The pellet mill primarily consists of feeding, mixing, pelletizing, drive, and lubrication systems. The operational process begins with compound powder-requiring a moisture content of no more than 15%-entering the feed auger from the hopper. The material flow rate is regulated by adjusting the speed of a variable-speed motor. The material then enters the mixer, where it is conditioned through agitation by mixing paddles and the injection of steam. If molasses or fats are required, they are introduced into the mixing chamber to be conditioned alongside the steam; fat content is generally limited to a maximum of 3% to ensure proper pellet formation. After conditioning, the compound powder reaches a temperature of 64–85°C and a moisture content of 14–16%. The material then passes through a chute-equipped with an optional magnetic separator to remove iron impurities-before entering the compression chamber for pelletization.
Feeder
The feeder comprises a variable-speed motor, a speed reducer, an auger housing, and an auger shaft.
The variable-speed motor consists of a three-phase asynchronous AC motor, an eddy-current clutch, and a tachogenerator. It operates in conjunction with a JZT controller; the output speed is adjusted using a JDIA-type electromagnetic speed-regulating motor controller.
Speed Reducer
The feeder utilizes a cycloidal pin-wheel reducer with a reduction ratio of 1:10. It is directly coupled to the variable-speed motor to reduce speed, maintaining the effective rotational speed of the feed auger between 12 and 120 rpm.
Feed Auger
The feed auger consists of an auger housing, an auger shaft, and mounted bearings. The auger serves to transport material; its rotational speed-and thus the feed rate-is adjustable to achieve the rated motor current and production output. The auger shaft can be withdrawn from the right end of the housing for cleaning and maintenance.
