The benefits of pelleted animal feeds are well known. Less wastage, easier to store and transport and no risk of ingredient separation are all good reasons to pellet animal feed.
However, pelleting is not without its own challenges. The measurement of pellet durability became important when livestock farmers began rejecting poor quality pellets.
Many animal feed compounders test the durability of their pelleted rations. This is because it is important to strike a balance between the pellets being too hard and thus difficult to eat, or too weak, in which case the feed became dusty and much was wasted.
Accurate measurement of pellet durability enables optimum inclusion rate of pellet binders. Too little binder and the pellets breakdown; too much and money is wasted. Lignin, molasses, starch and steam are popular pellet binders.
Today the biggest cost is energy. Pelleting is an energy intensive process. Pelleting presses operate at pressure and so consume power therefore the aim is to minimise the energy cost and maximise the pelleting efficiency.
The new Holmen range of Pellet Testers is the culmination of 15 years involvement with the pelleting industry. We have now created a stable test environment that gives repeatability and consistency to the test results. The Pellet Durability Index (PDI) which is obtained from the Holmen Pellet durability testers sets the benchmark which is used in most parts of the world.
The New Holmen NHP100 portable pellet durability tester is a versatile affordable machine.
Being portable it can be easily transported around different testing locations requiring only to be placed on a flat stable surface to provide good results.
It operates by loading a sample of pellets into the test chamber which cascades them in an air stream causing the pellets to collide with each other and the perforated hard surfaces within the test chamber.
After the test cycle the subject pellets are ejected for manual weighing. The ‘pellet durability index’ (PDI) is the difference between pellet weight before and after the test recorded as a percentage.
The New Holmen NHP100 provides the ability to manually calculate test results with a repeatability accuracy of ± 1.0% PDI.
The New Holmen NHP200 pellet durability tester is the flagship of the New Holmen pellet testing range.
It is designed to provide benchmark test results calculating the ‘pellet durability index’ (PDI) with a repeatability accuracy of ± 0.1% PDI.
The machine is ideally suited to busy laboratories and testing environments. It provides the possibility for a supplier of pellets to test them under different conditions i.e. recipe, age, temperature to provide accurate results and refine pellet production to suit their customers parameters.
The NHP200 is an automatic test machine that will, once a test sample has been loaded, provide a PDI result without user intervention.
With a reduction in labour input the possibility of human error is eliminated.
Results are displayed on a LCD readout or if the printer option is chosen as a hard copy record.
The New Holmen NHP300 in line pellet durability tester is designed to automatically provide test results of pellet samples directly from a transfer duct.
The system automatically takes a sample, performs the test and returns the sample back to the transfer duct in the process calculating the ‘pellet durability index’ (PDI) with a repeatability accuracy of ± 0.1%.
The machine is ideally suited to a busy pellet processing plant where optimum control and production effectiveness is necessary to eliminate wastage, maintain pellet quality assurance and reduce costs.
The PDI data can be either sent to an independent display controller or directly to the mill control on an ASCII format.
In addition to calculating the PDI, when operated via a Direct Interface ASCII Serial Control, the NHP300 also has the ability to calculate the amount of 'dust' (Fines) in the sample. This is a useful feature for when dust measurement is an important part of the quality control process.
The NHP300 is a modular system and can be designed and installed to the customers requirements and application.