Knowledge Base

Extruder dies | all sizes | variable density | quadrilobe | trilobe

In the process of extrusion, having different dies available to process your product is key to increasing your chances of development success.  This is why we offer a large range of dies to allow us to work with you to find the dies that best fit your formulation needs.

We offer die plates that are excellent for most uses, like our 1 x 1 mm die, however sometimes a more specialist die may be...

Extrusion of catalyst and petrochemical materials

An opportunity in laboratory extrusion with catalyst material.  We have recently had some considerable success with one of our customers working with the extrusion of small quantities of catalytic material.

Extruding catalyst materials for petrochemical and adsorption products

In collaboration with some of its users, Caleva have recently been successful in extruding of small quantities of catalytic material using the Caleva Multi Lab (the first steps of blending and mixing can also be completed in the same multilevel base machine) whilst increasing the surface area/volume ratio of the extrudate produced.

The Caleva Multi Lab is faster and easier to clean

The Caleva Multi Lab (CML) is faster and easier to clean than any comparable bench-top extrusion & spheronization equipment

The best results in the minimum time for your formulation development

 

Guide to the optimum diameter to length ratio of extrudate fragments

Is there a guide to the optimum Length to Diameter ratio of the extrudate fragments?

In the calculations used to demonstrate the data it is assumed that the extrudate is an infinitely long strand. In this case the length of the extrudate has no influence on the data shown. In reality, extrudate is not infinitely long and as the individual strands of the extrudate produced become shorter, the...

How do I ensure consistency during scale up?

Consistency Measurement

A direct consistency measurement of a small sample (generally around 40 g) taken from a process as it is ongoing.  This allows for accurate comparisons to be made quickly, accurately, and repeatable way.

Formulation development - determine optimum powder to binder ratio

Multiple Addition Test

Binder liquid is added to a dry powder mix and the consistency is measured as the mixing and addition of binder progresses.

What type of pharmaceutical or catalyst extruder do I need?

All extrusion processes require the generation of pressure within the material to be extruded. When materials are put under pressure heat is generated. This cannot be avoided but different extrusion types generate different amounts of heat. There are basically three different types of extruder and the one chosen may have far reaching implications on production operations. It is important that...

What pharmaceutical products or drugs can I make in pellet form?

A list of suggested uses for pellets in pharmaceutical applications. 

We are working closely with many partners in a wide variety of industries as well as pharmaceutical. The industries where we are helping our customers to make pellets and extrudates are listed below. 

 

What characteristics should my extrudate have?

Extrusion and spheronization is not always completely straightforward.  A formulation required for spheronization needs to go through the following processes and achieve the following properties.

What are the standard processes in the manufacture of pellets?

Wet Granulation - Granules are formed by the addition of a granulation liquid onto a bed of powder under the influence of an impeller. This is typically carried out using a high-shear granulator or a simpler planetary mixer.

Should I use spheronization or layering to manufacture pellets?

There are two main ways to make small pellets for drug delivery:

  1. Drug layering onto inert starter (or seed) pellets that are bought commercially
  2. Extrusion and spheronization binding the active material in the substrate of the pellet from the beginning

There is no right or wrong way to make pellets. The most appropriate method for your particular application will depend on what you are trying...

Formulation development of catalyst materials zeolite and bentonite?

We always offer our potential users the opportunity to test their formulation with us in our lab. This is to ensure that installing our machines would be the right decision for their formulation development, and/or their production environment.

This short article has been written from notes that Dr Steve Robinson made during trials with catalysts sent to us by a customer and we achieved some...

Do all extruders and spheronizers have the same level of performance?

Product yields (the percentage of the spheroids produced in a batch that are within the size range required) will never be 100%.

However, it is possible to achieve yields of greater than 98% if the formulation, process parameters and the equipment used are optimised. 

Formulation and process parameters are outside the control of Caleva, but the quality of the equipment used is our direct...

Developing a formulation with a tough waxy cosmetic material

We recently had a visitor from Asia who was trying to solve a problem with their cosmetic formulation. The investigator wished to have approximately 1 mm diameter pellets. The formulation presented was a tough, waxy material in irregular broken blocks that were up to about 10 mm in diameter and was unable to be spheronized into the required size or shape.

Can I spheronize a granulation and skip the extrusion process?

In some circumstances it is possible to omit the extrusion stage, but the results may not be what you need.

It is dependent on what you need to achieve with your result and what you want to do in the next phase of the project. Whether or not you decide to include the extrusion stage will depend on what you want to achieve with your project. 

A better therapeutic effect with spheroids

In many cases the main reason for the use of pellets in the manufacture of products is for its controlled release properties. However there are reasons to believe that pellets or spheroids in any case can offer a superior therapeutic effect even when modified release is not the prime objective.

Examples of the terminology used in spheronization and marumerization

Spheronization, marumerization, pelletization and micropelletization all mean the same thing. The manufacture of products in small spheres (spheroids) for use in pharmaceutical (pharma) and catalyst industries. Within each batch the spheroids are of regular shape and size and are quite dense. The products produced by these processes can be called spheroids, spheres, micro-spheres, pellets,...

Do I need a water jacket for cooling on a screw extruder?

The extruder attachment on the Caleva CML does not have a water jacket. Does it need one?

All extruders generate heat and screw extruders generate more than most other extruder types. For this reason, water jackets are generally an integral part of single or twin-screw extruders. 

  • Given the small batch sizes (10 to 100 g) that are optimum for the CML extruder, a well formulated extrudate will...