Clamping mechanism for half-finishing of bulkhead sleeve

Abstract

The utility model relates to a half -finishing clamping mechanism of baffle sleeve, including vertical lathe workstation, be provided with a plurality of radial clamping mechanism and a plurality of vertical support column on vertical lathe workstation, every radial clamping mechanism is provided with support block and clamping block, be provided with pressure sensor between support block and clamping block, support block, pressure sensor and clamping block follow the radial of vertical lathe workstation towards vertical lathe workstation center and set gradually, be provided with three -axis acceleration sensor on the clamping block. When the face of being processed exists casting defect, the moment of tool reaches the defect, cutting force can produce greater change, simultaneously, the obvious vibration anomaly of turning tool and baffle sleeve, through pressure sensor detection each clamping block to the clamping force of baffle sleeve, through three -axis acceleration sensor detection clamping block's vibration frequency and vibration amplitude, can judge whether the defect appears according to the detection result.

Description

Technical Field

[0001] This utility model belongs to the field of partition sleeve processing equipment, and in particular a partition sleeve semi-finishing clamping mechanism. Background Technology

[0002] The turbine diaphragm sleeve is made of ZG15CrMoA alloy castings and requires rough machining, semi-finishing, and finishing before it can be put into use. Some castings have minor casting defects. In traditional machining processes, a 5mm finishing allowance is left on each side after semi-finishing. This excessive material thickness masks casting defects (such as sand holes, porosity, and slag inclusions), preventing them from being fully exposed. These defects are only discovered during later finishing, requiring machine shutdown and repair welding, which not only affects delivery time and increases production costs but also damages the company's reputation and poses significant quality risks. To solve this problem, the finishing allowance can be reduced during semi-finishing, allowing potential casting defects to be exposed earlier and repaired in advance without affecting the finishing progress and quality. When repairing defects, the defect is usually removed first to form a pit, and then welded into the pit. During welding, welding deformation is prone to occur. If the finishing allowance is too small, the welding deformation may exceed the finishing allowance, resulting in the finished partition sleeve not meeting the size requirements. Therefore, it is best to check for casting defects on the machined surface during semi-finishing. If casting defects are found, more finishing allowance is reserved for some machined surfaces according to the location of the defects to ensure the dimensional accuracy after finishing. If no casting defects are found, smaller finishing allowance is reserved for all machined surfaces to reduce the amount of cutting during finishing, improve finishing efficiency, and ensure machining quality.

[0003] Traditional methods for detecting casting defects include various approaches, such as inducing eddy currents on the workpiece surface using an alternating magnetic field (casting defects disturb these eddy currents, causing changes in the impedance or voltage of the detection coil), acquiring workpiece surface images using high-resolution industrial cameras and multi-angle light sources, ultrasonic testing, and industrial CT scanning. However, monitoring for casting defects on the machined surface during semi-finishing requires integrating these detection devices into the machine tool, which is quite challenging. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a clamping mechanism for semi-finishing of partition sleeves, which can indirectly monitor whether casting defects occur on the machined surface during the semi-finishing process, thereby reducing the difficulty of monitoring.

[0005] To solve the above problems, the technical solution adopted by this utility model is as follows: a partition sleeve semi-finishing clamping mechanism, including a vertical lathe worktable, on which multiple radial clamping mechanisms and multiple vertical support columns are arranged.

[0006] Each of the radial clamping mechanisms is provided with a support block and a clamping block, and a pressure sensor is provided between the support block and the clamping block. The support block, pressure sensor and clamping block are arranged in sequence along the radial direction of the vertical lathe worktable toward the center of the vertical lathe worktable; a triaxial acceleration sensor is provided on the clamping block.

[0007] Furthermore, the support block is fixedly connected to the radial clamping mechanism, the pressure sensor is fixedly connected to the support block, and there is a gap between the clamping block and the radial clamping mechanism; the side wall of the clamping block is provided with a stud, the stud penetrates the support block and is clearance-fitted with the support block, and the end of the stud is provided with a locking nut.

[0008] Furthermore, the radial clamping mechanism includes a slide table, the upper surface of the vertical lathe worktable is provided with a radially extending dovetail groove, the bottom of the slide table is provided with a dovetail-shaped slider, the slider is located in the dovetail groove and slides in cooperation with the dovetail groove; the slide table is connected to a locking mechanism.

[0009] Furthermore, the locking mechanism consists of multiple locking screws; a slide block is provided on the slide table that slides with the slide table, the slide block is connected to a clamping drive mechanism, and the support block is fixedly connected to the slide block.

[0010] Furthermore, the clamping drive mechanism is a drive screw, which is rotatably mounted on the slide and threadedly engaged with the slide block.

[0011] Furthermore, there are four radial clamping mechanisms, which are evenly distributed radially.

[0012] The beneficial effects of this utility model are as follows: In this utility model, a vertical lathe is used to machine the partition sleeve. When there are no defects on the machined surface, the cutting tool can cut stably, and the cutting force and the vibration of the partition sleeve are stable. When there are casting defects on the machined surface, the cutting force will change significantly the instant the tool reaches the defect. For example, when the tool encounters a pore or sand hole, the cutting edge instantly loses material support, and the cutting force will drop sharply. When the tool cuts out of the defect and re-cuts into the healthy material, the cutting force will rise sharply again. The whole process is completed within milliseconds. When the tool encounters a crack or hard point, the cutting force first rises sharply and then drops sharply. In addition, defects will cause obvious abnormal vibrations in the cutting tool and the partition sleeve.

[0013] In this invention, pressure sensors detect the clamping force of each clamping block on the partition sleeve. In an ideal rigid system, the clamping force is constant. However, in reality, the workpiece, fixture, and cutting tool can be considered an elastic system. When the cutting force changes, this system will produce slight elastic deformation, altering the load distribution of each clamping block, i.e., the clamping force changes. The pressure sensor can detect this change. When the partition sleeve is clamped but not yet turned, the clamping forces of each clamping block are balanced, and the system is in static equilibrium. During cutting, the cutting force of the cutting tool acts on the workpiece. To resist the cutting force, the workpiece tends to have slight displacement or rotation. This tendency causes changes in the contact pressure and micro-gap between the workpiece and each clamping block. The pressure at some clamping points increases (sharing part of the cutting force), while the pressure at others decreases (even showing a tendency for momentary micro-separation). When the cut surface of the diaphragm sleeve is free of defects, the material is uniform and intact, and the cutting force remains stable. As the depth of cut and tool feed change, the clamping force exhibits stable, periodic, minute fluctuations, with the fluctuation frequency matching the dominant frequency of the cutting force. The signals at each clamping point change in a regular and coordinated manner. When the tool encounters a defect, if the cutting force decreases suddenly, the previously clamped diaphragm sleeve tends to spring back; if the cutting force increases suddenly, the diaphragm sleeve tends to further shift or rotate. Both of these will cause abrupt changes in the clamping force of each clamping block 18. Therefore, based on the detection results of each pressure sensor, it is possible to preliminarily determine whether the tool has encountered a defect.

[0014] Meanwhile, when the cutting tool encounters a defect, it will cause the partition sleeve to vibrate irregularly, breaking the original stable vibration amplitude and frequency. The vibration of the partition sleeve will be transmitted to the clamping block. Therefore, the vibration frequency and vibration amplitude of the clamping block are detected by a three-axis accelerometer. When the vibration frequency and vibration amplitude of the clamping block suddenly change significantly, it indicates that the cutting tool has encountered a welding defect.

[0015] If the pressure sensor detects a sudden change in pressure value along with sudden changes in the vibration frequency and amplitude of the clamping block, it can be assumed that the cutting tool has encountered a welding defect. If, during the turning process of a critical surface, neither the pressure sensor nor the triaxial accelerometer detects a sudden change, it is assumed that there is no defect on that critical surface. Attached Figure Description

[0016] Figure 1 This is a top view of the present invention;

[0017] Figure 2 yes Figure 1 Schematic diagram of the AA section;

[0018] Figure 3 yes Figure 2 A schematic diagram of the square structure in section C;

[0019] Figure 4 yes Figure 3Schematic diagram of the BB section;

[0020] Figure 5 This is a schematic diagram of clamping the partition sleeve;

[0021] Reference numerals: 1—Vertical lathe worktable; 2—Support block; 3—Clamping block; 4—Pressure sensor; 5—Triaxial accelerometer; 6—Stud; 7—Locking nut; 8—Support column; 9—Slide table; 10—Dovetail groove; 11—Slider; 12—Locking mechanism; 13—Slide seat; 14—Clamping drive mechanism. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] The semi-finished clamping mechanism for the partition sleeve of this utility model, such as Figures 1 to 5 As shown, the machine includes a vertical lathe worktable 1, which is a conventional structure for vertical lathes. The vertical lathe worktable 1 is equipped with multiple radial clamping mechanisms and multiple vertical support columns 8. There are at least three radial clamping mechanisms, preferably four, used to clamp and fix the outer circumferential surface of the partition sleeve. The support columns 8 are used to support the bottom surface of the partition sleeve. There are typically four or six support columns 8, which can be fixed to the vertical lathe worktable 1 with screws, and their positions are adjustable. The four radial clamping mechanisms and the support columns 8 are evenly distributed radially around the center of the vertical lathe worktable 1.

[0024] Each radial clamping mechanism is provided with a support block 2 and a clamping block 3. A pressure sensor 4 is provided between the support block 2 and the clamping block 3. The support block 2, the pressure sensor 4 and the clamping block 3 are arranged in sequence along the radial direction of the vertical lathe worktable 1 toward the center of the vertical lathe worktable 1. A triaxial acceleration sensor 5 is provided on the clamping block 3.

[0025] The clamping block 3 directly contacts the partition sleeve and is used to clamp the partition sleeve. The pressure sensor 4 is used to detect the pressure between the clamping block 3 and the support block 2, thereby obtaining the clamping force of the clamping block 3 on the partition sleeve. The triaxial accelerometer 5 can detect the vibration amplitude and vibration frequency of the clamping block 3. The existing triaxial accelerometer 5 can detect vibrations at the micrometer level, so the detection accuracy is high.

[0026] During clamping, place the partition sleeve horizontally on each support column 8, adjust the position of the partition sleeve, and when the partition sleeve is coaxial with the vertical lathe worktable 1, push each radial clamping mechanism to move towards the partition sleeve, so that the clamping block 3 clamps the outer circumference of the partition sleeve.

[0027] When the machined surface of the diaphragm sleeve is free of defects, the cutting tool can cut stably, and the cutting force and vibration of the diaphragm sleeve remain stable. When casting defects exist on the machined surface, the cutting force changes significantly the instant the tool reaches the defect. For example, when the tool encounters a pore or sand hole, the cutting edge instantly loses material support, and the cutting force drops sharply. When the tool cuts out of the defect and re-cuts into healthy material, the cutting force rises sharply again. The entire process is completed within milliseconds. When encountering cracks or hard spots, the cutting force first rises sharply and then drops sharply. At the same time, defects cause significant abnormal vibrations in both the cutting tool and the diaphragm sleeve.

[0028] In an ideal rigid system, the clamping force of clamping block 3 is constant. However, in reality, the workpiece, fixture, and cutting tool form an elastic system. When the cutting force changes, this system undergoes slight elastic deformation, altering the load distribution of each clamping block 3, i.e., the clamping force changes. Pressure sensor 4 can detect this change. When the partition sleeve is clamped but not yet turned, the clamping forces of each clamping block 3 are balanced, and the system is in static equilibrium. During cutting, the cutting force of the cutting tool acts on the partition sleeve. To resist the cutting force, the partition sleeve tends to have slight displacement or rotation. This tendency causes changes in the contact pressure and micro-gap between the partition sleeve and each clamping block 3. The pressure at some clamping points increases (sharing part of the cutting force), while the pressure at others decreases (even showing a tendency for momentary micro-separation). When the cut surface of the partition sleeve is free of defects, the material is uniform and intact, and the cutting force remains stable. As the depth of cut and the cutting tool feed change, the clamping force exhibits stable, periodic, slight fluctuations. The fluctuation frequency is consistent with the main frequency of the cutting force, and the signals at each clamping point change regularly and in sync. When the cutting tool encounters a defect, if the cutting force decreases suddenly, the originally clamped partition sleeve tends to spring back; if the cutting force increases suddenly, the partition sleeve tends to shift or rotate further. Both of these will cause a sudden change in the clamping force of each clamping block 3, and the pressure sensor 4 can detect the change in clamping force. Therefore, based on the detection results of each pressure sensor 4, it is possible to preliminarily determine whether the cutting tool has encountered a defect.

[0029] Meanwhile, when the cutting tool encounters a defect, it will cause the partition sleeve to vibrate irregularly, breaking the original stable vibration amplitude and frequency. The vibration of the partition sleeve will be transmitted to the clamping block 3. Therefore, the vibration frequency and vibration amplitude of the clamping block 3 are detected by the triaxial acceleration sensor 5. When the vibration frequency and vibration amplitude of the clamping block 3 suddenly change significantly, it indicates that the cutting tool has encountered a welding defect.

[0030] If pressure sensor 4 detects a sudden change in pressure value, and triaxial accelerometer 5 detects sudden changes in vibration frequency and amplitude, it can be assumed that the cutting tool has encountered a welding defect. If, during the turning process of a critical surface, neither pressure sensor 4 nor triaxial accelerometer 5 detects a sudden change in value, it is assumed that there is no defect on that critical surface.

[0031] Both the pressure sensor 4 and the triaxial accelerometer 5 are small components, easy to install, require no major modifications to the machine tool, and have low implementation costs.

[0032] In this invention, the support block 2 is fixedly connected to the radial clamping mechanism, and the pressure sensor 4 is fixedly connected to the support block 2. There is a gap between the clamping block 3 and the radial clamping mechanism, meaning the clamping block 3 does not directly contact the radial clamping mechanism. A stud 6 is provided on the side wall of the clamping block 3, passing through the support block 2 and fitting with it with a clearance. A locking nut 7 is provided at the end of the stud 6. This installation method ensures both stable installation of the clamping block 3 and the transmission of the clamping force between the clamping block 3 and the partition sleeve to the pressure sensor 4.

[0033] In this invention, the radial clamping mechanism includes a slide table 9. The upper surface of the vertical lathe worktable 1 is provided with a radially extending dovetail groove 10. A dovetail-shaped slider 11 is provided at the bottom of the slide table 9, and the slider 11 is located in and slidably engages with the dovetail groove 10. A locking mechanism 12 is connected to the slide table 9. A support block 2 and a clamping block 3 are mounted on the slide table 9. The slide table 9 can slide along the dovetail groove 10, thereby driving the clamping block 3 to move radially, so that the clamping block 3 reaches the clamping position.

[0034] The locking mechanism 12 can be a hydraulic cylinder. The hydraulic cylinder can both drive the slide 9 to move as a whole and provide a stable clamping force, so that the clamping block 3 clamps the outer circle of the partition sleeve. After the clamping block 3 is clamped, the slide 9 can remain stable as a whole without the need for additional positioning equipment. This driving method can simplify the structure of the radial clamping mechanism, make clamping convenient, and provide a large clamping force. However, the hydraulic cylinder requires a matching hydraulic system, which increases the cost.

[0035] To reduce costs, the locking mechanism 12 can also consist of multiple locking screws. A through hole is provided on the slide table 9, through which the locking screws pass and are threadedly connected to the locking block. The locking block slides in engagement with the vertical lathe worktable 1. After the slide table 9 moves to the appropriate position, tightening the locking screws can keep the slide table 9 fixed. A slide block 13 is provided on the slide table 9, which slides in engagement with the slide table 9. The slide block 13 is connected to a clamping drive mechanism 14, and the support block 2 is fixedly connected to the slide block 13. The clamping drive mechanism 14 can push the slide block 13 to move radially along the vertical lathe worktable 1. The slide block 13 drives the support block 2 and the clamping block 3 to move, causing the clamping block 3 to contact the outer circle of the partition sleeve and clamp the partition sleeve. The clamping drive mechanism 14 can be a drive screw, which is rotatably mounted on the slide table 9 and threadedly engaged with the slide block 13.

[0036] When clamping, first loosen the locking screw, push the slide 9 to the appropriate position, then rotate the drive screw, the drive screw pushes the slide 13 to move, and the slide 13 drives the clamping block 3 to clamp the partition sleeve.

[0037] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A semi-finishing clamping mechanism for partition sleeves, comprising a vertical lathe worktable (1), wherein the vertical lathe worktable (1) is provided with multiple radial clamping mechanisms and multiple vertical support columns (8), characterized in that: Each of the radial clamping mechanisms is provided with a support block (2) and a clamping block (3), and a pressure sensor (4) is provided between the support block (2) and the clamping block (3). The support block (2), the pressure sensor (4) and the clamping block (3) are arranged in sequence along the radial direction of the vertical lathe worktable (1) toward the center of the vertical lathe worktable (1). A triaxial acceleration sensor (5) is provided on the clamping block (3).

2. The semi-finishing clamping mechanism for the partition sleeve as described in claim 1, characterized in that: The support block (2) is fixedly connected to the radial clamping mechanism, the pressure sensor (4) is fixedly connected to the support block (2), and there is a gap between the clamping block (3) and the radial clamping mechanism; the side wall of the clamping block (3) is provided with a stud (6), the stud (6) passes through the support block (2) and is clearance-fitted with the support block (2), and the end of the stud (6) is provided with a locking nut (7).

3. The semi-finishing clamping mechanism for the partition sleeve as described in claim 1, characterized in that: The radial clamping mechanism includes a slide (9), the upper surface of the vertical car worktable (1) is provided with a radially extending dovetail groove (10), the bottom of the slide (9) is provided with a dovetail-shaped slider (11), the slider (11) is located in the dovetail groove (10) and slides in cooperation with the dovetail groove (10); the slide (9) is connected to a locking mechanism (12).

4. The semi-finishing clamping mechanism for the partition sleeve as described in claim 3, characterized in that: The locking mechanism (12) consists of multiple locking screws; the slide (9) is provided with a slide seat (13) that slides and engages with the slide (9), the slide seat (13) is connected to a clamping drive mechanism (14), and the support block (2) is fixedly connected to the slide seat (13).

5. The semi-finishing clamping mechanism for the partition sleeve as described in claim 4, characterized in that: The clamping drive mechanism (14) is a drive screw, which is rotatably mounted on the slide (9) and threadedly engaged with the slide (13).

6. The semi-finishing clamping mechanism for the partition sleeve as described in claim 1, characterized in that: There are four radial clamping mechanisms, which are evenly distributed radially.

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