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Effective cleaning using the CNp process (Cyclic Nucleation Process), a combination of ultrasonic and pulsed vacuum cleaning in one compact unit. For residue-free cleaning of complex components, capillary cavities, hoses or bulk material.

High-performance ultrasonic baths with pulsed vacuum

After almost three years of development, BANDELIN and LPW realised the first series-produced cleaning device that combines the advantages of ultrasonic and pulsed vacuum cleaning in a compact design. This allows highly effective cleaning processes to be realised economically even at low throughput rates. The uncomplicated set-up, low-maintenance operation and user-friendly operation make the universal compact unit even more efficient.

Versatile for cleaning in machining and additive manufacturing, reprocessing of complex laboratory equipment, medical device manufacturing and electronics.

Simple set up

Plug in the mains plug (three-phase current), connect waste water connection, ready for operation

Double trough version

Intensive cleaning and rinsing at the same time or 2x cleaning or 2x rinsing

Digital control unit

Ergonomically designed user interface, hygienic touchscreen operation

Safe and defined operation

Automatic temperature control, Time programme and fill level monitoring

Low maintenance

Ultrasonic system and the control system are maintenance-free, Maintenance of the vacuum pump is carried out annually


Also for low cleaning volume


For optimally coordinated ultrasonic cleaning, matching baskets, lids and cleaning and disinfection concentrates are available as accessories

Modern touch screen

Split screen for individual display of temperature and remaining programme time of the respective tub. The tubs can be activated individually or simultaneously via the quick function keys, Start and Stop. For convenient replacement of the bath fluid, the tubs can be emptied at the touch of a button. After entering the password, individual process parameters such as the bath temperature and the programme run time can be configured. In addition, the vacuum, ultrasound and heating functions can be optionally deactivated for certain cleaning processes.

Lid with sight glass

Easy-to-operate hinged lid with gas struts for convenient opening and closing. The integrated sight glass enables direct process observation when setting up the unit. The sturdy design of the support arms ensures high durability under cyclic vacuum load. Due to its own weight, an initial tightness of the lid is achieved, which increases after activation of the vacuum. This ensures easy and safe operation.

Level sensor

During the cleaning process, the bath liquid evaporates continuously. Ensuring a sufficient fill level in the cleaning tank at all times is monitored by the capacitive fill level sensor. If the level falls below the minimum level, the cleaning process is interrupted, the heating is deactivated and a warning message is displayed.


The sloping tub bottom allows the tubs to be emptied without leaving any residue for replacing the used cleaning liquid. Rounded tub corners avoid the settling of dirt particles and facilitate the cleaning of the tubs. During the cleaning process, the tub is filled with 28 litres of cleaning solution up to the embossed filling mark. Above the filling mark is the suction opening for generating the vacuum in the chamber space. Due to the very high mechanical forces of the vacuum, the tubs are additionally provided with reinforcing elements from the outside.

Rubberised castor feet

The sturdy, lockable castor feet with a diameter of 10 cm enable easy transport to the unit's installation site. Furthermore, they ensure a secure stand on a wide variety of floor coverings.

Now also with power setting
the CNp 28-2 L

Introducing the CNp 28-2 L, identical to CNp 28-2 but with an additional power setting. CNp 28-2 L gives you even more control and flexibility for your equipment.

Discover the versatility and quality of our CNp range. Whether you are already passionate about CNp 28-2 or looking for advanced options, CNp 28-2 L will exceed your expectations.

Choose the product that suits you best and experience outstanding performance and quality.


excl. 19 % VAT, plus. ShippingStandard shipping Germany: up to 30 kg: 6,90 EUR; 30-50 kg: 49,00 EUR; from 50 kg: 99,00 EUR; Hazardous goods shipping Germany: plus 11,50EUR
(Prices only for Germany and traders)

The SONOREX CNp 28-2 high-performance ultrasonic bath with pulsed vacuum

We have put together an overview of sample cleanings to help you carry out optimal ultrasonic cleaning. Please visit our Youtube channel for more videos.

Ultrasound cleaning

Powerful, piezoelectric oscillating systems are supplied with high-frequency voltage by an ultrasound generator. The oscillation generated is transferred to an aqueous solution where it causes the finest cavitation bubbles to form and implode. By means of ultrasonic cleaning, adhering soiling is effectively loosened from the object to be cleaned and gentle cleaning is ensured.


Ultrasound creates an intensive pressure-pull change in the water, resulting in very fine cavitation bubbles that grow over several cycles and then implode intensively. The resulting high shear forces and micro-jets of the implosions blast off all adhering impurities from the surface in a short time.

Vacuum cleaning

In an aqueous solution, the static pressure is reduced and boiling bubbles are generated. These form even in capillary structures. Due to the spatial expansion of the clearly visible bubbles, the liquid is displaced from the finest cavities and the dirt particles dissolved in them are effectively discharged. When the bubbles implode, unused cleaning liquid is flushed into the cavities. Even capillaries that were previously difficult to wet are reached by the cleaning solution with this process and washed out without residue in the subsequent CNp rinsing process.

Boiling bubble effect

By lowering the static pressure in the liquid, the boiling point of the water shifts to a lower temperature. The water in the tub already starts to boil at a temperature range of 50 - 60°C and finest vapour bubbles form on solid surfaces. When the pressure is increased again, the steam bubbles implode.

Influencing factors for an optimal cleaning result

For the cleaning of a wide variety of components made of a wide variety of materials with complex surface structures, five mutually influencing factors are essentially decisive:


In liquids, ultrasound creates the finest cavitation bubbles, which immediately implode again (cavitation). The resulting forces cause an intensive and gentle detachment of the dirt particles from the cleaning object.


The combined use of chemistry and ultrasound reduces the cleaning time by cleaning time by up to 90 % compared to other methods. Depending on the contamination, it is a few seconds to a few minutes.

Pulsed vacuum

The combined use of pulsed vacuum and ultrasound enables the flushing of complex components that could not be achieved with previous methods.


Many cleaning preparations only develop their full effect at higher bath temperatures. The cleaning fluid is precisely tempered by the unit heater.

Cleaning preparations

A coordinated cleaning concentrate promotes cavitation, reduces the surface tension of the water, dissolves and binds dirt particles. Depending on the type of soiling, different cleaning preparations are used.


excl. 19 % VAT, plus. ShippingStandard shipping Germany: up to 30 kg: 6,90 EUR; 30-50 kg: 49,00 EUR; from 50 kg: 99,00 EUR; Hazardous goods shipping Germany: plus 11,50EUR
(Prices only for Germany and traders)


Nominal ultrasonic power: 300 W per tank
Ultrasonic frequency: 35 kHz
Working capacity: 28 litres per tub
Inner tub dimensions: 510 x 300 x 260/280* mm
Heating capacity: 3,000 W per tray
Vacuum pump power: 1,300 W

All information in the

Product flyer

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Bandelin exhibition stand

Live on site!

We are represented at numerous trade fairs. Visit us at our stand and let us advise you on your ultrasonic application. You can find the next trade fair dates where we are represented in the overview. Please feel free to contact us and arrange an appointment at the trade fair for your request. We are looking forward to your visit!

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