Release time:

2020-10-22

1. Calculate the single batch amount of rubber and the actual formula according to the capacity of the internal mixer chamber and the appropriate filling factor (0.6～0.7); 2. According to the actual formula, accurately weigh the amount of various raw materials in the formula. Place the raw rubber, small materials (ZnO, SA, accelerator, antioxidant, solid softener, etc.), reinforcing agent or filler, liquid softener, and sulfur separately and arrange them in order on the shelf; 3. Turn on the power switch and heating switch of the internal mixer for preheating. At the same time, check whether the air pressure, water pressure, and voltage meet the process requirements, and check whether the temperature measurement system, timing device, power system indication, and record are normal; 4. After the internal mixer is preheated, stabilize it for a period of time and prepare for rubber mixing; 5. Lift the upper top plug, put the raw rubber cut into small pieces into the internal mixer from the feeding port, lower the upper top plug, and mix the rubber for 1 min; 6. Lift the upper top plug, add small materials, lower the upper top plug and mix for 1.5 min; 7. Lift the upper top plug, add carbon black or filler, lower the upper top plug and mix for 3 min; 8. Lift the upper top plug, add liquid softener, lower the upper top plug and mix for 1.5 min; 9. Discharge the rubber, measure the temperature of the rubber with a thermocouple thermometer, and record the initial temperature of the mixing chamber, the temperature of the mixing chamber at the end of mixing, the discharge temperature, the maximum power, and the speed of the rotor; 10. Adjust the roll gap of the internal mixer to 3.8 mm, turn on the power switch to make the open mill run, open the circulating water valve, then put the rubber discharged from the internal mixer onto the open mill to wrap the roll. After the rubber temperature drops to below 110 ℃, add sulfur, cut twice with the left and right knives, wait until the sulfur is completely absorbed, the surface of the rubber is relatively smooth, and then cut off the rubber. 11. Adjust the roll gap of the internal mixer to 0.5 mm, put in the rubber for thin rolling, make a triangle package, thin roll 5 times, adjust the roll gap to about 2.4 mm, put in the rubber for roll wrapping. After the surface is smooth and bubble-free, take off the sheet, weigh the total mass of the rubber, place it on a flat, clean metal surface and cool to room temperature, paste a label indicating the rubber formula number and mixing date, and store it for later use.