Roller compactor Roll design

Certainly, a key enhancement that highlights today s pharmaceutical industry s state-of-the-art roller compactors, is programmable logic controllers (PLCs). They are used to control and monitor mechanical parts that regulate screw feed rate, roll speed, roll pressure, roll gap, vacuum deaeration, and mill speed. This section will not discuss PLC designs as it relates to compactor design features and advancements. 

Currently, one manufacturer of roller compactor equipment for the pharmaceutical industry has a fixed roll-pair system. This type of roll design system relies on powder gravity feed and a specially designed compression feed screw to continuously deliver powder feed stock to the fixed roll pair. Fig. 10. 

The Fitzpatrick Co. roller compactor (Fig. 20) features two feed screws in series one horizontal and the second vertical. This system is designed to transfer powder bulk into a set of cantilevered rolls positioned in the horizontal mode one is fixed, the other floats. Operator interface allows for on-line monitoring and controlling feed screw speeds, roll pressure, and roll gap. Features such as on-line help and diagnostic functions, maintenance, and calibration screens are displayed. All functions are interfaced and adjustable by PLC for process control and report generating. The machines have vacuum deaeration and roll cooling capabilities. The sizing unit is separate from the compactor and is either a rotor bar or a hammer mill. 

The newly designed equipment involved a compactor fitted with two horizontal feed screws, which featured vacuum deaeration. Specifically, the roller compactor was equipped with a conical storage hopper containing a variable speed agitator. Bulk powder was fed directly from the top of the hopper to the top of twin horizontal auger feed screws, which directly transported the powder to the nip roll area (13). Top and side views of the design features are shown in Figure 17. ... 

The difference in behavior between single- and multirow briquetting presses Above, the different behavior of wide roll compactors as compared to narrow rollers has been discussed. Roll-type briquetting presses feature even more pronounced differences if single-row designs are compared with multirow applications (i.e. two or more pockets across the face of rollers). 

---