Static pressure support pressing mechanism for steam turbine rotor machining

Abstract

The utility model discloses a static pressure support compression mechanism for steam turbine rotor processing belongs to steam turbine rotor processing technical field, including static pressure center stand, support mechanism and clamping mechanism, is set up positioning groove and rectangle groove on static pressure center stand, support mechanism is fixed in static pressure center stand lower part, and it is equipped with oil cavity in static pressure tile, and clamping mechanism detachably installs on static pressure center stand upper portion, including fixed crossbeam, inverted V type compression block, oil cylinder, locating block no.

Description

Technical Field

[0001] This utility model relates to the field of steam turbine rotor processing technology, and in particular to a hydrostatic support and clamping mechanism for steam turbine rotor processing. Background Technology

[0002] Steam turbine rotors are components of thermal and nuclear power plants, characterized by their large weight, high length-to-diameter ratio, and extremely high machining precision requirements. During precision machining processes such as turning or grinding, auxiliary support devices such as center supports must be used to ensure the rigidity of the rotor and prevent it from bending and deforming due to its own weight and cutting forces.

[0003] To meet these high-precision machining requirements, hydrostatic center supports have been widely used. By supporting the rotor on a high-pressure oil film, the hydrostatic center support achieves non-contact support, offering advantages such as high load-bearing capacity, high rigidity, high rotational accuracy, and near-zero wear, making it an ideal choice for machining heavy-duty rotors.

[0004] However, while providing bottom support, the hydrostatic center frame often requires an upper clamping mechanism to apply the necessary preload or balance the cutting force, ensuring the rotor is stably fixed. This presents a structural contradiction: on the one hand, the clamping mechanism must be firmly fixed to the center frame to provide stable clamping force; on the other hand, when loading and unloading heavy turbine rotors, this upper clamping mechanism must be moved aside or cleared to provide space for rotor hoisting.

[0005] In existing solutions, these clamping mechanisms or structures are bulky, making avoidance operations difficult and time-consuming; or they adopt movable designs, but during multiple avoidance and reset processes, it is difficult to ensure that the positioning reference is highly consistent. Such deviations in repeated positioning, or the slight movement of the center frame body during movement, will directly destroy the precise alignment state established by the hydrostatic support system, resulting in a decrease in processing accuracy, or even the need for realignment, which seriously affects processing efficiency and final product quality.

[0006] Therefore, this utility model proposes a hydrostatic support clamping mechanism for turbine rotor machining to overcome the shortcomings of the prior art. Utility Model Content

[0007] In view of the problems in the existing hydrostatic support clamping mechanism for turbine rotor machining, where the clamping mechanism causes the hydrostatic center frame to shift or repeatedly misposition when workpieces need to be avoided during loading and unloading, and the clamping force causes the rotor to bend and deform, this utility model aims to provide a hydrostatic support clamping mechanism for turbine rotor machining with an improved structure that can effectively solve the above problems.

[0008] This utility model provides a hydrostatic support clamping mechanism for turbine rotor machining, including: a hydrostatic center frame with a positioning groove and a rectangular groove; a support mechanism fixedly connected to the lower part of the hydrostatic center frame, the support mechanism including a hydrostatic bearing, the hydrostatic bearing being used to support the rotor, and the inner surface of the hydrostatic bearing having an oil cavity; and a clamping mechanism detachably installed on the upper part of the hydrostatic center frame and located directly above the hydrostatic bearing.

[0009] The clamping mechanism includes a fixed crossbeam, an inverted V-shaped pressure block, a hydraulic cylinder, a positioning block, a guide column, a fixing sleeve, a lifting eye bolt, and a transition sleeve positioning hole.

[0010] Furthermore, the two sides of the fixed crossbeam engage with the rectangular groove of the static pressure center frame; the inverted V-shaped pressure block is located below the fixed crossbeam; the hydraulic cylinder is vertically installed on the fixed crossbeam, and the piston rod of the hydraulic cylinder is connected to the inverted V-shaped pressure block; the positioning block is fixedly connected to both sides of the inverted V-shaped pressure block and cooperates with the positioning groove of the static pressure center frame; the lower end of the guide column is fixedly connected to the inverted V-shaped pressure block, and its upper end slides through the fixed crossbeam; the fixed sleeve is fixedly installed inside the fixed crossbeam and sleeved on the outer periphery of the guide column; the lifting eye bolt is threadedly connected to the upper surface of the fixed crossbeam; the transition sleeve positioning hole is opened on the fixed crossbeam.

[0011] Preferably, the contact point between the positioning block and the hydrostatic center frame is provided with a large gap and a small angle chamfer structure, so that the clamping mechanism can be gently guided during installation, avoiding installation collisions and improving the efficiency of repeated positioning.

[0012] Preferably, the oil cavity at the bottom of the static pressure bearing is connected to an external static pressure lubrication system through an internal oil passage. High-pressure oil provided by the external system enters the oil cavity through the internal oil passage, thereby forming a stable high-pressure oil film between the rotor and the static pressure bearing.

[0013] Preferably, the guide post is limited and guided by the fixed sleeve, and the guide post, the fixed sleeve and the cylinder fixing frame form a clamping mechanism. This guiding structure ensures the smoothness of the clamping action and the accuracy of the force direction.

[0014] Preferably, the fixed crossbeam is made of a material with damping properties, such as high-grade cast iron. The material properties, combined with the rectangular groove, allow the cylinder to drive the inverted V-shaped pressure block away from the rotor. The upward supporting force generated by the high-pressure oil film in the oil chamber of the static pressure pad is balanced by the pressure, clamping the rotor before indexing. The bending deformation generated in the clamping state protects the stable clamping of the workpiece and provides a good damping effect for the entire clamping mechanism, helping to suppress vibration during processing.

[0015] Preferably, the lifting eye bolt is used to cooperate with the lifting equipment to achieve the overall vertical lifting of the clamping mechanism after loosening, so as to provide sufficient clearance for the loading and unloading of the rotor, and the design solves the problem of clearance and displacement during the loading and unloading of the workpiece.

[0016] Preferably, the transition sleeve positioning hole is used to position and fix the casting core mold in the casting process of the fixed crossbeam. This is intended to ensure the stability of the casting structure and the accuracy of the internal channels.

[0017] This utility model has the following beneficial effects: 1. This utility model solves the problem that rigid clamping force in the prior art easily leads to the bending and deformation of the turbine rotor by setting the lower static pressure pad to provide static pressure oil film support. It achieves the goal of using the upward support force of the static pressure oil film to balance the downward clamping force, so that the rotor is subjected to force balance during processing, effectively avoiding workpiece bending and deformation, and significantly improving processing accuracy. 2. This utility model solves the problem in the prior art that the clamping mechanism is designed as an independent structure that can be vertically hoisted as a whole, and is hoisted using lifting eye bolts. This solves the problem that the clamping fixture is prone to displacement during the workpiece loading and unloading process, which can cause the static pressure center frame to move, or that the installation position is deviated due to frequent installation. This makes the workpiece loading and unloading convenient and quick, and the clamping mechanism can be accurately and repeatedly installed on the static pressure center frame, ensuring positioning accuracy. 3. This utility model solves the problems of difficult installation and inaccurate positioning of traditional large clamps by using the cooperation between the positioning block and the positioning groove, and the engagement between the fixed crossbeam and the rectangular groove for fixing during the installation of the clamping mechanism, and by setting a large gap and small angle chamfer for guidance, thus achieving smooth installation and precise and stable positioning. 4. This utility model, by setting a sliding fit between the guide post and the fixed sleeve, precisely guides the movement of the inverted V-shaped pressure block, solving the problem that the pressure block may deflect or shake under the drive of the hydraulic cylinder, ensuring that the clamping force is stably applied to the predetermined position. Combined with the shock absorption effect of the fixed crossbeam, it further improves the stability of the processing. Attached Figure Description

[0018] Figure 1 This is a front view of a hydrostatic support and clamping mechanism for machining a steam turbine rotor according to the present invention. Figure 2 for Figure 1 Enlarged view of point A in the middle; Figure 3 This is an exploded view of a hydrostatic support clamping mechanism for machining a steam turbine rotor according to this utility model; Figure 4 This is a schematic diagram of the clamping mechanism of the hydrostatic support clamping mechanism for turbine rotor machining proposed in this utility model; Figure 5 This is a schematic diagram of a hydrostatic support clamping mechanism for turbine rotor machining proposed in this utility model.

[0019] Legend: 1. Static pressure center frame; 2. Clamping mechanism; 201. Inverted V-shaped pressure block; 202. Positioning block one; 203. Guide column; 204. Fixing sleeve; 205. Transition sleeve positioning hole; 206. Lifting eye bolt; 3. Support mechanism; 301. Static pressure tile; 302. Positioning groove; 303. Rectangular groove; 304. Fixing crossbeam. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Example: Please refer to Figures 1 to 5 This utility model provides a hydrostatic support clamping mechanism for turbine rotor processing, which aims to solve the problems in the prior art where clamp avoidance during turbine rotor processing and unloading can easily lead to center frame movement or inaccurate positioning, and rigid clamping force can easily cause rotor bending and deformation.

[0022] like Figure 1 , Figure 3 , Figure 4 and Figure 5 As shown, a hydrostatic support and clamping mechanism for turbine rotor machining includes a hydrostatic center frame 1, a support mechanism 3, and a clamping mechanism 2. The hydrostatic center frame 1 serves as the mounting base for the entire mechanism. The hydrostatic center frame 1 has a positioning groove 302 and a rectangular groove 303 for installation. The support mechanism 3 is fixedly connected to the lower part of the hydrostatic center frame 1 and is used to support the rotor from below. The clamping mechanism 2 is detachably installed on the upper part of the hydrostatic center frame 1 and is located directly above the support mechanism 3. The clamping mechanism 2 is used to clamp the rotor from above.

[0023] Reference Figure 5 The support mechanism 3 includes a static pressure bearing 301. The inner surface of the static pressure bearing 301 is provided with an oil cavity for forming a static pressure oil film. The oil cavity at the bottom of the static pressure bearing 301 is connected to the external static pressure lubrication system through an internal oil passage. High-pressure oil is used to form a high-pressure oil film between the rotor and the static pressure bearing 301.

[0024] Reference Figure 3 and Figure 4The clamping mechanism 2 is an independent component that can be hoisted as a whole. The clamping mechanism 2 includes a fixed crossbeam 304, an inverted V-shaped pressure block 201, a hydraulic cylinder, a positioning block 202, a guide column 203, a fixed sleeve 204, a lifting eye bolt 206, and a transition sleeve positioning hole 205. The fixed crossbeam 304 is the main load-bearing component of the clamping mechanism 2. Both sides of the fixed crossbeam 304 engage with the rectangular groove 303 of the static pressure center frame 1. The transition sleeve positioning hole 205 is opened on the fixed crossbeam 304. The lifting eye bolt 206 is threaded onto the upper surface of the fixed crossbeam 304 for hoisting the clamping mechanism 2 as a whole. The hydraulic cylinder is vertically installed on the fixed crossbeam 304. The inverted V-shaped pressure block 202... 1 is located below the fixed crossbeam 304 and is used to press the rotor downward. The piston rod of the oil cylinder is connected to the inverted V-shaped pressure block 201 and is used to drive the inverted V-shaped pressure block 201 to move downward. The lower end of the guide column 203 is fixedly connected to the inverted V-shaped pressure block 201, and the upper end of the guide column 203 slides through the fixed crossbeam 304. The fixed sleeve 204 is fixedly installed inside the fixed crossbeam 304 and sleeved on the outer periphery of the guide column 203. The fixed sleeve 204 is used to guide the guide column 203. The positioning block 1 202 is fixedly connected to both sides of the inverted V-shaped pressure block 201. When the clamping mechanism 2 is installed, the positioning block 1 202 cooperates with the positioning groove 302 of the static pressure center frame 1.

[0025] Please refer to Figure 1 , Figure 2 and Figure 3 During the installation of the clamping mechanism 2 onto the static pressure center frame 1, the positioning block 202 on the clamping mechanism 2 cooperates with the positioning groove 302 on the static pressure center frame 1. At the same time, the fixed crossbeam 304 cooperates with the rectangular groove 303 on the static pressure center frame 1. The positioning block 202 has a large gap and small angle chamfer structure at the contact point with the static pressure center frame 1, so that the clamping mechanism 2 can be gently guided to the predetermined installation position when it is hoisted and lowered by the lifting eye bolt 206. This effectively avoids collisions and positional deviations during the installation process and ensures the positioning accuracy of multiple installations. The engagement of the two sides of the fixed crossbeam 304 with the rectangular groove 303 provides the clamping mechanism 2 with stable support and anti-torsion capability. The fixed crossbeam 304 is made of a material with shock-absorbing properties, which provides a shock-absorbing effect for the clamping mechanism 2.

[0026] The internal structure of the clamping mechanism 2 ensures its stability and accuracy. The lower end of the guide post 203 is fixedly connected to the inverted V-shaped pressure block 201, and its upper end slides through the fixed crossbeam 304. The fixed sleeve 204 is fixedly installed inside the fixed crossbeam 304 and sleeved on the outer periphery of the guide post 203. This sliding fit structure between the guide post 203 and the fixed sleeve 204 accurately guides and limits the movement trajectory of the inverted V-shaped pressure block 201, ensuring that the inverted V-shaped pressure block 201 can only reciprocate stably in the vertical direction under the drive of the hydraulic cylinder, without shaking or deflection, thereby accurately applying the clamping force to the rotor.

[0027] In order to achieve stable hydrostatic support, the oil cavity at the bottom of the hydrostatic bearing 301 is connected to the external hydrostatic lubrication system through an internal oil circuit. The external hydrostatic lubrication system provides the oil cavity with a continuous and stable high-pressure oil, thereby forming a high-rigidity non-contact high-pressure oil film between the rotor and the hydrostatic bearing 301.

[0028] As a specific implementation, in order to enhance the stability and vibration resistance of the device, the fixed crossbeam 304 is preferably made of a material with damping properties, such as high-grade cast iron or cast steel. Its material properties, together with the stable engagement with the rectangular grooves 303 on both sides, provide excellent damping effect for the clamping mechanism 2.

[0029] In addition, in order to ensure the structural strength and manufacturing precision of the fixed crossbeam 304, the transition sleeve positioning hole 205 is provided on it. In the casting process of the fixed crossbeam 304, it is used to accurately position and fix the casting core mold. This ensures the stability and dimensional accuracy of the internal structure of the casting, thereby ensuring the installation accuracy of the subsequent oil cylinder, guide column 203 and fixed sleeve 204.

[0030] Furthermore, the lifting eye bolts 206 threaded on the upper surface of the fixed crossbeam 304 are not only the lifting points for the installation and disassembly of the clamping mechanism 2, but also enable the entire clamping mechanism 2 as an independent module to be vertically lifted off the hydrostatic center frame 1, providing ample clearance for the loading and unloading of the rotor.

[0031] Working principle: Before processing, the turbine rotor is first placed on the hydrostatic bearing 301 of the support mechanism 3. Then, the oil cylinder vertically installed on the fixed crossbeam 304 is activated. The transition sleeve positioning hole 205 on the fixed crossbeam 304 is used to connect external components. The guide column 203 and the fixed sleeve 204 are installed on the oil cylinder fixing frame to form a clamping mechanism. Through the hydrostatic lubrication system, the oil pipe of the hydrostatic bearing 301 is connected to the hydrostatic system. Through the oil pipe, high-pressure oil enters the oil cavity at the bottom of the hydrostatic bearing 301 from the internal oil passage. A stable high-pressure oil film is formed between the contact surface of the hydrostatic center frame 1 and the hydrostatic bearing 301, so that the hydrostatic bearing 301 supplies oil to support the turbine rotor, and smoothly lifts the heavy rotor, realizing high-precision non-contact hydrostatic support.

[0032] After installation, the hydraulic cylinder returns to its original position, driving the inverted V-shaped pressure block 201 to move upward. Then, the rotor is indexed. After the indexing is complete, the static pressure plate 301 begins to release pressure, and the inverted V-shaped pressure block 201 presses down steadily. Then, the rotor is machined with fir-shaped grooves to prevent it from moving around.

[0033] Then, by reversing the hydraulic cylinder, the inverted V-shaped pressure block 201 is driven to detach from the rotor, increasing static pressure to make the rotor float. The rotor then rotates again to process the second batch of fir tree-shaped grooves. After each groove is processed, the rotor needs to be precisely rotated to process the fir tree-shaped grooves. This process is repeated for each rotor. After processing, the nut on the lifting eye bolt 206 is loosened, and the lifting eye bolt 206 lifts the entire clamping mechanism 2 and slowly raises it. During the raising process, the large-gap, small-angle chamfer structure on the positioning block 202 guides the positioning groove 302, making... The clamping mechanism 2 can move smoothly and accurately, and finally the positioning block 202 disengages from the positioning groove 302. At the same time, both sides of the fixed crossbeam 304 also disengage from the rectangular groove 303, completing the quick, accurate and repeatable installation of the clamping mechanism 2. Finally, the clamping mechanism 2 is loosened and vertically lifted off by the lifting eye bolt 206, providing clearance for the removal of the rotor. This separable and vertically hoisting design, combined with the precise positioning and matching structure, fundamentally solves the technical problem that traditional clamps are prone to center frame movement or installation position deviation when avoiding displacement.

Claims

1. A hydrostatic support clamping mechanism for machining a steam turbine rotor, comprising: A static pressure center frame (1) is provided with a positioning groove (302) for installation. And rectangular groove (303); Support mechanism (3), the support mechanism (3) is fixedly connected to the lower part of the hydrostatic center frame (1), the support mechanism (3) includes a hydrostatic bearing (301), the hydrostatic bearing (301) is used to support the rotor, and the inner surface of the hydrostatic bearing (301) is provided with an oil cavity for forming a hydrostatic oil film; The mechanism is characterized in that it further includes: Clamping mechanism (2), which is detachably mounted on the upper part of the static pressure center frame (1) and located directly above the static pressure tile (301); The clamping mechanism (2) includes: A fixed crossbeam (304) is provided, the two sides of which engage with the rectangular groove (303) of the static pressure center frame (1); An inverted V-shaped pressure block (201) is located below the fixed crossbeam (304) and is used to press the rotor downwards; The hydraulic cylinder is vertically mounted on the fixed crossbeam (304), and the piston rod of the hydraulic cylinder is connected to the inverted V-shaped pressure block (201) to drive the inverted V-shaped pressure block (201) to move downward. Positioning block 1 (202) is fixedly connected to both sides of the inverted V-shaped pressure block (201), and the positioning block 1 (202) cooperates with the positioning groove (302) of the static pressure center frame (1); The guide post (203) is fixedly connected at its lower end to the inverted V-shaped pressure block (201), and at its upper end slides through the fixed crossbeam (304). A fixing sleeve (204) is fixedly installed inside the fixing beam (304) and sleeved on the outer periphery of the guide post (203) for guiding the guide post (203); Eye bolt (206), the eye bolt (206) is threaded to the upper surface of the fixed crossbeam (304) and is used for the overall hoisting of the clamping mechanism (2); And a transition sleeve positioning hole (205), which is provided on the fixed crossbeam (304).

2. The hydrostatic support and clamping mechanism for turbine rotor machining according to claim 1, characterized in that, The contact point between the positioning block (202) and the static pressure center frame (1) is provided with a large gap and small angle chamfer structure, which is used to provide gentle guidance when the clamping mechanism (2) is installed.

3. The hydrostatic support and clamping mechanism for turbine rotor machining according to claim 1, characterized in that, The oil cavity at the bottom of the static pressure bearing (301) is connected to the external static pressure lubrication system through an internal oil passage. High-pressure oil is used to form a high-pressure oil film between the rotor and the static pressure bearing (301).

4. The hydrostatic support and clamping mechanism for turbine rotor machining according to claim 1, characterized in that, The guide post (203) is limited and guided by the fixed sleeve (204), and the guide post (203), the fixed sleeve (204) and the cylinder fixing frame form a pressing mechanism.

5. The hydrostatic support and clamping mechanism for turbine rotor machining according to claim 1, characterized in that, The cylinder drives the inverted V-shaped pressure block (201) to leave the rotor, and balances it with the upward supporting force generated by the high-pressure oil film in the oil chamber of the static pressure tile (301), and then indexes the rotor.

6. The hydrostatic support and clamping mechanism for turbine rotor machining according to claim 1, characterized in that, The fixed crossbeam (304) is made of a material with shock-absorbing properties and provides shock absorption for the clamping mechanism (2) by engaging with the rectangular groove (303).

7. The hydrostatic support and clamping mechanism for turbine rotor machining according to claim 1, characterized in that, The lifting eye bolt (206) is used to, after being loosened, cooperate with the lifting equipment to achieve the overall vertical lifting of the clamping mechanism (2) in order to solve the problem of avoiding displacement during the loading and unloading of workpieces.

8. The hydrostatic support and clamping mechanism for turbine rotor machining according to claim 1, characterized in that, The transition sleeve positioning hole (205) is used to fix the casting core mold during the casting process of the fixed crossbeam (304) to ensure the stability of the casting structure.

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