Dry Extrusion Pelleting Press – UMT
Custom Powders offers the possibility of the pelleting of dry powders or a mixture of powders. With this technique the raw material, if required with water or a different type of lubricant, is fed to the machine where a number of special rotating rolls push it under considerable pressure through a die. Depending on the dimensions of the die, this will give a cylindrical product with a diameter in the range of about 2 – 4 mm and a length varying from a couple of millimetres to a couple of centimetres. This technique is often used for raw materials that are not really sensitive to pressure, temperature differences or contaminations. 
It is a relative simple technique that produces a product that will be relatively easy to dose
and pneumatically transportable in a cost effective manner.
Download the print version of additional information on this dry extrusion technique, or read here for further information.
Dry Extrusion Pelleting Press UMT
Custom Powders in her search for new techniques invested a couple of years ago in a pelleting technique. In this technique we saw a suitable addition to our existing range of dry granulation techniques. We have chosen the V3–75C pelleting press from Simon Heeze (UMT). This technique distinguishes itself from other pelleting presses in that it has a vertical position of the die instead of a horizontal position.
How this technique works
Pelleting is a technique that can be applied for a lot of powders with different structures, binding characteristics, particle sizes, moisture contents, densities, fibrous, powdery and granular or paste like products. Depending on the product it can be necessary to add water, some kind of lubricant or some kind of binder in order to enable pelleting.
The raw material is pressed through a die by means of special rolls that force the material through the die with considerable force, forming spaghetti like product that can be cut off by knives at the desired length. The result is a cylindrical product that is fairly homogenous as far as length, thickness and diameter are concerned. Depending on the chosen die the particles will vary in diameter from 2 – 4 millimetres with a length of 3 – 5 centimetres.
Selecting the right die is of the utmost importance. Custom Powders has available a range of standard dies for our customers but in many cases specific dies will need to be ordered to make sure that the desired specification can be achieved. The specific shape and form of the die does not only influence the length and diameter of the end product but also has an effect on the hardness, the moisture content and temperature of the end-product. Cleaning of the dies is a very intensive and timely process and often it is better to choose for a die just for your application.
Pelleting is often combined with pre-mixing of the raw materials and/or cooling/drying of the end product followed by sieving.
Why to choose this technique?
This technique can offer an alternative in cases where direct extrusion or dry blending/compaction is not possible or commercially not viable. The end-product normally is a free flowing product that is virtually dust free and therefore easier to handle and dose. Often the main goal is to increase the density of the product, to improve the shape or to mix it with filler or improve the end product in a different manner. These applications do simplify the storing, transportation or repacking of the product but often also improve the dissolving characteristics of the product.
Pelleting is often chosen when relatively insensitive products need to be processed in a cost effective manner.
Examples can be found in plastic additives, several chemical products and animal feed products.
As with most of our processes we work closely together with the supplier of the equipment who normally does the initial developing work on their lab equipment. On the basis of these initial tests Custom Powders can than usually upscale to our production equipment.
Quality:
The machine is designed in cast iron with stainless steel contact parts and it is suitable for chemical products, plastic additives, feed applications and relatively insensitive food products.
Explosion rating:
Suitable for products with a low of middle high explosion rating (ST1 – ST2)
Availability:
This equipment is available in Helmond (NL) as well as in Crewe (UK).