Vibration reduction structure for coal mill base and coal mill equipment

Abstract

The utility model belongs to the technical field of vibration treatment of mechanical equipment, and particularly relates to a vibration reduction structure for a coal mill base and coal mill equipment. A vibration reduction structure for a coal mill base comprises an anchoring foundation used for being arranged in a ground area on the periphery of the coal mill base; the anchoring foundation provides a rigid bearing platform and is used for receiving and dispersing vibration energy from the coal mill base; the at least one transition bearing part is connected with the anchoring foundation in a fastening manner; a leveling cushion layer is further arranged between the rigid bearing platform and the transition bearing piece. And at least one group of connection reinforcing members, two ends of the connection reinforcing members are respectively and rigidly connected with the transition bearing member and the coal mill base, and the connection reinforcing members are used for effectively transmitting vibration energy from the coal mill base to the transition bearing member. And the stress distribution of the connecting area of the coal mill base and the transition bearing piece is balanced.

Description

Technical Field

[0001] This utility model belongs to the field of vibration control technology for mechanical equipment, and particularly relates to a vibration reduction structure for a coal mill base and a coal mill equipment. Background Technology

[0002] In modern industrial production, especially in thermal power generation, coal mills are key equipment for preparing pulverized coal, and their stable and efficient operation directly affects the safety and economy of the entire generator unit. Medium-speed coal mills are widely used due to their high grinding efficiency and wide adaptability to various coal types. During long-term high-load operation, coal mills generate complex dynamic loads, mainly composed of unbalanced forces from rotating components, impact forces during the grinding process, and pulsating forces generated by material flow. These dynamic loads are transmitted to the foundation structure beneath the mill base. As the core component supporting the weight of the entire coal mill and transmitting various forces, the structural rigidity of the mill base and the stability of its connection to the foundation are crucial.

[0003] However, in actual operation, excessive vibration of the medium-speed coal mill base is a common and challenging technical problem. Vibration not only exacerbates the wear of equipment parts and shortens the equipment's service life, but can also lead to loosening of connecting bolts, structural fatigue damage, and even sudden shutdown accidents, seriously affecting the production continuity and economic benefits of power generation companies. The causes of base vibration are varied, including insufficient equipment installation precision, uneven foundation settlement due to long-term operation, insufficient design stiffness margin of the base itself, or loose anchor bolts. Traditional solutions to this type of vibration problem often involve large-scale shutdown, overhaul, and modification of the base and its foundation. These traditional solutions typically involve lifting the entire base, partially or completely demolishing the original concrete foundation, then recasting a new concrete foundation, and reinstalling the base, secondary grouting, and precision leveling after the foundation has cured to its strength.

[0004] While the aforementioned traditional base modification solutions can address the vibration problem of the mill base to some extent, their inherent drawbacks are becoming increasingly apparent. First, these solutions have extremely long construction cycles, typically requiring weeks or even longer, leading to prolonged unit downtime and significant power generation losses. Second, the construction process is complex, involving high-altitude operations with large lifting equipment and deep foundation pit excavation, posing high safety risks such as falls from heights, crushing by heavy objects, and foundation pit collapse. Third, material consumption is high, labor costs are high, and overall maintenance costs are expensive. Furthermore, large-scale demolition and reconstruction work can adversely affect the surrounding environment. Therefore, existing technologies for addressing the vibration problem of medium-speed coal mill bases generally face the dilemmas of poor construction safety, long downtime, high economic costs, and the inability to fundamentally and quickly improve the rigidity of the structural system, urgently requiring a more efficient, safe, and economical solution. Utility Model Content

[0005] The purpose of this utility model is to solve the above-mentioned technical problems and provide a vibration reduction structure for a coal mill base and a coal mill equipment.

[0006] A vibration damping structure for a coal mill base, the vibration damping structure comprising:

[0007] An anchoring foundation is provided in the ground area around the outer periphery of the coal mill base; the anchoring foundation provides a rigid bearing platform and is used to receive and disperse vibration energy from the coal mill base.

[0008] At least one transition bearing member is provided, which is fastened to the anchoring foundation; a leveling pad is also provided between the rigid bearing platform and the transition bearing member;

[0009] And at least one set of connecting reinforcement members, the two ends of which are rigidly connected to the transition bearing member and the coal mill base, respectively. The connecting reinforcement members are used to effectively transfer the vibration energy originating from the coal mill base to the transition bearing member and to balance the stress distribution in the connection area between the coal mill base and the transition bearing member.

[0010] Furthermore, the anchoring foundation includes: a pit or trench excavated in the ground area;

[0011] The concrete substrate poured into the pit, the top surface of which is leveled to form the rigid load-bearing platform; and

[0012] Anchor bolts, the lower end of which is anchored inside the concrete matrix, and the upper end of which is fastened to the transition bearing member.

[0013] Furthermore, the leveling pad is one or more sets of metal pads with adjustable thickness, which are used to adjust the levelness of the transition bearing and the uniformity of the bottom support.

[0014] Furthermore, the transition bearing member is a steel structure platform with reinforcing ribs, which are used to improve the overall bending and torsional stiffness of the steel structure platform; the steel structure platform is provided with through holes corresponding to the anchor bolts, and the anchor bolts pass through the through holes and are fastened to the steel structure platform.

[0015] Furthermore, the connecting reinforcement is a triangular reinforcing plate, and the two sides of the triangular reinforcing plate are rigidly connected to the top surface of the transition bearing member and the side wall of the coal mill base, respectively.

[0016] Furthermore, the concrete matrix is ​​also equipped with a steel cage consisting of multiple layers of bidirectional threaded steel bars.

[0017] Furthermore, the lower anchoring hole of the anchor bolt is filled with grout.

[0018] Furthermore, the outer shell of the coal mill base is rigidly connected with a square reinforcing plate.

[0019] A coal mill device includes the vibration damping structure as described above.

[0020] The beneficial effects of this utility model are:

[0021] This utility model provides a vibration reduction structure for a coal mill base. By setting an anchor foundation on the outer periphery of the coal mill base to form a rigid bearing platform, and then rigidly connecting the coal mill base to the anchor foundation through transition bearing components and connecting reinforcement components, it can effectively solve the problems of long construction period, high safety risk, high cost and difficulty in quickly improving the overall rigidity of the structure in the existing coal mill base vibration control schemes. This structure avoids the demolition of the original coal mill base and the large-scale demolition and reconstruction of the original foundation, significantly shortening the construction cycle and reducing equipment downtime, thereby reducing production losses. At the same time, by reducing high-risk procedures such as high-altitude operations and deep foundation excavation, the safety of the construction process is greatly improved. In addition, by adding an independent, high-rigidity anchoring foundation to the outside of the original base, and using transition bearing components and connecting reinforcements to effectively transfer and disperse vibration energy to the new anchoring system, not only is the rigidity and stability of the entire support system enhanced and vibration suppressed, but stress distribution is also optimized, extending the service life of the equipment. Moreover, the overall implementation cost is significantly reduced compared to traditional solutions, providing an efficient, safe, and economical technical approach for vibration control of coal mill bases. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a vibration damping structure;

[0023] Figure 2 This is a schematic diagram of a rigid connection for connecting reinforcement components;

[0024] Figure 3 A schematic diagram showing the relationship between the coal mill base and the pit;

[0025] Figure 4 A schematic diagram showing the relationship between the pit and the anchor bolts;

[0026] Figure 5 This is a schematic diagram showing the connection between the transition bearing component and the anchor bolts;

[0027] Figure 6 A schematic diagram showing the connection between the outer shell of the coal mill base and the square reinforcing plate;

[0028] Reference numerals: 1. Vibration damping structure; 10. Anchoring foundation; 101. Pit; 102. Concrete substrate; 103. Rigid bearing platform; 104. Anchor bolt; 105. Grouting material; 20. Transition bearing component; 30. Leveling pad; 40. Connecting reinforcement; 50. Coal mill base; 501. Shell; 60. Square reinforcing plate. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this utility model. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0030] In the following description, references to "some embodiments" refer to a subset of all possible embodiments; however, it is understood that "some embodiments" may be the same or different subsets of all possible embodiments and may be combined with each other without conflict. Unless otherwise defined, all technical and scientific terms used in the embodiments of this utility model have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of this utility model belong. The terminology used in the embodiments of this utility model is for the purpose of describing the embodiments of this utility model only and is not intended to limit the utility model.

[0031] Those skilled in the art should understand that, in the following description of the embodiments of this utility model, the sequence of numbers does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this utility model.

[0032] The terminology used in the embodiments of this utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The singular forms "a" and "the" as used in the embodiments of this utility model and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0033] This embodiment provides a vibration damping structure 1 for a coal mill base 50, such as... Figures 1-6 As shown, the vibration damping structure 1 includes:

[0034] Anchor foundation 10 is provided in the ground area around the outer periphery of the coal mill base 50; anchor foundation 10 provides a rigid bearing platform 103 and is used to receive and disperse vibration energy from the coal mill base 50.

[0035] At least one transition bearing member 20 is fastened to the anchoring foundation 10; a leveling pad 30 is also provided between the rigid bearing platform 103 and the transition bearing member 20.

[0036] And at least one set of connecting reinforcement members 40, with the two ends of the connecting reinforcement members 40 rigidly connected to the transition bearing member 20 and the coal mill base 50 respectively. The connecting reinforcement members 40 are used to effectively transfer the vibration energy originating from the coal mill base 50 to the transition bearing member 20 and to balance the stress distribution in the connection area between the coal mill base 50 and the transition bearing member 20.

[0037] In one specific embodiment, a vibration damping structure 1 is provided for a coal mill base 50, which is, for example, the core support structure of a medium-speed coal mill in a thermal power plant. The vibration damping structure 1 includes the following parts:

[0038] Anchor Foundation 10: This anchor foundation 10 is located on the ground around the outer periphery of the coal mill base 50. Specifically, firstly, the ground is excavated outwards at a predetermined distance (within a range of 620mm) along the outer edge of the coal mill base 50 (medium-speed mill body), forming a pit 101 that surrounds or partially surrounds the coal mill base 50. The pit 101 is 100mm deep. Then, holes (Φ150×800mm holes) for installing anchor bolts 104 are drilled within this pit 101. Anchor bolts 104 (M36×900mm, pre-embedded depth 800mm, made of 8.8 grade carbon steel) are installed and initially fixed using high-strength grout 105 (H-40 high-strength grout 105). Then, concrete (C40 concrete) is poured into the pit 101 to form a solid concrete base 102. The top surface of the concrete substrate 102 is leveled (e.g., by smoothing or subsequent grinding) to form a rigid load-bearing platform 103. This anchored foundation 10, through its mass and close connection with the ground, can effectively receive and disperse the vibrational energy transmitted from the coal mill base 50.

[0039] At least one transition support 20: The transition support 20 is preferably a steel platform (30mm thick, customized to fit a 620mm extension of the machine base). The bottom surface of this platform is supported on the rigid support platform 103 of the anchor foundation 10 by a leveling pad 30. The leveling pad 30 can specifically be one or more sets of metal shims. By adjusting the thickness and number of shims, the levelness of the platform can be precisely adjusted to ensure uniform contact between its bottom and the support platform. The platform is securely connected to the anchor foundation 10 by anchor bolts 104 passing through its pre-drilled holes.

[0040] And at least one set of connecting reinforcements 40: the connecting reinforcements 40 are preferably steel stiffeners, preferably triangular stiffeners. These stiffeners are rigidly connected at both ends by welding or other means, with one end connected to the upper surface of the transition bearing member 20 (platform) and the other end connected to the bottom of the side wall of the coal mill base 50. More specifically, one side of the triangular stiffener is welded to the platform, and the other right-angled side is welded to the coal mill base 50, with the hypotenuse providing support. This connection method ensures that the vibration energy originating from the coal mill base 50 can be effectively transferred to the transition bearing member 20 (platform), and further transferred to the anchoring foundation 10 through the platform; at the same time, the arrangement of the stiffeners also helps to balance the stress distribution in the connection area between the coal mill base 50 and the platform, avoiding stress concentration.

[0041] In some embodiments, the anchoring foundation 10 includes: a pit 101 formed by excavation in the ground area;

[0042] A concrete substrate 102 is poured into the pit 101, and the top surface of the concrete substrate 102 is leveled to form a rigid load-bearing platform 103; and

[0043] Anchor bolt 104, the lower end of anchor bolt 104 is anchored inside the concrete substrate 102, and its upper end is fastened to the transition bearing member 20.

[0044] Based on the above specific embodiments, the anchoring foundation 10 is formed as follows:

[0045] First, in the ground area around the coal mill base 50, a pit 101 with a predetermined size is excavated according to the design requirements. More specifically, a continuous or segmented pit 101 with a depth of 100mm is excavated around the outer edge of the base within a range of 620mm.

[0046] Then, C40 grade concrete is poured into the pit 101 to form a concrete substrate 102. Before or during the pouring process, it is ensured that the top surface of the concrete substrate 102 can form a flat, rigid load-bearing platform 103 that can stably support the transition load-bearing member 20 after curing. This can be achieved through formwork control and surface treatment.

[0047] Anchor bolt 104, an M36×900mm grade 8.8 carbon steel bolt, has its lower end (the end with the hook or anchor plate) pre-embedded and anchored inside the concrete substrate 102 to ensure sufficient pull-out resistance. The upper end (threaded end) of anchor bolt 104 extends out of the top surface of the concrete substrate 102 for subsequent fastening connection with the transition bearing member 20 (platform). The pre-embedded depth of anchor bolt 104 is 800mm, and its hole (Φ150×800mm) will be filled with H-40 high-strength grout 105 after bolt installation to enhance the anchoring effect.

[0048] In some embodiments, the leveling pad 30 is one or more sets of metal pads with adjustable thickness, which are used to adjust the levelness of the transition bearing 20 and the uniformity of the bottom support.

[0049] Based on the above specific embodiments, when installing the transition bearing member 20 (steel platform) on the rigid bearing platform 103 of the concrete substrate 102, a leveling pad 30 is set between the bottom of the platform and the concrete bearing platform to accurately adjust its levelness and ensure the uniformity of the bottom support. This leveling pad 30 can specifically be one or more sets of metal shims with adjustable thickness. During installation, based on the reading of the level measuring instrument, the number of shims is increased or decreased below different support points of the platform, or shims of different thicknesses are replaced, until the platform reaches the preset level accuracy requirement. These metal shims typically have high compressive strength and can withstand the loads of the platform and the superstructure.

[0050] In some embodiments, the transition bearing member 20 is a steel structure platform with reinforcing ribs, which are used to improve the overall bending and torsional stiffness of the steel structure platform; the steel structure platform is provided with through holes corresponding to the anchor bolts 104, and the anchor bolts 104 pass through the through holes and are fastened to the steel structure platform.

[0051] Based on the above specific implementation method, the transition bearing member 20 can be one or more custom-made steel structure platforms made of steel plates with a thickness of 30mm. To improve the overall bending and torsional stiffness of the steel structure platform (platform), it can be designed with a specific shape or have reinforcing ribs welded to its bottom or sides. The steel structure platform has multiple through holes, the positions of which correspond to the positions of the anchor bolts 104 pre-embedded in the anchor foundation 10. During installation, the anchor bolts 104 pass through these through holes, and then the steel structure platform (platform) is fastened to the anchor foundation 10 using nuts.

[0052] In some embodiments, the connecting reinforcement 40 is a triangular reinforcement plate, and the two sides of the triangular reinforcement plate are rigidly connected to the top surface of the transition bearing member 20 and the side wall of the coal mill base 50, respectively.

[0053] Based on the above specific embodiments, the connecting reinforcement 40 is specifically a triangular reinforcing plate. These triangular reinforcing plates are also made of steel or welding materials compatible with the platform and base. They are equilateral triangles with an obtuse angle of 120° and two sides of 500mm in length. During installation, one side of the triangular reinforcing plate is firmly connected to the top surface of the transition bearing 20 (steel structure platform / platform) by welding, while the other side is firmly connected to the side wall of the coal mill base 50 by welding. In this way, multiple stable triangular support structures are formed between the platform and the coal mill base 50, achieving a rigid connection.

[0054] In some embodiments, the concrete matrix 102 is further provided with a steel cage consisting of multiple layers of bidirectional threaded steel bars.

[0055] Based on the above specific embodiments, in order to further enhance the tensile strength and overall bearing capacity of the concrete matrix 102 in the anchorage foundation 10 and prevent cracking, a reinforcing cage can be installed inside it. This reinforcing cage is typically composed of multiple layers (two or more layers) of bidirectionally arranged threaded steel bars. The steel bars are arranged in a mesh at certain intervals and fixed with wire or welding. The reinforcing cage is placed in the predetermined position in the pit 101 before pouring concrete, ensuring sufficient concrete cover.

[0056] In some embodiments, the lower end anchoring hole of the anchor bolt 104 is filled with grout 105.

[0057] Based on the above specific embodiments, when the anchor bolt 104 (M36×900mm) is installed in the pre-drilled hole (Φ150×800mm) in the concrete substrate 102, in order to ensure a tight bond between the anchor bolt 104 and the concrete substrate 102, provide strong anchoring force and transfer load, after the anchor bolt 104 is positioned, high-strength non-shrink grout 105 will be filled into the anchoring hole at its lower end. H-40 high-strength grout 105 has good fluidity (≥280mm) and early high strength characteristics, which can fully fill the gap of the hole and form a firm bond with the bolt and the hole wall.

[0058] In some embodiments, the outer shell 501 of the coal mill base 50 is rigidly connected with a square reinforcing plate 60.

[0059] Based on the above specific embodiments, in order to further improve the overall rigidity of the upper structure of the coal mill and reduce the relative vibration between the coal mill base 50 and the casing, square reinforcing plates 60 can be rigidly connected around the outer casing 501 of the coal mill base 50 by welding or other methods. For example, square steel plates with dimensions of 1600mm × 120mm × 40mm can be used and welded to the joint between the coal mill base 50 and the casing, or directly welded to the outer surface of the casing, either around the perimeter or arranged in key locations. These square reinforcing plates 60 act like reinforcing rings or reinforcing ribs, constraining the deformation of the casing and improving its resistance to vibration.

[0060] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A vibration damping structure for a coal mill base, characterized by, The vibration damping structure includes: An anchoring foundation is provided in the ground area around the outer periphery of the coal mill base; the anchoring foundation provides a rigid bearing platform and is used to receive and disperse vibration energy from the coal mill base. At least one transition bearing member is provided, which is fastened to the anchoring foundation; a leveling pad is also provided between the rigid bearing platform and the transition bearing member; And at least one set of connecting reinforcement members, the two ends of which are rigidly connected to the transition bearing member and the coal mill base, respectively. The connecting reinforcement members are used to effectively transfer the vibration energy originating from the coal mill base to the transition bearing member and to balance the stress distribution in the connection area between the coal mill base and the transition bearing member.

2. The damping structure for a coal mill base according to claim 1, wherein The anchoring foundation includes: a pit or trench excavated in the ground area; The concrete substrate poured into the pit, the top surface of which is leveled to form the rigid load-bearing platform; and Anchor bolts, the lower end of which is anchored inside the concrete matrix, and the upper end of which is fastened to the transition bearing member.

3. The damping structure for a coal mill base according to claim 2, wherein The leveling pad is one or more sets of metal pads with adjustable thickness, which are used to adjust the levelness of the transition bearing and the uniformity of the bottom support.

4. The damping structure for a coal mill base according to claim 2 or 3, characterized in that, The transition bearing member is a steel structure platform with reinforcing ribs, which are used to improve the overall bending and torsional stiffness of the steel structure platform; the steel structure platform is provided with through holes corresponding to the anchor bolts, and the anchor bolts pass through the through holes and are fastened to the steel structure platform.

5. The damping structure for a coal mill base according to claim 4, wherein The connecting reinforcement is a triangular reinforcing plate, and the two sides of the triangular reinforcing plate are rigidly connected to the top surface of the transition bearing member and the side wall of the coal mill base, respectively.

6. The damping structure for a coal mill base according to claim 5, wherein The concrete matrix is ​​also equipped with a steel cage consisting of multiple layers of bidirectional threaded steel bars.

7. The damping structure for a coal mill base according to claim 6, wherein The lower anchoring hole of the anchor bolt is filled with grout.

8. The damping structure for a coal mill base according to claim 7, wherein The outer shell of the coal mill base is rigidly connected with square reinforcing plates.

9. A coal mill apparatus characterised in that, Including the vibration reduction structure as described in any one of claims 1-8.

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