Applications of sand grinders

I’m looking for it too; I’ll share it once I find it

Reply to 1# yingmu841109: A grinder is an efficient grinding and dispersing device that is widely used in various industrial fields such as paints and coatings, cosmetics, food, personal care products, dyes, inks, pharmaceuticals, magnetic recording materials, ferrites, and photographic films. Overview of Sand Grinders Sand grinders, also known as bead mills, are primarily used for the wet grinding of chemical liquid products. Based on their performance characteristics, they can be classified into vertical sand grinders, basket sand grinders, horizontal sand grinders, rod sand grinders, and so on. It is mainly composed of a machine body, a grinding cylinder, a disperser, a bottom valve, a motor, and a feeding pump; the speed of material feeding is controlled by the feeding pump. The grinding media for this equipment generally include glass beads, zirconium silicate beads, zirconia beads, etc. Feed pumps generally use gear pumps, diaphragm pumps, and other pumps for transporting thick slurries. Uses of sand grinders Compared with grinding equipment such as ball mills, roller mills, and colloid mills, sand grinders offer advantages such as high production efficiency, continuous operation, low costs, and high product fineness. The process conditions vary greatly, and the requirement for fineness can be adjusted by appropriately increasing or decreasing the grinding media. Horizontal sand mill – Types of sand mills and types of beads used. The most common types include vertical sand mills, horizontal sand mills, basket sand mills, twin-cone rod sand mills, and nano-level horizontal sand mills. While vertical sand mills use ordinary glass beads with a size of 2-3/3-4 mm, the other types of sand mills utilize zirconia beads with a size of 0.8-1.2 mm. Horizontal turbine sand mill; schematic diagram of the principle of conventional sand mills. Schematic diagram of a sand mill: 1 – Water jacket ； 　　2—Typical flow pattern of the paint slurry trapped between the two dispersion discs (double annular rolling grinding action): 3—Screen ； 　　4—Paint slurry outlet after dispersion ； 　　5—Dispersion disc: 6–Mixture of paint slurry and grinding medium 7—Balancing wheel ； 　　8—Bottom valve ； 　　9—Working principle of the sanding mill at the premixed paint slurry inlet. Schematic diagram of the structure of the horizontal sanding mill. Multiple layers of disks are mounted on the rotating spindle inside the cylinder of the horizontal sanding mill. As the main shaft rotates, the grinding media, driven by the rotating disk – as shown in the schematic diagram of the grinder structure – grind the slurry inside the cylinder, reducing the size of the solid particles. The resulting fine slurry then passes through the filtering gaps or sieve pores, which are smaller than the size of the grinding media particles, and flows out. The cylinder section is equipped with cooling or heating devices to prevent the excessive heat generated by the friction between the materials, grinding media, and disks from affecting product quality, or to avoid a decrease in fluidity due to the condensation of the slurry fed in, which could impair the grinding efficiency. The grinding medium can be appropriate natural sand, or artificial glass beads with a particle size of 0.1 to 2 millimeters. When the feed particle size is less than 450 microns, the discharge particle size can be below 1 micron. This type of mill not only fine-grinds materials but also has dispersion and mixing functions, making it suitable for grinding dyes, pigments, paints, pharmaceuticals, and other suspensions or colloids. Use and Maintenance of Sanding Machines I. Commissioning 1. Carry out the preparatory work before commissioning. 　　2. Check whether all components are firmly installed. 　　3. The rotation direction of each machine should be in the direction indicated by the arrow (test the direction by jogging). 4. Check whether the cooling water is flowing smoothly. 　　5. Adjust the V-belt before restarting; adjust it again after 50 hours of operation. 　　6. Add the grinding medium from the top of the cylinder. 　　7. First, start the feed pump; only after the material has been fed and discharged from the top sieve can the main machine be started. 　　8. After a long period of parking and upon restart, the disperser often gets ‘stuck’ due to the settlement of solid particles and grinding media within the material; this problem is especially severe with viscous materials at lower temperatures, where a ‘braking’ effect becomes more pronounced. At this time, if the jog motor cannot start, manual rotation of the spindle pulley should be used as a supplement, along with the addition of a small amount of solvent capable of dissolving the material, so that the material becomes diluted and loosened before attempting to start the motor again. In short, do not force it to start to avoid damaging the electrical components and the machine. 　　9. If the vehicle is parked for an extended period, the material that has dried up on the sieve should be removed. 　　10. When cleaning the disperser, it should only be rotated gently and intermittently, as the disperser and the grinding media can easily get worn or damaged due to rapid rotation in the cleaning solution. 　　11. When using new grinding media, it should be sieved to remove impurities, fragments, and other foreign materials. 　　II. Faults 　　1. The feeding pump does not start or stops operating during use: 　　A: Is the power supply connected? ； B: Is the fuse blown? 　　2. The host cannot start or shuts down during operation: A: Is the fuse blown? ； B: Is the feed pump delivering material? ； 　　C: Is the V-belt too loose? ； D: Is the disperser stuck? 　　3. Excessive motor load: A: Is the viscosity of the material too high? ； B: Is too much grinding media loaded? ； 　　C: Are the electrical circuits functioning properly? 　　4. Feed pump does not feed: A: Is there air leakage in the pipeline? ； B: Is the feed pipe blocked? ； 　　C: Is the feed pump severely worn? ； D: Is the viscosity of the material too high? 　　5. Decreased production efficiency: A: Is there not enough grinding media? ； B: Is the disperser excessively worn out? ； 　　C: Whether the grinding media are heavily broken. Horizontal rod-type conical sand mill – Precautions for operating the sand mill: ① In the event of a long-term shutdown, check first before restarting whether the dispersion disk is stuck by the medium. If the coupling will not rotate, a pump can be used to inject the solvent. Once it has dissolved, the vertical sand mill can be started again. Do not attempt to start it forcefully to avoid damaging the friction pads. 　　②In the case of long-term parking, it is necessary to check the top sieve mesh before restarting the machine to see if there is any cured paint slurry on it. If so, it should be cleaned with a solvent to prevent blockages in the sieve, which could lead to roof collapse. 　　③Once ‘caving in’ occurs, the machine should be stopped immediately to clean the screen, a slurry collection basin should be placed, the speed of the slurry supply pump should be adjusted, and then the machine should be restarted. Otherwise, the paint slurry may penetrate the main shaft bearings, causing wear to those bearings, or it may damage the slurry feed pump. 　　④Starting is strictly prohibited when there is no paint or grinding medium in the cartridge. 　　⑤When cleaning the body with a solvent, the disperser should only be rotated slightly and intermittently to prevent wear on the components. 　　⑥When using new sand, it should be sieved to remove impurities and foreign objects. The sand used in the sanding machine should be regularly cleaned, screened, and replenished with new sand. 　　⑦The observation window should remain intact to prevent injuries caused by sand breaking off during the operation of the grinder. Latest Trends in Sand Grinders Latest trends in sand grinders: (1) Advances in grinding media separation systems: As the requirements for product fineness continue to increase, the size of the grinding media used is becoming smaller and smaller. The separation of small-sized grinding media is one of the most difficult challenges in the development of sanding machines. 　　The gap rings (with very small flow areas) and static screens used in traditional sand grinders make it difficult to separate small-sized particles! Therefore, dynamic centrifugal separation systems are being used more and more often. The centrifugal force generated by the rotating rotor drives the medium to move outward around the rotor; the center of the rotor contains slurry. By placing a separation screen at the center of the rotor, the material can pass through the gaps in the screen smoothly, thereby avoiding blockages and wear. Therefore, applying the principle of dry air classification to the separation of media in sand mills represents a technological breakthrough in the history of sand mill development! 　　(2) High-energy density pin-type sanding mills of the factory: Over the past period, several major sanding mill manufacturers at home and abroad have unilaterally believed that ； To improve product fineness (reduce particle size), it is necessary to increase the energy density of the sand mill! As a result, many sanding mills of complex structure in the form of pin-type units were developed. A: The DCP structure of the sanding mill – 1 features numerous cemented carbide pins arranged densely on both the rotor and stator. The material enters from the top, follows a winding/\nbumpy “N”-shaped path, and then exits from the bottom. The medium causes extremely severe wear on the pins, rotor, and stator, and the material is often contaminated with metals. Moreover, only expensive zirconia grinding media can be used. 　　B: The structure of the sanding machine DCP-Structure 2 is basically the same as that of Structure 1, but a cooling jacket has been added to the rotor in order to address heat dissipation issues. 　　C: The sanding machine LMZ has pins arranged only on the rotor, while cooling jackets are arranged on the stator and half of the rotor. The pin rod causes severe wear on the inner surface of the stator on the opposite side; metal contamination is inevitable! 　　(3) Horizontal centrifugal sand mill – high energy density outer ring grinding area. After years of misguided attempts to overcomplicate the design of sand mills, people have finally returned to simpler approaches! It was found that the actual grinding of the material occurs only in the grinding area with a certain energy density, while the low-energy areas merely generate heat (providing only a visual effect). High energy density regions can only appear in the outer ring area where the linear speed is highest. 　　A: The R-grinding mill feeds material radially from the outer stator; the material that passes through the outer grinding zone is discharged axially along the side of the dynamic media separation screen. 　　B: ZR- The material fed into the grinder enters the rotor via the side of the hollow shaft and reaches the outer annular grinding area; the drum (stator) of this device rotates at a different speed than the inner rotor. The media separation screen (fixed on the drum) becomes a true rotating dynamic separator, and the complex dual-rotor structure requires extremely high precision with regard to the coaxiality error of each rotating element. 　　C: SC – The material for the grinder is fed from the axial center and reaches the outer grinding area; the ground material is discharged through the sieve ring on the outer ring. The grinding track is also known as the ceramic separation ring. Although the filtration area has increased, the separation ring wears out severely and is prone to severe clogging. Working principle and dispersion effect of sand mills A sand mill is a type of horizontal, wet, continuous production ultra-fine particle disperser. The pre-mixed raw materials are fed into the grinding tank of the main unit; the tank is filled with an appropriate amount of grinding media such as glass beads. The high-speed rotation of the dispersing blades imparts sufficient kinetic energy to these grinding media, which then collide with the particles to be dispersed, generating shear forces that achieve the purpose of dispersion. Subsequently, a special separation device is used to separate the dispersed material from the grinding media and remove them. Since it requires no high level of operational skill like three-roll systems to achieve uniform and excellent quality, and allows for mass continuous production, it enables both improved quality and reduced costs. It is also suitable for dispersing highly viscous substances, and can therefore be applied in industries such as paints, inks, pharmaceuticals, food, cosmetics, and pesticides. 　　The purposes of dispersion include the following: First, to achieve a smooth surface by reducing the size of solid particles dispersed in a liquid. Increases reflectivity, gives a glossy finish, and improves coverage, as in paints, inks, color pastes, etc. 　　II. To increase the reaction rate and uniformity, thereby increasing the surface area of the particles suspended in the liquid. For example, adding granular curing agents to resins, or using powdered raw materials in chemical reactions. 　　III. Extending the settling time allows the tiny particles suspended in a liquid to remain in that state temporarily; this is useful for water-soluble pesticides, as it increases the area over which the pesticide can be spread and thus prolongs its effectiveness, or in the case of fruit juices such as papaya juice.

Great. Do you have pre-grinding equipment, ultra-fine grinding equipment, Raymond mills, ball mills, sanding machines, and vibration mills?

I’m aware of Zhongjin Lingnan’s issue – the grinding media keeps getting into the pipelines, and we’re working on resolving it right now! Our company is also considering this issue! I’m from Hulunbuir!