Special tool for disassembling and assembling mandrel of vertical centrifugal machine

Abstract

The utility model relates to the technical field of centrifugal machine mandrels, in particular to a special tool for disassembling and assembling a vertical centrifugal machine mandrel, which comprises a main shaft, the main shaft is of an integrally formed three-step structure, and the shaft diameters of the three steps are sequentially reduced; wherein British system threads are arranged on the outer portion of the section with the largest shaft diameter, and metric system threads are arranged on the outer portion of the section with the smallest shaft diameter. The three-section stepped shaft diameter and a double-system thread system are arranged, so that the structural strength and the adaptability are ensured. Linear thrust of the hydraulic jack is precisely and directionally transmitted to the mandrel through the stepped shaft diameter, meanwhile, self-weight loads of rotating components such as a speed reducer, a rotating drum and a rotor are balanced through a thread system, and safe unloading of pre-tightening force of a mandrel thread pair is achieved. The problems that in the traditional dismounting and mounting process, centering is poor, and threads are prone to being damaged are effectively solved, and the overhauling efficiency of the centrifugal machine mandrel is remarkably improved.

Description

Technical Field

[0001] This utility model relates to the field of centrifuge mandrel technology, and in particular to a special tool for disassembling and assembling a vertical centrifuge mandrel. Background Technology

[0002] During the operation of a vertical centrifuge, the bearing at the bottom of the rotor rotates synchronously with the drum. This means that traditional mandrel disassembly methods (mainly relying on manual labor and common tools such as jacks, pullers, and sledgehammers) require overcoming the weight of the rotating parts (approximately 2 tons). This generates significant frictional resistance at the threaded connections, greatly increasing the difficulty of maintenance. If forceful disassembly is used, it can easily damage the internal threads at the top of the mandrel. Therefore, traditional mandrel disassembly methods have certain defects and shortcomings, and there is room for further improvement and refinement. Summary of the Invention

[0003] To address the aforementioned problems, the purpose of this utility model is to provide a special tool for disassembling and assembling the mandrel of a vertical centrifuge. By applying a reverse support force in the axial direction through a hydraulic system, the self-weight of the rotating parts is balanced, thereby eliminating the thread preload and achieving safe and efficient disassembly and assembly of the mandrel.

[0004] The technical solution adopted in this utility model is as follows:

[0005] The present invention proposes a special tool for disassembling and assembling the spindle of a vertical centrifuge, which includes a main shaft. The main shaft is a three-section stepped structure integrally formed, with the shaft diameter of the three sections decreasing sequentially. The section with the largest shaft diameter has an imperial thread on the outside, and the section with the smallest shaft diameter has a metric thread on the outside.

[0006] Furthermore, the main shaft is made entirely of high-quality threaded steel.

[0007] Furthermore, the type of the rebar is 35CrMoA.

[0008] Furthermore, the tensile strength of the rebar is ≥1080 MPa.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] This utility model features a simple structure and convenient operation. Its structure employs a three-stage stepped shaft diameter and a dual-thread design, which significantly improves operational convenience while ensuring the mandrel's fitting accuracy. Using this tool greatly reduces the manpower required for mandrel assembly and disassembly, significantly shortens the operation time, and effectively reduces the torque required for disassembly, thereby reducing the risk of thread engagement damage. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0012] In the attached diagram, the reference numerals are: 1-spindle; 2-imperial thread; 3-metric thread. Detailed Implementation

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] It should be noted that in the description of this utility model, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not mean that the device or component must have a specific orientation, or be constructed and operated in a specific orientation.

[0015] See appendix Figure 1 The present invention proposes a special tool for disassembling and assembling the spindle of a vertical centrifuge, including a main shaft 1; the main shaft 1 is an integrally formed three-section stepped structure, with the shaft diameter of the three sections decreasing sequentially. In this embodiment, the shaft diameters of the three stepped structures are 47.3mm, 26mm and 24mm respectively, and the corresponding lengths are 70mm, 180mm and 200mm respectively.

[0016] One section with a shaft diameter of 47.3mm has an imperial thread on the outside, which can accurately match the internal thread specification of the mandrel; the other section with a shaft diameter of 24mm has a metric thread on the outside, which adopts a universal standard and is convenient for tightening with conventional nuts and tools on site.

[0017] The main shaft 1 is integrally machined from a high-quality 35CrMoA threaded steel forging, with a tensile strength ≥1080MPa.

[0018] This specialized tool meets both thread fit requirements and is compatible with the inner diameter of hydraulic jacks, optimizing stress distribution and ensuring structural strength. Both ends employ a dual-thread system, balancing specialization with versatility.

[0019] The linear thrust generated by the hydraulic jack is transmitted to a special tool (which bears tensile stress), ultimately unloading the preload of the mandrel thread pair.

[0020] This application applies axial linear thrust through a hydraulic jack, and tensile stress is borne by a special tool, which can directly unload the preload of the threaded pair. In contrast, when a traditional puller is operated, the spindle is subjected to radial force and rotational torque, which is prone to uneven load and thread damage.

[0021] The mechanical transmission mechanism can eliminate the thread preload in the axial direction, greatly reduce the torque required when disassembling the mandrel, and reduce the risk of thread engagement damage.

[0022] In use, this invention involves first screwing the imperial threaded section onto the top of the mandrel, then fitting the hydraulic jack onto the special tool, and finally tightening the metric threaded section of the tool with an M24 nut. Pressurization via a manual pump transmits the linear displacement of the hydraulic jack to the mandrel through the special tool, thereby unloading the preload on the threaded joint between the mandrel and the centrifuge top cover. The mandrel is then disassembled by unscrewing it with a wrench. For installation, the mandrel threads are tightened in the reverse direction using a wrench.

[0023] Matters not covered in this utility model are common knowledge.

[0024] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Any changes and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A special tool for disassembling and assembling the mandrel of a vertical centrifuge, characterized in that: The tool includes a spindle, which is a three-section stepped structure integrally formed, with the shaft diameter of the three sections decreasing sequentially; the section with the largest shaft diameter has an imperial thread on the outside, and the section with the smallest shaft diameter has a metric thread on the outside.

2. The special tool for disassembling and assembling the mandrel of a vertical centrifuge according to claim 1, characterized in that: The main shaft is made entirely of high-quality threaded steel.

3. A special tool for disassembling and assembling the mandrel of a vertical centrifuge according to claim 2, characterized in that: The type of rebar is 35CrMoA.

4. A special tool for disassembling and assembling the mandrel of a vertical centrifuge according to claim 2 or 3, characterized in that: The tensile strength of the rebar is ≥1080 MPa.

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