In addition to the material ratio, kneading time and temperature during the production of the mixer, the form of the mixing tools, the layout of the mixing tools, the gap between the mixing tools and the inner wall of the tank, the shape of the bottom of the tank, the heat exchange area and thermal conductivity of the equipment that affect the grinding effect on the pigment. quality is affected.
1. The shape of the blending tool
The effect of Σ-type paddle used in pigment production is also satisfactory, but the kneading time is long and the kneading efficiency is low. The length-to-diameter ratio, cross-sectional size, working surface form and rotation of this type of blade have a great influence on the kneading effect of the pigment. The length-to-diameter ratio of stirring paddles used in pigment production is generally 2.0-2.4. Due to the large amount of wear during the pigmentation process using a mixer, a liner is generally installed on the working surface where the mixing paddle is squeezed by the material. This can not only protect the mixing paddle and extend its service life, but also prevent the mixing and mixing due to wear. When the gap between the tank walls becomes larger, it can be adjusted by welding on the lining plate to maintain the product's requirements for the equipment.
2. The center distance of the stirring paddle and the gap between the stirring paddle and the tank wall
This is a very important factor affecting the quality of pigments. For organic pigments, a gap of 3-6mm is more suitable. Too small or too large is not good. If the gap is too small, the material layer on the tank wall will be very thin, and less material will be ground between the stirring blade and the tank wall every time the stirring paddle rotates. If the gap is too large, the tank wall will easily accumulate too thick material. When the paddle rotates, the material will be ground. The buffering effect and insufficient shearing and grinding strength in the material layer all affect the kneading effect. In addition, too large a gap will cause the material layer on the tank wall to be too thick, which will also affect the heat transfer effect of the machine. The mutual extrusion and shearing of materials between the two stirring paddles is critical to whether the pigment can meet the technical requirements, so the center distance between the two paddles cannot be too large, which is generally twice the radius of rotation plus 6-15mm.
