5L Metal Internal Mixer

Veblen Technology specializes in the production of 5L metal internal mixers and 5-liter metal powder internal mixers. The 5L metal internal mixer is specifically designed for the raw material mixing stage in the metal powder injection molding process. The primary raw materials include: stainless steel powder, iron powder, titanium alloy powder, tungsten alloy powder, copper alloy powder, etc. The 5L metal internal mixer has gained widespread favor among MIM customers due to its excellent dispersion effect and highly wear-resistant chamber. For more information on the 5L metal internal mixer and 5-liter metal powder internal mixer, please feel free to call for consultation.
II: Parameters of the 5L Metal Internal Mixer

Mixing Capacity-------------------------------5L
Drive Motor-------------------------------7.5KW
Tilting Motor-------------------------------0.55KW
Tilting Angle-------------------------------110°
Main Dust Collector----------------------------200W
Output--------------------------------5-8KG
Rotor Speed------------------------------33 r/min (variable frequency speed regulation available upon request)
Dimensions (H*W*L)-----------------------1900*1000*2000MM
Machine Weight-----------------------------------1200KG

III: Working Principle of the 5L Metal Internal Mixer

During operation, the two rotors rotate relative to each other, gripping the material from the feed port and drawing it into the roll gap, where it is subjected to squeezing and shearing by the rotors. After passing through the roll gap, the material hits the sharp edge of the lower plunger and is divided into two parts, which return to the area above the roll gap along the gaps between the front and rear chamber walls and the rotors. As the material flows around the rotors, it is subjected to shearing and friction at every point, causing the temperature of the compound to rise sharply and its viscosity to decrease. This enhances the wetting of the rubber on the surface of the additives, ensuring full contact between the rubber and the additive surfaces. Additive agglomerates pass through the gaps between the rotors, between the rotors and the upper and lower plungers, and between the rotors and the internal mixer chamber walls along with the rubber, where they are broken down by shearing and enveloped by the stretched and deformed rubber, stabilizing in a broken state. Meanwhile, the ridges on the rotors cause the rubber to move axially along the rotors, providing a mixing and stirring effect that ensures uniform dispersion of the additives in the rubber. The repeated shearing and breaking of the additives, along with the repeated deformation and recovery of the rubber and the continuous stirring by the rotor ridges, result in uniform dispersion of the additives in the rubber and achieve a certain degree of dispersion. Due to the significantly greater shearing action and higher mixing temperature compared to open mills, the efficiency of the internal mixer is much higher than that of open mills.

IV: Operating Procedures for the 5L Metal Internal Mixer
1. Calculate the batch mixing quantity and actual formula based on the capacity of the internal mixer chamber and an appropriate fill factor (0.6–0.7);
2. Accurately weigh the various raw materials according to the actual formula, and arrange the raw rubber, minor ingredients (ZnO, SA, accelerators, antioxidants, solid softeners, etc.), reinforcing agents or fillers, liquid softeners, and sulfur separately on the storage rack in order;
3. Turn on the power switch and heating switch of the internal mixer to preheat it, while checking whether the air pressure, water pressure, and voltage meet the process requirements, and whether the temperature measurement system, timing device, and power system indicators and records are normal;
4. After preheating the internal mixer, allow it to stabilize for a period before starting mixing;
5. Raise the upper plunger, feed the raw rubber cut into small pieces into the internal mixer through the feed port, lower the upper plunger, and mix for 1 minute;
6. Raise the upper plunger, add the minor ingredients, lower the upper plunger, and mix for 1.5 minutes;
7. Raise the upper plunger, add carbon black or filler, lower the upper plunger, and mix for 3 minutes;
8. Raise the upper plunger, add liquid softeners, lower the upper plunger, and mix for 1.5 minutes;
9. Discharge the rubber, measure the temperature of the compound with a thermocouple thermometer, and record the initial chamber temperature, chamber temperature at the end of mixing, discharge temperature, maximum power, and rotor speed;
10. Adjust the roll gap of the open mill to 3.8 mm, turn on the power switch to start the open mill, open the circulating water valve, then feed the discharged rubber from the internal mixer onto the open mill for banding. When the rubber temperature drops below 110°C, add sulfur, cut the rubber from both sides twice each, and once the sulfur is fully incorporated and the rubber surface is smooth, cut off the rubber;
11. Adjust the open mill roll gap to 0.5 mm, feed the rubber for thin-pass mixing, make triangle folds, thin-pass five times, then adjust the roll gap to about 2.4 mm, feed the rubber for banding, and once the surface is smooth and free of bubbles, sheet off the rubber. Weigh the total mass of the rubber, place it on a flat, clean metal surface to cool to room temperature, attach a label indicating the compound formula number and mixing date, and allow it to rest for future use.
For each batch mixing process test report of the internal mixer, record: starting mixing temperature, mixing time, rotor speed, upper plunger pressure, discharge temperature, power consumption, difference between the mass of the mixed compound and the total mass of raw materials, and the type of internal mixer.
Note: When starting mixing experiments, first mix a batch of rubber with the same formula as the test compound to adjust the working state of the internal mixer before正式 mixing; for the same batch of mixed compound, the control conditions and mixing time of the internal mixer should remain consistent.