1) Determination of the clamp angle θ For the sake of discussion, it is assumed that the material is spherical, and the crushing force of the gravity and the roller on the material is small and negligible. It is assumed that the diameter of the nominally largest spherical particle is d, the thickness of the layer is s, the diameter of the cylinder is D0, the diameter of the roller is D, and the angle θ is expressed by the angle between the material and the tangent of the contact point of the roller and the cylinder, as shown in Fig. 1. The size can be obtained according to the balance of forces. In order to make the roller mill work reliably, the clamping angle should be less than or equal to 2 times the friction angle between the material and the grinding roller and the cylinder, that is, θ ≤ 2φ, and φ is the friction angle. The coefficient of friction between the material and the roll surface is related to the state of the roll surface and the nature of the material. 2) Determination of the feed size When determining the feed size, it is considered that the thickness of the layer when the roller is ground in the pulverized material is generally less than 6 mm, which is small compared with the diameter difference (D0-D) and therefore negligible. The maximum grinding grain size of the roller mill can be calculated according to the following two formulas: d ={D0(sinθ-sinα)+D sinα}/sinθ............1 Sin {(α+β)/2}={(D0+D)/(D0-D)}sin(θ/2)............2 According to the relationship between the mill mill and the maximum grain size of the milled material, as shown in Figure 2 below. It can be seen from the figure that as the specification of the roller mill increases, the particle size of the milled material increases rapidly. For a certain size of the roller mill for grinding a certain material, the maximum particle size of the milled material is determined. of. For a roller mill with a diameter of 1 m, the maximum material of the milled material is 40 mm, but in the experimental production, it is greater than 40 mm. This may be assumed to be spherical because the actual material cannot be spherical. And with angular edges of various shapes, plus a roller mill and a unique roll channel for material rolling. Based on the above discussion, when determining the particle size of the milled material, it should also be multiplied by a factor K greater than 1, which is a parameter related to the shape of the material and the channel form of the rolled material. d = K{D0(sinθ-sinα)+D sinα}/sinθ............3 For the roller mill, as long as it can satisfy the stable feeding and the smooth running of the mill, the particle size of the grinding material can be increased as much as possible, and the purpose of reducing the number of crushing sections and saving energy is achieved. Therefore, the formula 3 for determining the particle size of the roller into the grinding material is instructive for the design and production of the roller mill. HDPE Double Wall Corrugated Pipe Hdpe Double Wall Corrugated Pipe,Large Diameter Double Wall Corrugated Pi,Double Wall Corrugated Pipe,Double Wall Corrugated Pipe For Drainage SHANDONG DONGHONG PIPE INDUSTRY CO., LTD , https://www.donghongpipe.com
How to determine the particle size of the grinding material of the roller mill?
In the dry ball (tube) mill for the cement industry, the roller mill has its unique structure and extrusion grinding process, which can fully exert its energy saving potential compared with vertical mill and roller mill. For the material layer extrusion pulverizing equipment, due to the different pulverizing mechanism and the special structure, it is necessary to increase the grain size of the grinding material under the condition of ensuring stable feeding and stable operation of the mill to reduce the number of broken sections and save. Energy consumption. The following is a discussion of the particle size of the largest milled material in the roller mill.