Equipment for the manufacture of pellets

Switch quickly between different materials with this easy to clean CE marked, top quality extrusion and spheronization system. An example of reliable and efficient British engineering at its best - this is the best option for your pellet production and is backed by the highly acclaimed support from Caleva Process Solutions.

The Caleva system gives you the ability to vary the density of the extrudates. Fine-tune your process to be ideal for your product properties and the intended use of your pellet or extrudate. This allows you to scale-up from your formulation development with any laboratory benchtop extruder.

Caleva is a company with almost 100% of its focus on equipment for extrusion and spheronization. It is our key and core business. We are passionate about our equipment and support being the best there is in this field.

The Caleva Variable Density Twin Screw Extruder

The Variable Density Twin Screw Extruder (VD-TSE) is Caleva's largest scale extruder, capable of producing up to 150kg of extrudate per hour (formulation dependent). Caleva's large-scale production extruders are used in production for a wide variety of industries by both large manufacturers and smaller contract manufacturers around the world. The VD-TSE can be used for anything from pharmaceutical products to animal feed. Outputting consistent and reliable extrudate regardless of your industry is what the VD-TSE is designed to do.

  • Designed to provide excellent results and offers the ability to output variable density extrudate.  Learn more about Variable Density Extrusion
  • Designed to withstand a higher axial load than standard to reduce risk of damage in use by operator over a wider range of industries

The Caleva Spheronizer 700

The Caleva Spheronizer 700 (S700) can produce up to 150 kg of pellets every hour (depending on your formulation) and works most efficiently with loads between 1 kg to 15 kilos. In a recent manufacturing installation, very small pellets were required, but in loads greater than 4 kilos the size of the pellets increased slightly beyond their required measurements. Using the flexible batch size of the S700, meeting the formulation's requirements was a simple and easy adaptation.

A few key features:

  • Air blast technology to enhance efficiency during continuous operation
  • Batch operation with fully automatic discharge
  • Water jacket for heating or cooling of the product



Surprisingly Compact

Good management of space in a production environment is often key to ensuring a high productivity rate. Having as much equipment as possible whilst still ensuring there is enough working space becomes difficult with large machinery.

For an extruder that can output around 150 kg per hour, people are often surprised by it's small footprint.



Superior Caleva Design

Disc Groove


There is a groove under the spheronization disc to prevent water from running under the surface of the disc and entering the drive shaft - only available from Caleva

With very wet products, or as a result of condensation, water sometimes collects on the underside of the spheronizer disc. A safety groove is provided so that water does not creep to the centre of the disc when it is not spinning and run down into the drive shaft and motor. The shaft seal air purge on other equipment in the market may not operate when the machine is switched off.


Barrier Shield


On the base of the spheronization chamber, there is a barrier shield. This is to prevent cleaning water ingress into the drive shaft

Water can be drained from the spheronizer bowl and be removed down the drainage hole. Any remaining water can creep into the drive mechanism. The secondary shield on the Caleva machine will prevent this from happening, potentially giving longer life to the equipment.


Integrated Air Blast


To prevent blockages during operation, the S700 has an integrated air blast gun for immediate hand cleaning by operators. This stops the need to turn the machine off each time a blockage or build up occurs.

During continuous operation there is a tendency for moist pellets to stick around the discharge door area. If the door closes on, and compresses these pellets then an incomplete door closure can occur, which disturbs operation of the equipment.

Caleva spheronizers are fitted with a hand-held air blast gun to allow easy cleaning from both sides of the door opening as part of the operation to easily and efficiently prevent product build-up and operational disturbance.


Product discharge system

A gradient discharge door (rounded for gentle product flow) with pneumatic hinges, provides gentle product management and direction changes of spheroids that are still soft and wet. An angular system can damage the shape of the soft discharging spheroids

Spheronization Disc Lifting

The Caleva production spheronizer has a lifting device built into the machine. This makes removing the disc quick and easy, and is power operated by buttons on the side of the control panel.Hoist buttons


Use on uneven flooring

To avoid excessive wear, large spheronizers are designed to be placed on flat surfaces. The Caleva machine is designed to be levelled on uneven floors.  Levelling is important for smooth operation of a heavy disc rotating at speeds up to 400 rpm.

Air purge under the disc

The air flow on the Caleva machine is variable according to user requirement. This requirement can vary with batch size and formulation.

Rounded discharge chute

Similarly to the gradient discharge door, a gradient entry to the discharge chute provides gentle product management and direction changes of soft and still wet spheroids. An angular system can damage the shape of a proportion of the soft discharging spheroid product.

Product Temperature

For some formulations it can be important to know the product temperature of extrudate coming through a die, or the pellets inside the spheronization chamber. These Caleva machines have a thermometer that links to a display on the control panel, giving you a constant product temperature reading.

Controlled Pellet Discharge

If the spheronizer disc speed is too high during product discharge then pellets can either stick on or pellets can be damaged. On the door open command (automatic or manual) the speed of rotation of the disc is automatically slowed to an optimum rate for discharge before the door is opened.

Backed by Caleva Expertise & Service

Backed by Caleva Expertise & Service


Scott has recent experience of some quite challenging extrusion and spheronization projects where, with some careful thought, success has been possible, even though at the outset it was considered doubtful. When safe to d Scott is always keen to visit customer sites to demonstrate how our equipment can help.  Contact Scott directly +44 (0) 7495 527790 or email



Variable Density Twin Screw Extruder

Technical Specification

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Caleva Production Spheronizer 700

Technical Specification

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Options & Further Considerations

Practical Use Examples

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Caleva Production Equipment

General Brochure

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Dawn Philips
By Dawn Philips
9 Jun 2021 in Product Yield, Scale Up and Manufacturing

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