The integral ring die of the feed pellet machine drills holes on the finished ring die, and the cross-section of the hole is mostly circular. When forming particulate fuels, the pores are relatively small in diameter and metal working is difficult. Therefore, the raw material in the hole is finely pulverized, and the friction between the raw material and the hole wall gradually increases to reach a certain molding density. When the hole diameter reaches 25mm or more, the metal processing conditions are good and can be used for processing materials. The forming cavity should be machined with feed ramps, forming angles and holding cylinders.
The sleeve-type ring die of the feed pellet machine is designed on the basis of the overall ring die, that is, the sleeve die is set in the die hole, and its purpose is to reduce the wear of the ring die and improve the ring die of the ring die. Dead hole. It is used to process rod-shaped pellet fuels with a diameter of 25 mm or more. The following technical factors should be considered in the ring die for installing the sleeve: First, consider the machining accuracy of the "mother ring" of the ring die. The advantage of installing the sleeve is that the female ring does not require special alloy materials, nor does it require strict heat treatment.
The production of feed pellet machine casting technology greatly reduces the production of metal processing. After the cavity is worn, only the sleeve is replaced without replacing the mother ring, which greatly prolongs the maintenance period. This design requires better strength of the female ring. Precision requirements are also high. The shrinkage and expansion coefficients of the material and the parent ring material are calculated and tested in detail, especially the non-metallic casing undergoes rigorous engineering tests to ensure easy installation and disassembly. It has a certain strength and hardness. The inner hole of the sleeve should have a shape to ensure molding quality, and the processing cost should be considered.
The split modular ring die of the feed pellet machine adopts a modular combined structure, and each split module can be designed and processed by a single unit. A single module is flanked by two half-molding cavities, and multiple single units are placed on the integrated fixture mold. Because each split module is individually machined, special materials can be used to treat or repair heavily worn parts for extended service intervals. Die holes or round holes after the separation modules are combined to handle lump and rod pellet fuels. The production process of the split module module is complex, the production cost is high, it is convenient for mass production, and the mold cavity is also easy to ensure the quality of the molded pellet fuel.