Pin Mill Controls Particle Sizes
A new 24-inch (610 mm) diameter pin mill model CIM-24-MS from Munson Machinery grinds, sizes, de-agglomerates and homogenizes friable or other materials into controlled particle sizes, from coarse to fine (400 mesh).
Also known as a centrifugal impact mill, it is equipped with a stationary outer disc and a rotating inner disc, both of which are precision-machined and studded with impactor pins. As material enters through the center of the outer disc, centrifugal force created by the rotating inner disc propels the material radially through a destructive path of five intermeshing rows of rotating and stationary pins. This produces the tight particle size desired by controlling the infinitely-variable rotor speed.
Higher speeds to 5,400 RPM pulverize friable powders, flakes and granules into fine grinds while killing any insects, eggs and larvae. Slower speeds down to several hundred RPM provide coarse grinding and de-agglomerating. Typical applications include rice flour, starches, sugars, spices, vitamin powders, grains, sodium compounds, fertilizers, resins, clays and other friable products.
The infeed of the stationary outer disc can be equipped with flanged, threaded or other fittings for gravity-fed or inline-pneumatic applications. The rotating disc rides on oversized pillow-block bearings and is driven by a 40 hp to 60 hp (30 to 45 kw) motor with V-belt/sheave arrangement, delivering high throughput per hp/kw compared with machines employing screens, hammers, knives or rolls.