Main beam of centrifugal machine

Abstract

The invention belongs to the technical field of centrifugal machines, and particularly relates to a centrifugal machine main beam which comprises a C-shaped plate, the C-shaped plate comprises a top wall, a side wall and a bottom wall which are sequentially connected, a supporting sealing plate is arranged in a notch between the top wall and the bottom wall, and a main beam cavity is formed between the C-shaped plate and the supporting sealing plate. The cavity of the main beam is divided into a plurality of closed cavities by a plurality of closed reinforcing ribs; a plurality of overflowing reinforcing ribs are arranged in the closed cavity, each overflowing reinforcing rib is provided with a bevel edge, an overflowing through hole is formed between the bevel edge and the C-shaped plate, and a resonance mass center damping hole is formed in the center of each overflowing reinforcing rib; the supporting sealing plate is provided with a tenon-and-mortise connector, and the sealing reinforcing rib and the overflowing reinforcing rib are provided with tenon-and-mortise connectors matched with the sealing reinforcing rib and the overflowing reinforcing rib.

Description

Technical Field

[0001] This invention relates to the field of centrifuge technology, and more particularly to a centrifuge main beam. Background Technology

[0002] The main structure of a horizontal decanter centrifuge can be divided into static and dynamic components. The core of the dynamic components is the rotor, whose operation requires a platform with controllable constraints and safety protection. The base assembly, as the main static component and foundation platform supporting the rotation, has a crucial impact on the bearing housing (the position constraint component of the rotating body) due to its overall structural rigidity. In particular, the perpendicularity of the mounting surface and the parallelism of the mounting surfaces at both ends directly affect the long-term stable operation and vibration control of the rotating body. The rigidity of the base structure mainly relies on the rational design of the main beam, especially during the high-speed operation of the horizontal decanter centrifuge, where effective suppression of vibration and system resonance is necessary.

[0003] Currently, the domestic market for horizontal decanter centrifuges is dominated by medium and small-sized models (diameter less than φ800). In the design of large horizontal decanter centrifuges, to improve the simplicity of the appearance, the main beam typically adopts a rectangular cross-section design, but this faces the following technical challenges: (1) Insufficient structural rigidity and vibration suppression problem: The main beam of large horizontal screw centrifuge has a large span and a wide load-bearing surface, which causes the resonant centroid to deviate from the boundary constraint area, affecting the structural rigidity and making it difficult to effectively suppress vibration and system resonance during high-speed operation. Large centrifuges (such as centrifuges with a diameter of φ800 or more) may also generate higher-order frequencies because second-order and third-order vibrations may be excited during high-speed operation; (2) Welding process restricts the integrity of the structure: Traditional main beams rely on a lot of welding, but too many welds will reduce the strength and stability of the structure. The design needs to be optimized to reduce the length of the welds while ensuring the overall rigidity and load-bearing capacity. (3) The layout of stiffeners and the efficiency of support; stiffeners need to be set inside the main beam to improve the load-bearing capacity, but the existing design is difficult to balance lightweight and rigidity enhancement, and more efficient stiffener arrangement methods need to be explored. (4) The contradiction between lightweighting and cost control: The large amount of material used in the main beam leads to an increase in weight and manufacturing costs. It is necessary to optimize the structure, reduce material consumption and reduce production costs while ensuring rigidity. Summary of the Invention

[0004] This invention provides a horizontal screw centrifuge with low power loss and precise transmission speed.

[0005] The present invention provides a centrifuge main beam comprising a C-shaped plate, the C-shaped plate comprising a top wall, a side wall, and a bottom wall connected in sequence, a support sealing plate provided between the top wall and the bottom wall, and a main beam cavity formed between the C-shaped plate and the support sealing plate, the two ends of the main beam cavity being sealed by connecting plates, the main beam cavity being divided into several sealed chambers by several closed reinforcing ribs; several flow-through reinforcing ribs are provided in the sealed chambers, the flow-through reinforcing ribs having beveled edges, and flow-through holes being formed between the beveled edges and the C-shaped plate, the center of the flow-through reinforcing rib having a resonance centroid damping hole; the support sealing plate is provided with a tenon and mortise interface, and the closed reinforcing ribs and the flow-through reinforcing ribs are all provided with tenon and mortise joints that cooperate with them.

[0006] The beneficial effects are as follows: This invention overcomes the three major technical bottlenecks of "insufficient rigidity, difficulty in suppressing vibration, and complex manufacturing process" in the main beam of large horizontal screw centrifuges through innovative chamber division, mortise and tenon connection, and vibration control design. (1) Structural rigidity is significantly improved This design is suitable for the main beam of large horizontal screw centrifuges with a diameter exceeding φ1000 or an aspect ratio greater than 3.0. The reason is that the key to the centrifuge base's load-bearing capacity lies in the structural strength of the inner frame. In this design, the support plates, connecting plates, and bearing housing mounting plates are welded together to form a grid beam structure. The use of mortise and tenon joints ensures reliable lateral support and small-span constraint between the reinforcing ribs and the support plates, thereby improving the overall load-bearing span capacity and the main vertical load-bearing capacity of the main beam. The increased load-bearing span capacity leads to an increased aspect ratio, and the increased vertical load-bearing capacity allows for the support of larger rotating rotors.

[0007] Furthermore, the main beam cavity is divided into multiple sealed chambers by closed reinforcing ribs, forming an internal support system similar to a honeycomb structure. This significantly enhances the overall bending and torsional resistance of the main beam, making it particularly suitable for the large span load-bearing requirements of large horizontal screw centrifuges. The combination of C-shaped plates and support sealing plates forms a closed box girder structure. Combined with the internal reinforcing rib layout, this significantly reduces the deformation of the main beam under vertical and lateral loads (simulation data shows a stress-deformation displacement reduction of ≥15%).

[0008] (2) High-efficiency vibration suppression and resonance control The overall design employs a composite beam structure of grid beams, T-beams, and I-beams, which improves vertical load-bearing capacity, lateral torsional resistance, and longitudinal bending resistance. This directly strengthens the main load-bearing areas while weakening non-load-bearing areas, effectively utilizing materials where they are most needed to achieve superior performance with the same amount of material. Furthermore, according to the natural frequency formula f = (k / M)¹ / ², lightweight and high rigidity contribute to increasing the natural frequency.

[0009] The beveled design of the flow reinforcement ribs and the C-shaped plate form flow holes, which not only optimizes the flow path of the counterweight material (such as concrete), but also disperses the vibration wave transmission path through the hole structure, reducing high-frequency vibration energy. The resonant centroid vibration damping hole is located at the center of the flow reinforcement ribs. By adjusting the centroid distribution of the vibration modes and combining the mortise and tenon structure constraint, it effectively suppresses the second and third order resonant frequencies (the measured natural frequency increase is up to 208%).

[0010] (3) Lightweight and material optimization: By precisely matching the mortise and tenon joints and the joints, the welding length and thermal deformation risk are reduced, while avoiding material redundancy in traditional all-welded structures. Compared with the traditional δ20~δ25mm thick plate scheme, this design uses a δ16mm C-shaped plate plus a δ30mm support plate to meet the same or better strength, reducing material consumption by ≥30%, achieving "weight reduction without reducing rigidity".

[0011] (4) Improved processability and assembly efficiency The mortise and tenon structure (interface + joint) enables pre-positioning assembly of the reinforcing ribs and support plates, simplifying the welding process and reducing manual adjustment time, making it particularly suitable for mass production of large components. The linkage design between the "T"-shaped support plate and the reinforcing ribs makes the load transfer path more direct, reducing the impact of welding residual stress on the accuracy of the main beam.

[0012] (5) Multifunctional integrated design The through-flow holes and resonance center vibration damping holes also function as counterweight injection channels, solving the problem of dynamic balance adjustment in large centrifuges. The combined design of the lifting lug installation space and the reinforcing plate ensures lifting safety while avoiding interference with the internal structure of the main beam.

[0013] In summary, this solution improves the inherent frequency and reduces material costs, providing core supporting technology for the installation of domestically produced large-scale centrifuges (such as those with a diameter of φ1000 and above).

[0014] Furthermore, the flow-through reinforcing rib is hexagonal, comprising a top edge, an upper inclined edge, a left side, a lower inclined edge, a bottom edge, and a right side. The thickness direction of the flow-through reinforcing rib is perpendicular to the C-shaped plate and the supporting sealing plate. The top, left, and bottom edges that contact the C-shaped plate are all welded to the C-shaped plate. Two tenon-and-mortise joints are formed on the thick edge of the flow-through reinforcing rib that contacts the supporting sealing plate. First, the hexagonal shape combined with three-sided diagonal welding enhances the local connection strength and disperses stress concentration. Second, the flow-through holes formed by the upper and lower inclined edges optimize the flow efficiency of internal fluids (such as concrete pouring) while reducing structural weight. Finally, the tenon-and-mortise joint design enables rapid and precise positioning of the reinforcing rib and the supporting sealing plate, reducing welding deformation and improving assembly efficiency.

[0015] Furthermore, the shape of the closed reinforcing rib matches the inner cavity of the main beam, and its thickness direction is perpendicular to the C-shaped plate and the supporting sealing plate. The thick edge of the rib in contact with the C-shaped plate is symmetrically welded to the three sides of the C-shaped plate. The mortise and tenon joint is formed by the protrusion on the thick edge of the closed reinforcing rib in contact with the supporting sealing plate. The perfectly matched design of the closed reinforcing rib ensures the airtightness of the sealed cavity, effectively separates the vibration transmission path, and suppresses resonance.

[0016] Furthermore, the tenon joints of the closed reinforcing ribs and the flow-through reinforcing ribs are inserted into the corresponding tenon joints on the support sealing plate and then welded and fixed. The tenon structure achieves pre-fixation of components before welding, ensuring assembly accuracy, reducing the risk of misalignment during welding, and forming a double connection (mechanical + metallurgical combination) after welding, which significantly improves the fatigue life and vibration resistance at the joint.

[0017] Furthermore, several support pads are welded to the top wall of the C-shaped plate, and each support pad forms a "T"-shaped structure with the corresponding closed reinforcing rib or flow-through reinforcing rib in the cavity of the main beam below. The "T"-shaped structure directly transfers the force of the support pad to the reinforcing rib, optimizes the load distribution, and reduces the local stress on the top wall of the C-shaped plate.

[0018] Furthermore, connecting plates are installed at both ends of the main beam cavity, and two base plates are welded to the outer side of the bottom wall of the C-shaped plate. Each base plate is located below the connecting plate on the same side and forms a "T"-shaped structure with it. This enhances the bending stiffness at both ends of the main beam, provides a stable installation foundation for the vibration isolator, and further suppresses vibration transmission.

[0019] Furthermore, a lifting lug installation space is formed between the connecting plate and its adjacent closed reinforcing rib or flow-through reinforcing rib. A reinforcing plate is welded to the sidewall of the C-shaped plate within this space, and both the reinforcing plate and the sidewall of the C-shaped plate have through-holes for installation. A lifting lug with an ear hole is inserted into the installation hole, located outside the main beam cavity. The reinforcing plate enhances the local rigidity of the lifting lug installation area, preventing deformation of the main beam during hoisting. The external ear hole design facilitates hoisting operations while avoiding interference between the lifting lug and the internal structure of the main beam, ensuring both functionality and safety. Attached Figure Description

[0020] Figure 1 This is a front view of the main beam of a centrifuge. Figure 2 for Figure 1 A three-dimensional structural diagram (with support plates removed); Figure 3 for Figure 1 A cross-sectional view of the structure along line AA (the lug section); Attached reference numerals: 1. C-shaped plate, 2. Support sealing plate, 2-1. Tenon and mortise interface, 3. Connecting plate, 4. Support pad, 5. Base plate, 6. Enclosed reinforcing rib, 7. Overflow reinforcing rib, 8. Tenon and mortise joint, 9. Bypass overflow channel, 10. Resonance centroid vibration damping hole, 11. Reinforcing plate, 12. Lifting lug, 13. Ear hole. Detailed Implementation

[0021] This embodiment, in conjunction with the accompanying drawings, provides a detailed description of the connection relationships and functions of each part.

[0022] like Figures 1-3 As shown, a main beam of a horizontal screw centrifuge includes a C-shaped plate 1, which is integrally bent from a high-quality steel plate and includes a top wall, a side wall, and a bottom wall connected in sequence. The connection between the bottom wall and the side wall, and between the side wall and the top wall, are all rounded right angles. A support sealing plate 2 is welded at the gap between the top wall and the bottom wall, so that a main beam cavity is formed between the C-shaped plate 1 and the support sealing plate 2. The main beam cavity extends along the axial direction of the main beam.

[0023] Connecting plates 3 are installed at both ends of the main beam cavity. These connecting plates 3 are used to seal both ends of the main beam cavity. During the installation of the main beam, the connecting plates 3 are used for welding or connecting the bearing seat support components of the assembly base, and for installing the bearing seats in pairs. The vibration of the rotating body will be transmitted vertically to the main beam of the base and then to the vibration isolator, achieving shortest path vibration isolation or damping to protect the foundation and stabilize the product's operating state.

[0024] Several support pads 4 are welded to the top wall of the C-shaped plate 1. Each support pad 4 has a corresponding reinforcing rib (overflow reinforcing rib 7 or closing reinforcing rib 6) below it. The support pads 4 (closely attached to the top wall of the C-shaped plate 1) and the reinforcing ribs below them form a "T"-shaped structure. When the main beam is in use, the protective shell component of the rotating body is installed on the support pads 4, so that the force on the support pads 4 is transferred to the reinforcing ribs.

[0025] Two base plates 5 are welded to the outer side of the bottom wall of the C-shaped plate 1. These two base plates 5 are located below the left and right ends of the main beam cavity (i.e., the left and right end connecting plates 3). Each base plate 5 is located below the connecting plate 3 on the same side and forms a "T"-shaped structure with it. The base plate 5 is used to support the main beam and install vibration isolators.

[0026] In this embodiment, the main beam cavity is divided into several spatial chambers by several reinforcing ribs. These reinforcing ribs are of two types: flow-through reinforcing ribs 7 and closed reinforcing ribs 6. Tenon-and-mortise joints 2-1 are provided on the supporting sealing plate 2 at positions corresponding to each reinforcing rib. The specific connection method is as follows: (1) The closed reinforcing rib 6 is used to divide the main beam cavity into several closed chambers. Its shape is completely matched with the shape of the main beam cavity. Its plate thickness direction is perpendicular to the C-shaped plate 1 and the support sealing plate 2. The plate thickness edge that contacts the C-shaped plate 1 is symmetrically welded to the C-shaped plate 1 on three sides. The plate thickness edge that contacts the support sealing plate 2 protrudes to form two tenon joints 8. (2) The flow-through reinforcing rib 7 is installed in the sealed cavity. It is hexagonal in shape, including the top edge, left side, bottom edge, right side, upper inclined edge, and lower inclined edge. Its thickness direction is perpendicular to the C-shaped plate 1 and the supporting sealing plate 2. The thickness edge of the flow-through reinforcing rib 7 that contacts the C-shaped plate 1 is welded to the C-shaped plate 1 on three sides symmetrically. That is, the top edge, left side, and bottom edge of the flow-through reinforcing rib 7 are all welded to the C-shaped plate 1. In this way, flow-through holes (which also serve as bypass flow-through channels 9) are formed between the upper inclined edge and the C-shaped plate 1 and between the lower inclined edge and the C-shaped plate 1. A resonance centroid vibration damping hole 10 (which also serves as a central flow-through channel) is opened at the center of the flow-through reinforcing rib 7. The thickness edge of the flow-through reinforcing rib 7 that contacts the supporting sealing plate 2 protrudes to form two tenon joints 8.

[0027] (3) The tenon joints 8 of the closed reinforcing rib 6 and the flow reinforcing rib 7 are inserted into the corresponding tenon interface 2-1 on the support sealing plate 2 and then welded.

[0028] like Figure 2 As shown, in this embodiment, the lifting lug 12 is installed on the exposed outer side of the main beam. The specific connection method is as follows: the closed reinforcing rib 6 at the left and right ends of the main beam and the adjacent connecting plate 3 on the same side form the installation space of the lifting lug 12. In the installation space of the lifting lug 12, a reinforcing plate 11 is welded to the side wall of the C-shaped plate 1 (the surface of the reinforcing plate 11 is in close contact with the side wall of the C-shaped plate 1). Vertical installation openings are opened on the side wall of the reinforcing plate 11 and the C-shaped plate 1. The lifting lug 12 is an arc-shaped mechanism with one side smaller and the other side larger. The ear hole 13 of the lifting lug 12 is located at the small side end. Its small side end is inserted outward from the installation opening so that the ear hole 13 is located outside the cavity of the main beam, and then welded to the side wall of the reinforcing plate 11 and the C-shaped plate 1.

[0029] In this embodiment, the main beam needs to be concrete-poured according to the configuration required for centrifuge installation. The specific pouring method is as follows: the location of the closed reinforcing rib 6 is calculated based on the required counterweight weight and the torque of the machine base. The closed reinforcing rib 6 is then installed and welded to form a sealed chamber in the cavity of the main beam. The required counterweight weight is determined by the overall structure and operating conditions of the centrifuge product. The main influencing factors of the structure are the weight distribution of the rotating body parts and the position of the center of gravity. The main influencing factors of the operating conditions are the material type or density, material throughput (load), moisture content, etc.

[0030] Calculation Example: This embodiment of the invention features a single main beam structure, but in actual use, they need to be used in pairs. The rotors mounted on the main beam exhibit a non-uniform structure with large and small ends, and the offset distance L of the center of gravity causes a center of gravity offset moment M. 转 *L.

[0031] When the rotor is running, a certain concentration shift of the material inside causes a center of gravity offset moment, i.e., M. 物* ΔL1.

[0032] The main beam bears a uniform load, and the load is evenly distributed across the center of gravity at four points with vibration isolation installations at both ends. Therefore, according to the equilibrium state of the center of gravity eccentricity, counterweight calculations and pouring and sealing are required at the left end of the space of the main beam (concrete pouring area). Concrete is poured into the space cavity formed by the closed reinforcing rib 6 (the filling port is set on the bottom wall of the C-shaped plate 1). The concrete flows along the flow holes and the resonance center vibration damping holes 10 to the next flow reinforcing rib 7 until it reaches and fills the closed reinforcing rib 6, achieving the purpose of counterweighting the main beam and ultimately reducing the center of gravity eccentricity M of the main beam. 梁* ΔL2+M 物* ΔL1=M 转 *L.

[0033] Comparative experiment Numerical simulation was used to measure the natural frequencies of the main beam of a traditional structure with a span of 800 mm and the main beam of this embodiment. The detailed process is as follows: (1) The experimental subjects are shown in the table below:

[0034] (2) The experimental data are shown in the table below:

[0035] (3) Experimental conclusions: 1. Material saving: Theoretically, a 1000 specification product requires steel plates of equal thickness on four sides of δ23~δ25, but after optimization, only three sides of δ16 and one side of δ30 are required, saving ≥30% of materials.

[0036] 2. Improved structural stiffness: The mortise and tenon welding of the reinforcing ribs increases the natural frequency from 375Hz to 1157Hz (+208%), significantly improving vibration resistance. The thickened support plate 2, combined with mortise and tenon welding, increases the natural frequency by approximately 21%.

[0037] 3. Overall performance optimization: The natural frequency of the main beam (in the installed state) increased by 26% and in the non-installed state by 13%. Stress deformation decreased (≥8% in the non-installed state and about 15% in the installed state), indicating that the structure is more stable.

[0038] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A centrifuge main beam, comprising a C-shaped plate, the C-shaped plate comprising a top wall, a side wall, and a bottom wall connected in sequence, wherein a support sealing plate is provided at a notch between the top wall and the bottom wall, and a main beam cavity is formed between the C-shaped plate and the support sealing plate, characterized in that: The two ends of the main beam cavity are sealed by connecting plates. The main beam cavity is divided into several sealed chambers by several closed reinforcing ribs. Several flow-through reinforcing ribs are provided in the sealed chambers. The flow-through reinforcing ribs have beveled edges, and a flow-through hole is formed between the beveled edges and the C-shaped plate. A resonance centroid damping hole is opened in the center of the flow-through reinforcing rib. The support sealing plate is provided with mortise and tenon joints. The closed reinforcing ribs and the flow-through reinforcing ribs are all equipped with mortise and tenon joints that match them.

2. A centrifuge main beam according to claim 1, characterized in that: The C-shaped plate is integrally formed.

3. A centrifuge main beam according to claim 1 or 2, characterized in that: The flow-through reinforcing rib is hexagonal, comprising a top edge, an upper inclined edge, a left side, a lower inclined edge, a bottom edge, and a right side. The thickness direction of the flow-through reinforcing rib is perpendicular to the C-shaped plate and the supporting sealing plate. The top edge, left side, and bottom edge of the rib that contact the C-shaped plate are all welded to the C-shaped plate. Two tenon joints are formed by protrusions on the thick edge of the flow-through reinforcing rib that contacts the supporting sealing plate.

4. A centrifuge main beam according to claim 3, characterized in that: The shape of the closed reinforcing rib matches the inner cavity of the main beam, and its thickness direction is perpendicular to the C-shaped plate and the supporting sealing plate. The thickness edge of the plate in contact with the C-shaped plate is symmetrically welded to the three sides of the C-shaped plate. The mortise and tenon joint is formed by the protrusion on the thickness edge of the closed reinforcing rib in contact with the supporting sealing plate.

5. A centrifuge main beam according to claim 4, characterized in that: The tenon joints of the closed reinforcing ribs and the flow reinforcing ribs are inserted into the corresponding tenon joints on the support sealing plate and then welded and fixed.

6. A centrifuge main beam according to claim 5, characterized in that: Several support pads are welded to the top wall of the C-shaped plate. Each support pad forms a "T"-shaped structure with the corresponding closed reinforcing rib or flow reinforcing rib in the cavity of the main beam below it.

7. A centrifuge main beam according to claim 6, characterized in that: Connecting plates are installed at both ends of the main beam cavity. Two bottom plates are welded to the outer side of the bottom wall of the C-shaped plate. Each bottom plate is located below the connecting plate on the same side and forms a "T"-shaped structure with it.

8. A centrifuge main beam according to claim 7, characterized in that: The connecting plate forms a lifting lug installation space with its adjacent closed reinforcing rib or flow reinforcing rib. A reinforcing plate is welded to the side wall of the C-shaped plate in this space. The reinforcing plate and the side wall of the C-shaped plate have through installation openings. A lifting lug is inserted into the installation opening. The lifting lug has an ear hole located outside the cavity of the main beam.

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