Particle Shaping Method

1,179,350. Rotary-tubes pelleting machines. IMPERIAL CHEMICAL INDUSTRIES Ltd. 4 Sept., 1968 [15 Sept., 1967], No. 42094/67. Heading B5A. [Also in Divisions G1 and G3] The compression load exerted by a pelleting machine is measured by a displacement transducer 34 (Fig. 1) mounted on a lever 20 in contact with the bottom die punch 24 through a roller 22, or by a strain gauge 34A on connecting rod 18, and compared with a reference value to determine if the individual pellet is acceptable. The measured force signal is recorded, or shown on a CRO, or fed to actuating mechanism which rejects faulty pellets (Fig. 2, not shown), or is used to modify the rate of feed of the powdered ingredients to maintain standard pellets (Fig. 4, not shown). The apparatus includes means for stopping the machine if the running average displacement deviates excessively from the reference value. The machine also includes limit switches 36, 37 which stop the machine if the displacement is too small or too large.