The quenching and tempering has a great influence on the PDI of the pellet feed. After the tempering of the raw material, the particles are tightly bound, the surface defects of the particles are less, and the fine powder is not easily produced. The hardness of the pellet after cooling is high, and it is not easy to be broken during transportation. . Factors affecting the quality of quenching and tempering mainly include quenching and tempering temperature, quenching and tempering time and tempering moisture. sXc China Feed Industry Information Network - based on feed, serving animal husbandry

Different feed varieties have different requirements for quenching and tempering temperature, quenching time and moisture. The quenching and tempering temperature of general livestock and poultry materials is between 70~85 °C, the quenching and tempering time is 20~40 s, the moisture after quenching and tempering is 14%~16%; the quenching and tempering temperature of aquatic feed is 85~95 °C, and the quenching and tempering time is 40~ 120 s, the moisture after conditioning is 15%~18%; for some feeds containing heat sensitive raw materials (sucrose, glucose, skimmed milk powder, whey powder, etc.), the temperature is generally controlled within 60 °C, otherwise coking will occur, blocking the ring Die, granulation is difficult. sXc China Feed Industry Information Network - based on feed, serving animal husbandry

Quenching and tempering requires high quality saturated steam, which has high requirements for boilers and piping systems. The boiler shall be able to provide stable steam with a pressure between 0.7 and 1.0 MPa, then pass through the high-pressure conveying pipeline, enter the steam distribution package in the workshop, and finally depressurize to 0.15~0.4 MPa through the pressure reducing valve before entering the conditioner. In the pipeline transportation process, the condensed water in the steam is discharged by reasonably arranging a certain number of traps to ensure that the steam entering the conditioner is saturated steam. The pressure reducing valve should be installed 4.5 to 10 m away from the conditioner, not too close to the conditioner to ensure sufficient space and time for the steam to stabilize after decompression. The manual shut-off valve or automatic control valve that controls the entry into the conditioner should be manufactured by a manufacturer with guaranteed quality to ensure a linear change in the flow rate when adjusting the steam volume. sXc China Feed Industry Information Network - based on feed, serving animal husbandry