ROPEX Industrie-Elektronik

The leading supplier of automated and customer-specific film sealing applications for the packaging industry. The differentiating expertise lies in the controlled impulse sealing process.


Hot seam

When tearing open a pack of diapers, sealed cheese slices, flour bags, potting soil and cement bags, screw and plug packaging or space food, who would think that the key to marketable packaging lies in its secure closure? ROPEX Industrie-Elektronik GmbH is the worldwide market and technology leader for impulse heat foil sealing systems. This enables efficient sealing of thermoplastics, in the highest quality and even with complex contours. The company supplies more than 1,000 customers in approximately 60 countries, including many well-known international blue chip companies. 

Film sealing bars and temperature controllers are relatively small but decisive and high-tech components in modern packaging machines. ROPEX Industrie-Elektronik GmbH manufactures these for the specific requirements of its customers. For example, they can fuse foils in fractions of a second to form a seam that is only a few millimetres wide and has a complex outline. In time periods barely longer than a blink of an eye, they are heated to a precisely controlled temperature and cooled down again. In this way, the most efficient systems seal far more than 100 packaging units per minute and sometimes combine several types of plastics or laminates.

Two wooden frames and a door

The graduate engineer Robert Peters founded the company in 1976, at that time under the name "Ingenieurbüro für Mess- und Regeltechnik". Peters started his first attempts at oscillating temperature control with an oscilloscope and two wooden trestles topped by a door as a workbench. This type of temperature control is based on the principle that materials heat up when electricity flows. The cause is the specific electrical resistance, which is also responsible for the current-to-heat conversion – the so-called temperature coefficient. Peters’ idea was to create precisely regulated temperatures by changing the current and signal shape. This marked a technological revolution for film sealing processes.

Peters’ experiments finally led to a technology called impulse sealing. A high-tech process for which ROPEX Industrie-Elektronik GmbH today possesses an expertise unique in the world, and which it continues to develop on an ongoing basis.


The high-tech seam

The sealed seam is the Achilles heel of thermoplastic plastic packaging: if temperatures vary by only a few degrees, the high-tech packaging materials used today are either not sealed tightly enough or parts of the packaging or the product are damaged. Film sealing bars from ROPEX Industrie-Elektronik GmbH produce sealing seams in a reliable process and with highly dynamic temperature control in the millisecond range. This protects valuable products in the packaging process from damage. The strict standards in some industries, for example in the food and pharmaceutical industries, can also be met.

The sealing bars required for this can also reproduce any contours and even three-dimensional solutions. These are used, for example, for the tight sealing of screw caps or tube welds in medical technology.

These products are supplemented by software solutions programmed in-house that precisely control and document the sealing process. This data may become very important, for example in the case of complaints or to prove the proper packaging of highly sensitive products, such as infusion bags.

Technological trends such as the industrial internet of things (IIoT) or big data in conjunction with cloud computing are increasing the demand for these high-tech applications: as an example, in modern packaging systems the temperature controllers communicate with the machine controller via Ethernet, data of the individual sealing processes can be made available for the cloud and stored there for worldwide retrieval.

ROPEX develops new applications in various areas: today, seams of blinds, mattresses, car floor mats or pacemaker batteries, DNA sequencing containers or lithium ion batteries are welded together. 

Minimum width of a seam that ROPEX can perform today:
Longest weld seam produced by ROPEX to date:
Time during which a film sealing bar heats up to 300 degrees Celsius:
Time it takes for it to cool down again:


Growth in Asia

With a 40 percent share of sales, Germany is the most important market for ROPEX, followed by Italy and the Netherlands. ROPEX has been selling its products in the USA since the turn of the millennium, and now generates almost a tenth of its total sales there. Another focus is on Asia, where ROPEX is currently expanding its network with distributors and partners.


Every company and each employee are unique and have a distinct history.  The following texts offer an impression of the motivation, perspective and convictions of the people behind the stories.