Features and advantages of internal mixer's mixing
Mixer mixing characteristics
The plastic compound and various compounding agents are put into a high-temperature and high-pressure Internal Mixer, and after a short time of kneading, dispersing, and mixing, the mixed rubber of the process can be obtained. The mixing process is: lifting the upper top bolt → feeding → falling on the top plug → pressing and mixing → ending the mixing → turning the lower top bolt → turning → discharging → turning back → closing the lower bolt.
The advantages of mixer mixing are: 1The mixing time is short, the production efficiency is high, the quality of the mixing rubber is good; 2The filling capacity is large, the mixing operation is high, the labor intensity is small, the operation is safe; 3The compounding agent has small loss of flying, and the pollution is small, work Site hygiene.
The disadvantages of mixer mixing are: 1 The internal heat of the internal mixer is slow, the mixing temperature is difficult to control accurately, and the temperature-sensitive rubber compound is prone to scorch phenomenon when mixing, and the cooling water consumption is large; 2 the rubber compound is irregularly shaped and must be pressed. Such as supplementary processing; 3 mixer mixing is not suitable for light-colored rubber compounds, special rubber compounds, rubber compounds with frequent varieties and temperature-sensitive rubber compounding.
Mixing machine mixing process The mixing process of the mixer has a mixing method, a second-stage I-kiln method, a feeding method and a reverse stick method. (1) Working stage of mixer mixing The tearing process of the mixer is divided into three stages of wetting, dispersing and kneading. (2) BIT value In the mixing process of the mixer, the two stages of wetting and dispersing are the wetting and dispersing. In production, judging the mixing performance of the rubber compound is often measured by the time required for the compounding agent to be uniformly dispersed by the rubber compound. Generally, the second power peak point appears on the tempering time-power map as the dispersed end time. It is called the carbon black mixing time BIT value. The smaller the BIT value, the better the compounding performance of the compound, that is, it is easy to mix. (3) Cooling and parking a. Cooling is to avoid scorching and mutual adhesion caused by high temperature of the rubber compound, generally by strong cooling to below 35 °C. b. Parking can relax the stress of rubber molecules and reduce shrinkage. The compounding agent can also be continuously dispersed, and the carbon black is further combined with the rubber to improve the physical-mechanical properties of the rubber compound.
Rapid inspection of the mixer
Controlling and guaranteeing the quality of the rubber compound is one of the key links in the production of rubber products. The rapid inspection is the rapid quality inspection of the rubber compound. The method of rapid inspection is to take one sample in each of the front, middle and back parts after the car is mixed, and measure the plasticity, vulcanization characteristics, hardness, tensile strength and pull. Elongation at break, permanent deformation, density, etc., and the measured results are compared with the specified standard values to determine whether the quality is satisfactory. The inspection methods of related projects are respectively found in the corresponding national standards.