Cement clinker grinding device for cement preparation
By employing a heat conduction structure inside the ball mill steel balls and a heat exchange structure outside the mill cylinder in the cement clinker grinding device, the problems of gypsum dehydration and adhesion caused by high temperature were solved, thereby achieving stability of cement setting time and improvement of equipment efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-07
- Publication Date
- 2026-04-14
AI Technical Summary
Existing cement clinker grinding equipment is prone to gypsum dehydration and decomposition under high temperature environment, which affects cement setting time and workability. At the same time, material adhesion leads to increased equipment load and energy consumption.
By employing the heat conduction structure inside the ball mill steel balls and the heat exchange structure outside the grinding cylinder, and through air circulation cooling and coolant flow, the temperature of the material and steel balls is reduced, the contact time between the material and the grinding media is extended, and the grinding efficiency is improved.
It effectively prevents gypsum dehydration and decomposition, improves the stability of cement setting time, reduces adhesion, reduces equipment vibration and energy consumption, and improves production continuity and project quality.
Smart Images
Figure CN224114103U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cement preparation technology, and more specifically, to a cement clinker grinding device for cement preparation. Background Technology
[0002] Existing cement clinker grinding equipment is prone to continuous temperature rise during operation due to mechanical frictional heat generated during material grinding and heat accumulation from high-speed airflow. Gypsum in cement clinker, a key component regulating cement setting time, undergoes dehydration and decomposition at high temperatures (above 80°C), losing its retarding effect and significantly shortening the cement setting time, directly impacting the workability and quality of subsequent concrete. Furthermore, high temperatures cause the ground material to adhere due to increased surface activity, forming a thick adhesive layer on the surfaces of grinding media, liners, and classifiers. This not only increases equipment load and reduces grinding efficiency but also leads to increased equipment vibration and energy consumption. Statistics show that adhesion caused by high temperatures can reduce grinding system capacity by 15%-20% and significantly increase equipment maintenance costs. Therefore, we propose a cement clinker grinding device for cement preparation. Utility Model Content
[0003] The purpose of this utility model is to overcome the shortcomings of the existing technology, adapt to the needs of reality, and provide a cement clinker grinding device for cement preparation, so as to solve the technical problem that high temperature dehydration easily occurs during the current grinding of gypsum clinker.
[0004] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a cement clinker grinding device for cement preparation, including a ball mill frame, a drive motor installed on one side of the ball mill frame, a gearbox connected to the output end of the drive motor via a transmission belt, a grinding cylinder fixed to the output end of the gearbox, free end rollers provided at both ends of the grinding cylinder, the two ends of the grinding cylinder being respectively designated as the feed end and the discharge end, a plurality of grinding steel balls being arranged inside the grinding cylinder, the grinding steel balls having a heat conduction structure inside, the heat conduction structure including a hollow cavity opened at the center of the grinding steel balls, and a heat exchange structure being provided on the outer wall of the grinding cylinder.
[0005] Preferably, the heat conduction structure includes a central connection point, and multiple guide vanes are provided on the outer periphery of the central connection point, and the hollow cavity is filled with air.
[0006] Preferably, the guide vane is narrower at one end near the center of the ball milling steel ball and connected to the center connection point, and the guide vane gradually widens towards the inner wall of the outer shell and is fixed to the inner wall of the ball milling steel ball.
[0007] Preferably, the heat exchange structure includes a spiral guide track, which is a continuous spiral protrusion structure. The pitch of the spiral gradually decreases from the feed end to the discharge end of the grinding cylinder, and the interior of the spiral guide track is a hollow structure.
[0008] Preferably, the heat exchange structure further includes a heat exchange shell, which is installed on the side wall of the grinding cylinder. The heat exchange shell is connected to the spiral guide rail. Coolant is filled between the heat exchange shell and the hollow spiral guide rail. A sealing cover is installed at the opening of the heat exchange shell, and multiple heat exchange fins are installed on the sealing cover.
[0009] Preferably, the ball milling steel ball is composed of two hemispheres, which are threaded together and fixed by bolts.
[0010] Compared with the prior art, the beneficial effects of this utility model are:
[0011] 1. This utility model achieves cooling of both the material and the steel balls themselves through the internal heat conduction structure of the ball mill steel balls. When the steel balls move inside the ball mill, the internal air circulates under the action of the guide vanes, absorbing the heat generated by the friction between the material and the steel balls and dissipating it. This avoids the dehydration and decomposition of gypsum due to excessive temperature, ensures the stability of cement setting time, and thus improves the construction performance and project quality of subsequent concrete, solving the problem of high-temperature dehydration that easily occurs during the grinding of gypsum clinker.
[0012] 2. This utility model also uses high-strength, high-wear-resistant alloy steel material for the grinding balls, which can withstand huge impact and friction, ensuring stability during long-term grinding. At the same time, the special design of the spiral guide track in the heat exchange structure of the outer wall of the grinding cylinder increases the movement path of the material in the cylinder, prolongs the contact time between the material and the grinding media and grinding balls, improves grinding efficiency, avoids local accumulation of material, and further solves the problem of high-temperature dehydration that easily occurs when grinding gypsum clinker.
[0013] 3. This utility model also reduces the adhesion phenomenon of materials after grinding due to the enhanced surface activity through effective cooling measures. It reduces the adhesion of materials on the surfaces of grinding media, liners, classifiers and other equipment, reduces equipment load, reduces equipment vibration and energy consumption, and avoids the reduction of grinding system capacity and the increase of equipment maintenance costs caused by adhesion.
[0014] 4. This utility model also uses a spiral guide track in the heat exchange structure that is hollow and filled with coolant. The rotation of the grinding cylinder causes the coolant to flow up and down, contacting the gypsum for cooling. At the same time, the heat exchange fins can cool the flowing coolant, which facilitates continuous use of the device and improves the continuity and stability of production. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structure of this utility model;
[0016] Figure 2 This is a schematic diagram of the internal structure of the grinding cylinder in this utility model;
[0017] Figure 3 This is a connection diagram of the heat exchange structure in this utility model;
[0018] Figure 4 This is a schematic diagram showing the disassembled structure of the heat exchange structure in this utility model;
[0019] Figure 5 This is a schematic diagram of the internal structure of the steel balls in the ball mill of this utility model;
[0020] Figure 6 This is a schematic diagram of the heat conduction structure in this utility model.
[0021] The following are the labels in the diagram: 1. Ball mill frame; 2. Drive motor; 3. Gearbox; 4. Grinding cylinder; 5. Free end roller; 6. Grinding balls; 7. Heat conduction structure; 8. Heat exchange structure; 701. Hollow cavity; 702. Center connection point; 703. Guide vane; 801. Spiral guide track; 802. Heat exchange shell; 803. Sealing cover plate; 804. Heat exchange fins. Detailed Implementation
[0022] like Figures 1 to 6As shown, this utility model relates to a cement clinker grinding device for cement preparation, including a ball mill frame 1. A drive motor 2 is installed on one side of the ball mill frame 1. The output end of the drive motor 2 is connected to a gearbox 3 via a transmission belt. A grinding cylinder 4 is fixed at the output end of the gearbox 3. Free end rollers 5 are provided at both ends of the grinding cylinder 4. The two ends of the grinding cylinder 4 are respectively designated as the feed end and the discharge end. Multiple grinding steel balls 6 are arranged inside the grinding cylinder 4. Each grinding steel ball 6 is composed of two hemispheres, which are threaded together and fixed with bolts. The connection between the two hemispheres is sealed. The grinding steel balls 6 are made of high-strength, high-wear-resistant alloy steel, such as chromium-molybdenum alloy steel. This material has good hardness and toughness and can withstand huge impact and friction during long-term grinding without easily breaking. To ensure the service life of the hollow steel balls under complex working conditions of the ball mill, the ball mill steel ball 6 has an internal heat conduction structure 7. The heat conduction structure 7 includes a hollow cavity 701 located at the center of the ball mill steel ball 6 and a central connection point 702. Multiple guide vanes 703 are provided on the outer periphery of the central connection point 702. The hollow cavity 701 is filled with air. The guide vanes 703 are narrower at the end near the center of the ball mill steel ball 6 and connected to the central connection point 702. The guide vanes 703 gradually widen towards the inner wall of the outer shell and are fixed to the inner wall of the ball mill steel ball 6 to better guide the airflow. The number of guide vanes 703 is determined according to the size of the steel ball, generally between six and ten. For smaller diameter steel balls, six to eight guide vanes 703 are set; for larger diameter steel balls, eight to ten vanes can be set.
[0023] The thickness of the outer shell of the grinding steel ball 6 is carefully designed to balance the overall strength and mass of the steel ball as well as the space of the hollow cavity 701. Generally, the outer shell thickness accounts for one-quarter to one-third of the radius of the entire steel ball. For example, for a hollow steel ball with a diameter of fifty millimeters, the outer shell thickness is about eight to twelve millimeters. This ensures that the steel ball has sufficient strength and inertial impact force during grinding, while also providing reasonable space for the internal hollow structure and the guide vanes 703 to achieve the cooling function. The guide vanes 703 are fan-shaped and extend radially outward from the center of the grinding steel ball 6 to the inner wall of the outer shell of the grinding steel ball 6. The fan-shaped arc is about sixty to ninety degrees.
[0024] The hollow inner cavity is a regular spherical space, concentrically set with the outer shell of the steel ball. Its size is adjusted according to the overall size of the steel ball and the actual cooling requirements, generally accounting for 30% to 50% of the total volume of the steel ball. For example, for the steel ball with a diameter of 50 mm, the diameter of the hollow inner cavity is about 30 to 40 mm. This hollow space provides a place for air flow and is the basis for realizing internal air circulation and cooling. In actual use, the number and size of the grinding steel balls 6 can be selected according to the required heat dissipation.
[0025] Working principle: When the hollow steel balls rotate, roll and collide with each other in the ball mill, the internal air circulates around the hub under the action of the guide vanes 703. During the contact and collision with the material, the air absorbs the heat generated by the friction between the material and the steel balls. The heat is transferred and diffused in the hollow cavity through the circulation. Some of the heat is dissipated through the outer shell of the steel balls, thereby cooling the material and the steel balls themselves. At the same time, the steel balls, which are lighter in weight, can still effectively perform grinding work due to inertia.
[0026] The heat conduction principle described above is as follows: When the steel balls rotate inside the ball mill, the outer shell of the steel balls frequently collides and rubs with the material. The surface temperature of the outer shell rises due to frictional heat. Since the outer shell of the steel balls is made of alloy steel with good thermal conductivity, the heat will be quickly transferred from the outer shell surface to the entire outer shell. The air in the hollow inner cavity is in direct contact with the inner wall of the steel ball outer shell. According to the principle of heat conduction, the heat is transferred from the inner wall of the steel ball outer shell with a higher temperature to the relatively lower temperature air, realizing the transfer of heat from the friction point between the material and the steel balls to the air in the hollow inner cavity.
[0027] It is worth mentioning that during the operation of the ball mill, the hollow steel balls are constantly moving, and the air inside them forms a circulating airflow under the action of the guide vanes 703. This keeps the air in the hollow cavity in a flowing state. The heat exchange between the air and the inner wall of the steel ball shell involves not only heat conduction but also convective heat exchange. The flowing air can more quickly and effectively transfer the heat absorbed by the inner wall of the shell to all parts of the hollow cavity, enhancing the heat transfer effect in the hollow cavity and further promoting the transfer of heat from the friction point between the material and the steel ball to the hollow cavity.
[0028] To enhance the cooling effect, a heat exchange structure 8 is provided on the outer wall of the grinding cylinder 4. The heat exchange structure 8 includes a spiral guide rail 801, which is made of wear-resistant alloy steel. Its surface is designed with a continuous spiral protrusion structure. The pitch of the spiral gradually decreases from the feed end to the discharge end of the cylinder, and the helix angle of the spiral is larger near the feed end and gradually decreases towards the discharge end. This design allows the material to move along the spiral line in the cylinder, increasing the movement path of the material in the cylinder and prolonging the contact time between the material and the grinding media and the grinding balls 6, thereby improving the grinding efficiency. At the same time, the spiral guiding effect allows the material to move more orderly from the feed end to the discharge end, avoiding local accumulation of material.
[0029] The spiral guide rail 801 has a hollow structure inside. The heat exchange structure 8 also includes a heat exchange shell 802, which is installed on the side wall of the grinding cylinder 4. The heat exchange shell 802 is connected to the spiral guide rail 801. Coolant is filled between the hollow space of the heat exchange shell 802 and the spiral guide rail 801. A sealing cover plate 803 is installed at the opening of the heat exchange shell 802. Multiple heat exchange fins 804 are installed on the sealing cover plate 803.
[0030] Working principle: The spiral guide rail 801 extends the contact time and improves the crushing effect. Its hollow interior, filled with coolant, combined with the rotation of the grinding cylinder 4, allows the coolant to flow up and down inside. The contact between the spiral guide rail 801 and the gypsum can cool it down. At the same time, the heat exchange fins 804 can cool the flowing coolant, facilitating continuous use.
[0031] The embodiments disclosed herein are preferred embodiments, but are not limited thereto. Those skilled in the art can readily grasp the spirit of this utility model based on the above embodiments and make different extensions and variations. However, as long as they do not depart from the spirit of this utility model, they are all within the protection scope of this utility model.
Claims
1. A cement clinker grinding device for cement production, characterized in that, The device includes a ball mill frame (1), a drive motor (2) is installed on one side of the ball mill frame (1), a gearbox (3) is connected to the output end of the drive motor (2) via a transmission belt, a grinding cylinder (4) is fixed to the output end of the gearbox (3), a free end roller (5) is provided at both ends of the grinding cylinder (4), the two ends of the grinding cylinder (4) are respectively set as the feed end and the discharge end, a plurality of grinding steel balls (6) are provided inside the grinding cylinder (4), the grinding steel balls (6) have a heat conduction structure (7) inside, the heat conduction structure (7) includes a hollow cavity (701) opened in the center of the grinding steel balls (6), and a heat exchange structure (8) is also provided on the outer wall of the grinding cylinder (4).
2. A cement clinker grinding device for cement production according to claim 1, characterized in that, The heat conduction structure (7) includes a central connection point (702), and a plurality of guide vanes (703) are provided on the outer periphery of the central connection point (702). The hollow cavity (701) is filled with air.
3. A cement clinker grinding device for cement production according to claim 2, characterized in that, The guide vane (703) is narrower at one end near the center of the ball mill steel ball (6) and connected to the center connection point (702). The guide vane (703) gradually widens towards the inner wall of the outer shell and is fixed to the inner wall of the ball mill steel ball (6).
4. A cement clinker grinding device for cement preparation according to claim 3, characterized in that, The heat exchange structure (8) includes a spiral guide track (801), which is a continuous spiral protrusion structure. The pitch of the spiral gradually decreases from the feed end to the discharge end of the grinding cylinder (4). The spiral guide track (801) is hollow inside.
5. A cement clinker grinding device for cement preparation according to claim 4, characterized in that, The heat exchange structure (8) further includes a heat exchange shell (802), which is installed on the side wall of the grinding cylinder (4). The heat exchange shell (802) is connected to the spiral guide rail (801). Coolant is filled between the heat exchange shell (802) and the spiral guide rail (801). A sealing cover plate (803) is installed on the opening of the heat exchange shell (802), and multiple heat exchange fins (804) are installed on the sealing cover plate (803).
6. A cement clinker grinding device for cement preparation according to claim 5, characterized in that, The ball milling steel ball (6) is composed of two hemispheres, which are connected by threads and fixed by bolts.