Plastsvetsning av förpackningar

Våra system och lösningar för försegling, svetsning, skärning och stansning av olika typer av förpackningar, såsom tuber, påsar, askar, kartong och blister med mera, bygger på högutvecklad ultraljudsteknik.


Enkelsidig rullsömsmodul

Den enkelsidiga rullsömsmodulen från Sonotronic är särskilt lämplig för kontinuerlig försegling, svetsning och skärning utan inverkan på förpackningen. Modulen kan integreras i befintliga och nyutvecklade maskinkoncept.

An ever expanding application for the continuous ultrasonic sealing method from SONOTRONIC lies in packaging technology.

Here ultrasonic roll seam technology is applied mainly in horizontal and vertical tubular bag machines. Bags with four sealed edges can also be produced by ultrasonic roller seam sealing.

Both the roll seam sonotrode and the anvil are driven in this process so that there is neither slip nor wave formation in the film. No relative movement is generated between the sealing wheel and film by the double drive either.

In addition to the proven roller seam sonotrodes mounted on both sides, SONOTRONIC has now also developed special unilaterally mounted roll seam sonotrodes. In the case of horizontal tubular bag machines the roll seam sonotrode with unilateral mounting can be assembled directly underneath the filled bag.

In addition to the well known advantages of ultrasonic sealing, such as tight sealing of wetted surfaces, optically attractive seams and consistent sealing results, ultrasonic roll seam technology is also characterised by further advantages. In continuous sealing, no thermal radiation is transmitted to the product, which is particularly advantageous in the case of heat-sensitive products such as chocolate.

Unlike thermal methods, ultrasonic technology also enables mono-films to be used because no heat insensitive outer layer need be laminated onto the film. Furthermore, very thin polymer films (15 μm) of high quality can also be sealed by the continuous ultrasonic method, which has not hitherto been successful with thermal sealing systems.


  • Continuous sealing seams
  • Tight sealing seams even on product wetted surfaces
  • No thermal radiation to damage the product or film
  • Assembly directly underneath the bag
  • Sealing of mono-films and very thin films (15 μm) possible
  • No slip or saving of the film
  • Use in VFFS and HFFS machines and for bags with four sealed edges
  • Environmentally friendly and energysaving


Welding width [mm] 2 – 9
Max. welding force [N] 250
Max. speed [m/min] 80
Frequency [kHz] 35
Power of the generator [W] 400
Max. air pressure [bars] 6
Electrical connected loads of the drive [V] / [A] 230 / 4
Dimensions of the module W x H x T [mm] 250 x 428 x 127

Subject to alterations.


Ultraljudshuvud för toppförsegling KSE 250-100

Sonotronic erbjuder nu också en mekanisk förseglingstång med ultraljudskomponenter för fri toppförsegling av stående och plana påsar.

The KSE 250-100 head sealing unit has been specially adapted for the mechanical requirements of an ultrasonic sealing system. As a closed all-in system the head sealing unit can easily be integrated into existing or new bag filling systems, thus enabling manufacturers of packaging machines to convert to sustainable ultrasonic technology with one complete solution and use the whole spectrum of advantages ultrasonic technology provides.

In order to meet the parallelism requirements the ultrasonic system and the sealing anvil are mounted on a common continuous guidance system. This guidance system is arranged in a second plane above the tools so that the sealing area is completely free of additional disturbing contours.

Because of the two-plane design the width of the mechanical sealing tongs is also equal to the maximum sealing width. In addition, the main body of the tongs has been designed specifically to meet the requirements regarding bending strength and guidance accuracy of an ultrasonic sealing system.

The maximum stroke, speed profile and retention time of the head sealing unit can be freely reduced to the specific requirements by means of the servo drive. The servo drive itself is mounted in the vertical axis above the guidance system. The servo drive is coupled to the guidance system by means of crank mechanics with automatic tumbler in the sealing position. The head sealing unit can be mounted customer-specifically, for example over the guide rails at the top or bottom, or is also available with a stand foot housing integrating the servo control.


  • Ultrasonic tools and sealing tongs in one unit
  • Modular sonotrodes in 20, 30 or 35 kHz technology can be used
  • Common guidance system comprising the oscillating structure and anvil
  • Sealing strength specifically adjustable
  • Disturbing contours above tool level (not in the sealing area)
  • Speed profile, stroke and retention time-specifically adjustable
  • High guidance accuracy by means of recirculating roller guide
  • High sealing forces to avoid film displacement in the sealing process
  • Equipped with customer-specific servo drives


Maximum sealing width [mm] 250
Max. stroke [mm] 2 x 50
Max. closing force [N] 2.000
Number of cycles (cycles/min) at max. stroke 50
Max. air pressure [bars] 6
Electrical connected loads 3 x 400 V+N+PE 50 Hz
Reach on anvil side [mm] 95
Reach of sonotrode side [mm] at 35 kHz 336
Dimensions of sealing tongs W x H x T [mm] 250 x 800 x 186
Sealing tong housing WxHxT [mm] 250 x 800 x 700

Subject to alterations.


Tubförseglingsenhet TSE

Den helt nyutvecklade tubförseglingsenheten TSE förseglar ändarna av tuben säkert och tätt med ultraljud.

Tubes and complex laminate structures can be tightly welded or sealed with the individually adapted tool contours of the tube sealing unit. The highly compact, slim unit can easily be aligned with a module package for multi-web presslines.


  • 35 kHz ultrasonic technology
  • Ultrasonic tools and sealers in one unit
  • Complete system for integration in bottler lines
  • Continuous guide system for vibrator structure and anvil
  • Plane-parallel system of sonotrode and anvil
  • Sealing strength adjustable between 50 – 430 N
  • Interfering contours above tool level (not in the seal area)
  • Optional fixed stop


Max. sealing width [mm] 90
Max. stroke [mm] 2 x 30
Max. closing force [N] 430
Number of cycles [cycles/min] at max. stroke 12
Max. air pressure [bar] 6
Reach on anvil side [mm] 164
Reach on sonotrode side [mm] at 35 kHz 456
Dimensions of sealing tongs W x H x D [mm] 90 x 240 x 620

Subject to alterations.


Ultraljudsförseglingssystem för slangformiga påsar

Det nya ultraljudsförseglingssystemet för vertikala (VFFS) och horisontella (HFFS) slangformiga påsar är en innovation inom förpackningsteknik. Systemet levererar helt täta svetssömmar och är extremt material- och energieffektiv.

The cold tools press the tubular bag together for sealing. The ultrasonic oscillations of the sonotrodes then cause the molecular chains in the sealing area to break open with formation of heat and new joints to be formed. In a very short time, excellent quality seal seams are produced.

Production faults are drastically reduced with the use of ultrasound, because the contents themselves are not heated. Also, the contents to be found in the seal area are separated by the ultrasonic effect during the sealing process. The quality of the seam produced and the barrier layers of the bag film are not affected.


  • Consistent sealing results of outstanding quality
  • No distortion of the seals (hot-tack)
  • Expandable seam widths as a result of modular sonotrode systems
  • Reduced film consumption
  • Narrow sealing seams (down to < 1 mm possible)
  • Tight sealing of very thin films, even when they are in contact with contents
  • No destruction of barrier layers
  • Far fewer production faults
  • Reduced maintenance costs
  • Can be used in vertical (VFFS) and horizontal (HFFS) tubular bag machines

The ultrasonic sealing system for tubular bags has been successfully used for years with our partner GEA Food Solutions in VFFS machines.


Ultraljudssystem för blisterförpackningar, brickor, tråg och koppar

Med det patenterade, modulära sonotrodbordet kan blisterförpackningar, brickor, tråg eller koppar förseglas och stansas i ett steg. Detta gör att efterföljande stansmaskiner inte behövs och förpackningsprocessen blir kortare.

Because the sonotrodes, which emit the ultrasound, are arranged in one level welding area, the sonotrode table can be used irrespective of format. It is sufficient simply to change the anvil plate or the receiving tool to change the packaging format. This results in great flexibility of packaging design.


  • Modular system
  • Free formatting
  • Combined sealing and punching
  • Clean, non-sharp punched edges
  • Rapid tool change
  • Long tool life
  • Sealing and punching quality that can be validated

For format-dependent packaging solutions with ultrasound, we not only adjust the receiving tools to the packed goods but also the sonotrodes themselves. Depending on application, sealing and punching tasks are also combined in this case.


  • Format-dependent, customised and application-specific tools
  • Considerable experience in tool design
  • Own tool manufacture

Subject to alterations.


Ultraljudsförseglingssystem för påsar

Ultraljudssystemen används bland annat för att försegla prefabricerade, ståpåsar och plana påsar.

However, various special formats are not only sealed but also punched or cut to size with ultrasound. Zips or valves can also be incorporated at the same time.

The main advantage of ultrasound compared with other technologies is that the bags can be sealed absolutely tightly even when the sealing area is in contact with the contents. Mechanical pre-pressing by the cold sealing tools and the subsequent ultrasound effect force the contents out of the sealing area. The flavour of the product is not changed.


  • Tight seams even in sealing areas in contact with product
  • The taste of the contents is not affected
  • Application-adapted systems

Subject to alterations.


Ultraljudssvetssystem för kartonger

Ultraljudssvetssystemen SONOTRONIC är lämpliga för kartonger som är belagda med en svetsbar yta.

In drinks cartons this coating is usually made from PE. The closures, which are likewise made from PE, are tightly welded to the sealing layer of the carton by ultrasound.

A further application of cartons is welding to blister trays. The layer on the carton must be adapted to the material of the blister. The transparent blisters, which are usually deep-drawn from PET, show the product to its best advantage whilst the welded on carton serves to provide product information.

In order to comply with the special production requirements of food packaging, our ultrasonic system complies with the IP68 safety standard. For the welding tools we use titanium.


  • Welding coated cartons
  • Cold welding components of titanium
  • Subject to alterations.


Samtidig ultraljudsskärning och försegling

Skär- och förseglingsprocess med ultraljud används överallt där det är viktigt att försegla kanterna när de skärs eller för att göra processen effektivare genom att kombinera de två stegen och undvika efterföljande stansning.

The ultrasonic Cut&Seal process is used everywhere, where it is important to seal edges as they are being cut or in order to make a process more efficient by combining the two steps and avoiding subsequent punching. For example, in the packaging industry, the sonotrode table is used, with which blisters, trays or cups can be sealed and punched out in one step.
Cut&Seal is used in the textile industry when welding elastic and non-elastic thermoplastic textiles continuously using the roll seam module or intermittently using upright sonotrodes. The main advantage of ultrasonic Cut&Seal is that the edges are already sealed during cutting, thus preventing subsequent fraying.



  • Combined welding and cutting or sealing and punching of
    • Films and packaging, even if they are contaminated in the sealing zone
    • Elastic and non-elastic synthetic textiles
  • Rapid and reduced process times with good process reliability
  • Joining and trimming several layers in one process
  • No subsequent punching equipment needed
  • Reproducible welding and punching quality
  • Complete monitoring of the process parameters during production
  • Flexible weld design
  • Minimum weld projections
  • Punching edges that are not sharp and are solid and free of lint
  • Environmentally friendly technology
    • Low energy requirement and hence faster cycle times
    • No solvents and additives required for welding
    • Type-specific recycling of welded workpieces


Ultraljudsskärning av livsmedel

Oavsett om det gäller stora industriella bagerier, i konfekttillverkning eller osttillverkning – vår ultraljudsskärteknik är mångsidig i olika applikationer. 

Ultraljud lämpar sig speciellt väl för skärning av spröda, mjuka eller krämiga produkter. Tack vare ultraljudstekniken uppstår ingen deformering av produkten. Således kan även mycket tunna skivor kan kapas. Ultraljudet ger upphov till minimal ytfriktionen och säkerställer rena snitt utan att produkten fastnar på skärverktyget, eller i minimal utsträckning.

Bakery products containing cream or sugary layers, as well as other dough or fat-containing foods, can be cut or trimmed in a controlled way by ultrasound to produce a quality that is visually appealing. The cutting geometries of the tools for longitudinal or cross cuts are individually tailored to product requirements.

As a result of ultrasonic vibrations, only slight product residues remain adhered to the sonotrode, so that to a certain extent, it demonstrates a self-cleaning action.

Because of the ultrasonic vibrations, cutting sonotrodes work with a lower initial pressure than conventional cutters. At the same time, sonotrode wear is less and the cutting quality is considerably better. In addition, the use of ultrasonic cutting systems has a positive effect on the maintenance and down times of the equipment.


  • Pleasing cut and form stability
  • Product-specific cutting geometries
  • Cutting sonotrodes with little product adhesion and self-cleaning action
  • Reduction in maintenance and down times
  • Products cut almost irrespective of consistency

Subject to alterations.