Globally renowned as a pioneer in powder processing innovation, Hosokawa Micron invented the classifier mill concept more than sixty years ago and has continuously developed the technology and product since then to accommodate the evolving requirements of manufacturing industries. Launched by Hosokawa in 1962, the original ACM Air Classifier Mill was the first mill of its type available and it continues to be a very popular choice with customers from many sectors.
The compact design, intuitive arrangement of its components and flexibility of the entire range still set it apart from other classifier mills. Robust, well-engineered and offering an array of useful features and benefits, the equipment enables the efficient comminution of difficult-to-process, heat-sensitive and sediment-prone materials and combines impact milling with dynamic classification to accurately control particle size, distribution and cut point.
The ACM Air Classifier Mill range comprises six unique models – including two user-friendly, laboratory-scale models for research and producing small batches – and can now be fitted with newly developed E3 Beaters, which increase throughput by up to 20%, lower energy consumption and improve product quality.
Air Classifier Mill
Operating in the medium to fine particle size reduction range the Mikro ACM delivers guaranteed, accurate particle size because of the highly efficient, variable speed dynamic integral air classifier and achieves a steep particle size distribution with minimum ultra fines.
Continual improvement in the Mikro ACM has created an extensive product range suitable for processing a wide range of even difficult to handle materials. In generating no potentially damaging increases in product temperature the ACM is suited to milling even sticky, fatty or oily materials and has achieved considerable success in the milling of chocolate.
This type of mill operates on the principle of impact grinding and employs high rotor speeds with a striking edge velocity of up to 120 m/s. Size reduction takes place by the impact of material particles on the rotating grinding surfaces (hammers or pins) and on the fixed liner or grinding track. Designed with an integral classifier, particle size, distribution and cut point can be accurately controlled by variable classifier speed.
Air Classifier Mill Specifications
The core industries that trust the Hosokawa ACM Air Classifier Mill to provide them with excellent high-quality powders use it to process materials such as sugar, cacao, xanthan, starch, talc, pectin, dried fruit, kaolin, limestone, epoxy, polyester, E-PVC, fungicides and herbicides, tartaric acid, polyamide, lactose, ascorbic acid, aluminium hydroxide, formaldehyde, silica, ammonium phosphate, gypsum and calcium sulphate, amongst many, many other materials.
NEW – E3 Beaters
Existing and new ACM Air Classifier Mills from Hosokawa can be equipped (or easily retrofitted) with our newly developed E3 Beater, which is an excellent option for powder processing industries. This game-changing addition was developed with gentler, more effective material handling in mind, as well as the requirement for processing equipment to be more economical and energy-efficient – hence the E3 brand name.
Vigorous R&D, testing (including comparisons with competitor classifier mills) and real-life customer case studies have proved that the ACM Air Classifier Mill, fitted with our uniquely designed E3 Beater, can substantially enhance throughput by up to 20% while simultaneously reducing the mill’s energy usage and improving the quality of the processed powder by providing lower fines content, lower temperatures during processing and lower levels of product contamination through abrasion. Further advantages of the E3 Beater include the reducing of production costs and the equipment becoming even more durable and easier to clean.
For customers with an existing Hosokawa ACM, the process of retrofitting an E3 Beater is easy, involving minimal downtime and a simple replacement of the current grinding disc, with no other modifications required. Customers choosing to invest in upgrading to the enhanced grinding disc will see a return on investment in less than a year.
The versatile ACM Air Classifier Mill is used for the fine and ultrafine impact milling, drying and classification of soft to medium-hard materials, including heat-sensitive products and those prone to sedimentation. The ground-breaking mill is consistently a very popular choice for the pharmaceuticals, chemicals, powder coatings, pigments, food and minerals industries.
Compact, robust and hardwearing design
A Hosokawa Gen4-enabled ACM Air Classifier Mill is regularly used by our in-house Technical Services team for product testing and contract manufacturing batches of powder on behalf of our customers. Our pioneering Hosokawa Gen4 digitalisation solutions and software – uniquely created for powder processing industries – was partly developed using an ACM Air Classifier Mill and successfully optimises our milling processes, productivity and profitability, while reducing downtime.
The space-saving ACM Air Classifier Mill is an extremely efficient all-rounder for size reduction and classification of a variety of materials. The product is also suitable for a combined grinding and drying process. The ACM boasts a number of operational advantages, too, such as gentle grinding at low temperatures, energy-efficiency, wear protection, an easily adjustable and very precise cutting action, low noise emissions and steep particle distribution capability.
Material pneumatically feeds into the ACM Air Classifier Mill from the top, allowing for optimised throughput rates. Size reduction of the raw material happens effortlessly as the materials impact against the grinding rotor and fixed liner at high speed and become smaller particles. As an example, a striking velocity of 140 m/s accomplishes a fineness value of d97=10µm.
The product becomes trapped in the downstream fan’s cooling, conveying and classifying airflow, with the product being drawn through the mill and routed along the guide vanes of the vane ring.
Unique to the ACM Air Classifier Mill is its integrated dynamic classifier. The guide vane ring distributes the processing material and air mixture homogeneously to the rotating classifier wheel and, due to the different forces and the masses of the particles, the product is separated into coarse and fine material in the classifying zone. The classifying wheel rejects the course material and returns it to the grinding zone for further size reduction. The finely milled material exits the mill only after successfully passing through the classifying wheel. The adjustable cut point feature is a useful function of the classifying wheel speed, allowing for the manipulation of the precision of cut, even when the ACM is mid-operation.
Hosokawa’s ACM Air Classifier Mill can be used individually or as part of a bespoke process system that may include additional Hosokawa-brand and ancillary equipment, as well as a tailored Hosokawa Gen4 digital strategy solution for connected smart manufacturing, such as remote monitoring.
Complete milling systems – featuring the ACM and elements such as hoppers, cyclones, air filters, sieves, control units and bag fillers – can be designed, engineered, manufactured and commissioned in-house by Hosokawa Micron Ltd to specific customer requirements and our expert sales and engineering team would be pleased to collaborate on the perfect configuration for your application.
For further information about the digitalisation options and solutions available through Hosokawa Gen4, including remote monitoring, please refer to the Digital Services section.
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