specified against the plate or the vessel. Send the tank dimensions and what you are cleaning and we will work it out.
Which frequency should I choose?
28 kHz for scale, hard carbon and weld deposit. 40 kHz for general engineering and a better surface finish. 68 kHz for fine and precision work where the substrate will not take a heavy band. 80 kHz for fine particulate off plated and polished surfaces. 130 kHz for sub-micron particulate, optics and coated surfaces. Frequency follows the deposit and what the surface will tolerate, not the machine.
Can I replace a dead transducer on my existing tank?
Often, yes. A bonded array that has gone deaf can usually be re-elemented rather than the vessel scrapped. We need to know what is in there now, what generator drives it and roughly when it went in. If the generator is not ours, tell us what it is before you spend anything.
What is the difference between a transducer and an immersible?
The transducer is the element. An immersible is a sealed stainless box with several elements bonded to its inner face and a cable gland, built to hang in a tank you already own. A transducer plate is the same idea without the box, bonded directly to the vessel wall or base.
Do they come with a generator?
They are quoted with one. The generator and the transducers are a matched pair — the drive is tuned to the load the elements present, and an unmatched pair usually means no cavitation, a drive running hot and both halves replaced inside a year.