JEL RRM “Pharma” Drum hoop mixer
With free-fall mixers such as the JEL RRM, the mixing material is moved in the drum purely by gravity.

In this way, particularly gentle mixing processes can be realized – an advantage for products that are sensitive to breakage.

Free-fall mixers are also in no way inferior to compulsory mixers in terms of their range of applications:

In addition to mixing, numerous tasks such as coloring, dispersing or dissolving liquids in solids can be implemented.

The JEL RRM drum hoop mixer is made up of a drum hoop frame with drum holder, a mixing container and a roller conveyor. The roller conveyor serves as the base frame for all other components, such as the drive that sets the rollers and thus the mixing drum in motion.

Depending on the product and mixing task, a free-fall mixer can also be equipped with additional mixing inserts to enhance the mixing effect.

Rhöndradmischer mit dreiflügeligem Mischeinsatz auf Edelstahl für hygienische Produktionsprozesse

JEL RRM “Pharma”: The drum hoop mixer in hygienic design with many options, such as different drum sizes, mixing inserts or protective guards. The product range also includes aseptic drives.

Operation of the JEL RRM drum hoop mixer

The mixing container, often a stainless steel drum, is filled with the mixing material and inserted at an angle into the drum hoop frame. The drum is lashed down with a tension belt so that it cannot slip during operation.

Subsequently, the rack can either be placed on the roller conveyor using lifting tools, or the JEL RRM is extended with an additional ramp so that the rack with the mixing container can simply be rolled onto the conveyor by hand.

Once the rack with the barrel has been placed on the roller conveyor, the mixing process can be started. The wheel starts to rotate around its own axis, thus setting the barrel into a tumbling motion.

Due to the inclined barrel position, a 3D mixing movement is created which evenly circulates the mix inside the barrel. This ensures intensive mixing of all components, even if individual components are only present in small proportions in the overall mixture.

When the mixing process is finished, the rack with the mixing container is lifted or rolled out of the roller conveyor again, the retaining straps are released and the drum can be easily removed.

The entire drum change takes place without tools and without emissions, as the mixing container itself is tightly sealed.

Rhönradmischer JEL RRM mit begehbarer Umwehrung aus Edelstahlgitter, Boden und Rampe.
Detailaufnahme der Unterseite einer JEL RRM Sonderkonstruktion mit Edelstahl-Oberflächen und weißen Laufrollen.

Engelsmann based the development of the JEL RRM Pharma Mixer on industry standards such as FDA, EC 1935/2004 and GMP.

Left picture: JEL RRM “Pharma” with ramp and protective barrier. Right: stainless steel body with high quality finishes and white casters.

Flexibly adaptable to individual conditions and tasks
From fine powders or granular bulk materials to liquids and pasty media

The JEL RRM processes a wide variety of products and does so particularly gently.

In order to perfectly adapt the drum hoop mixer to the respective mixing material, the JEL RRM is equipped with a wide range of adjustment options.

Depending on the application and task, a choice can be made between a constant or variable speed version. Adjustable speeds have the advantage that the mixing movement and thus the mixing intensity can be adjusted at any time. For example, agglomerated products or products that are difficult to mix can be accelerated strongly, while sensitive products are mixed gently at a low speed.

Especially for operators who are confronted with frequent product changes or differences in product consistency, variable speed adjustment is a useful option.

Mischeinsatz mit drei Flügeln und Abstreifleisten für den Pharma-Mischer JEL RRM im Hygienic Design
Frauenhände heben einen Dreiflügelmischeinsatz aus dem Rhönradmischer JEL RRM

Available in sizes from 50 to 300 liters, the free-fall mixer covers a wide range of tasks. In some cases, however, the three-dimensional movement of the drum hoop mixer is not sufficient to achieve the desired mixing effect. Thus, additional mixing aids are used for difficult-flowing bulk materials, such as a three-blade mixing insert.

This mixing insert consists of a shaft with three mixing blades made of perforated stainless steel and can be easily inserted into the drum if required. By putting on the drum lid, the mixing insert is firmly anchored in the drum without having to be screwed into it. If required, it can also be removed again quickly and without tools, for example for cleaning purposes or when changing products.

As soon as the mixing process starts, the mixing material virtually slides through the openings of the mixing insert due to the tumbling motion of the drum. The mixing insert itself remains static in the drum, so that the mixing process is particularly gentle on the product.

From standard to very special
Starting from the basic model, the JEL RRM can be adapted to your specific requirements and the conditions on site.

Very special customer requirements can also be solved constructively within the scope of a special design.

Drum hoop mixers that can hold up to four drums or mobile models are just a few examples. Various mixing containers such as small containers, plastic or glass bottles can also be clamped in the JEL RRM after design adaptation. For hygiene-sensitive applications, aseptic drives and compliant sealing materials are part of the standard equipment.

Sonderkonstruktion des Rhönradmischers JEL RRM, um das Mischgut in einem Glasbehälter zu verarbeiten.

Special design for holding a glass container

Detail Mischbehälter aus Edelstaht

All parts are made of high quality stainless steel

The safety plus: protective barriers

To ensure additional operator protection, it is recommended to use safety barriers, which are available in different designs: made of safety glass, Plexiglas or aluminum mesh. They prevent the operating personnel from accidentally getting into the moving parts of the mixer during operation.

Rhönradmischer JEL RRM mit begehbarer Umwehrung aus Edelstahl.
Totale Rhönradmischer JEL RRM im Hygienic Design mit Schutzumwehrung aus Glas für die Pharma-Branche

From the small protective hood with hinged cover to the walk-in safety barrier with operating platform – safety barriers are available for all space conditions. If required, they can also be embedded in a consistent hygienic design concept.

Top priority in hygiene-sensitive areas:
Avoid contamination

The equipment must be easy and thorough to clean. Surfaces on which product can be deposited must be avoided. Likewise, dead spaces where product residues could get stuck. And there is also no space for loseable parts such as screws that accidentally get into the product.

In the case of the hygienic version of the JEL RRM drum hoop mixer, this is achieved primarily by design measures:

The roller conveyor consists of a single welded stainless steel component instead of various assembled individual parts.

The roller conveyor is stiffened by cross tubes which, thanks to their round shape, minimize the risk of product residues or contamination.

In the Hygienic Design version, the drum support does not consist of a tension belt, but of a double stainless steel casing, with a half shell permanently installed in the rack of the JEL RRM.

Once the drum is inserted into the rack, the second half shell is placed on top of the drum. Both shells are tightened by means of star grips so that the mixing container has a secure hold.

To ensure that the drum remains firmly seated in the JEL RRM during operation, both half-shells are coated on the inside with a special FDA-compliant anti-slip coating.

The drum hoop mixer is driven by an aseptic motor. The special housing makes it ideal for use in hygiene-sensitive industries.

Unlike drum mixers, where fixed mixing tools are installed in the mixing vessel, the drum interior of drum hoop mixers is completely free of dead space.

The entire mixer is made of stainless steel with varous options regarding surface treatments. Grinded, stained and passivated, or if necessary, electropolished surfaces with roughness depths of 0.8 µm and below.

The optionally available three-blade mixing insert, which can be inserted into the drum to optimize mixing intensity, was also put to the test for the Hygienic Design variant: The body of the mixing insert consists of a single, solid stainless steel part – with no losable parts such as bolts and nuts. The wings of the mixing insert are equipped with plug-in spring clips which can be easily removed for cleaning purposes and then plugged back on again.


Free-fall mixers such as the JEL RRM drum hoop mixer can be used for a wide range of mixing tasks. By dispensing with rotating mixing tools, this mixer type impresses above all with its gentle, low-maintenance and energy-efficient mode of operation. The pharmaceutical version of the mixer is hygienically designed and complies with guidelines such as GMP. Documentation packages for qualification are included as standard.