Tooling for power turbine blade tip shrouding and turning and method of use thereof

Abstract

The present application relates to a tool for power turbine blade tip rubbing and turning and its using method, in order to solve the problem of loose fixation at the root, size deviation of the tip arc and low yield rate of the product when the power turbine guide vane of the power turbine part of a certain gas turbine unit is rubbed in the process of the process impeller, the outer ring of the process impeller is provided with a plurality of special-shaped support tables which are inclined from one side to the other side, the gap between the adjacent two special-shaped support tables forms a blade tenon groove, the blade tenon groove is used for installing the blade, the connecting assembly for radial expansion of the tenon groove is arranged at the bottom of the blade tenon groove and is used for pressing the blade, the crown fixing block is used for positioning the crown of the two adjacent blades, one side of the plurality of special-shaped support tables is connected with the connecting pressure ring, the other side of each special-shaped support table is connected with the pressing plate, the pressing plate is provided with a square head cylindrical end fixing screw which is used for pressing the blade, and the present application is suitable for the intermittent cutting of the tip of the blade with similar structure and can improve the production efficiency.

Description

Technical Field

[0001] This invention relates to the field of tip polishing of power turbine blades, and more specifically to tooling for tip polishing and turning of power turbine blades and its usage method. Background Technology

[0002] The turbine guide vanes of a certain gas turbine unit have a longitudinal tree-shaped blade root and no crown structure. During the process assembly, the tips of the entire blade ring need to be machined on the process impeller to ensure the flow clearance of the unit and for subsequent frequency measurement, sequencing, and assembly. Due to the gap between the impeller tenon and the blade root, the previous process used bolts to tighten the bottom of the blade root and cast rosin to fix the blade steam passage. This process involved many steps and a long cycle, which affected the product processing efficiency to some extent. Moreover, due to the intermittent cutting during blade tip machining, the blade was subjected to greater resistance, and the tightening screws at the blade root could loosen, affecting the outer diameter of the blade crown and thus impacting product quality.

[0003] In summary, during the impeller assembly process of a certain gas turbine unit's power turbine guide vanes, the resistance to intermittent machining of the entire blade tip is relatively large, resulting in loosening of the fixation at the blade root, deviation of the blade tip arc dimension, and low yield. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that during the impeller assembly of a gas turbine unit's power turbine guide vanes, the resistance to intermittent turning of the entire blade tip is large, leading to loosening of the fixation at the blade root, deviation of the blade tip arc dimension, and low yield. This invention proposes a tooling for power turbine blade tip assembly and turning, as well as its usage method.

[0005] The present invention provides a tooling for tip fitting and turning of power turbine blades, comprising a process impeller, a pressure ring, multiple pressure plates, a connecting assembly for radial tensioning of tenons and grooves, and a blade crown fixing block.

[0006] The outer ring of the process impeller is provided with multiple irregularly shaped supports that are inclined from one side to the other. The bottom of the gap between two adjacent irregularly shaped supports forms a blade tenon groove, which is used to install blades. A connecting component for radial tensioning of the tenon groove is set at the bottom of the blade tenon groove to tighten the blade. The blade crown fixing block is used to position the blade crown of two adjacent blades. One side of each of the multiple irregularly shaped supports is connected to a connecting pressure ring, and the other side of each irregularly shaped support is connected to a pressure plate. The pressure plate is provided with square-headed cylindrical end set screws for tightening the blades.

[0007] Furthermore, the irregular support and the pressure ring are connected by hexagonal head screws.

[0008] Furthermore, the irregular support and pressure plate are connected by hexagonal head bolts.

[0009] Furthermore, the connecting assembly for radial tensioning of the tenon and groove includes a wedge, a wedge bolt, and a hexagonal nut;

[0010] The pressure ring has multiple holes that are oblique to the blade slot tenon groove. One end of the wedge bolt passes through the hole and is connected to the hexagonal nut located on the outside of the pressure ring. The other end of the wedge bolt is rotatably connected to the wedge block located at the bottom of the blade slot. The wedge bolt is used to drive the wedge block to move at the bottom of the blade slot, thereby tightening the blade.

[0011] Furthermore, a slanted washer fitted onto the wedge bolt is provided between the hexagonal nut and the pressure ring.

[0012] Method for using tooling for tip polishing and turning of power turbine blades

[0013] Step 1: Insert the blade into the tenon groove of the blade;

[0014] Step 2: Adjust the wedge bolt and hexagonal nut so that the wedge bolt pulls the wedge block, which in turn makes the wedge block press against the lower surface of the blade root to fix the blade.

[0015] Step 3: Adjust the hexagonal head bolts so that the pressure plate can rotate along the irregular support until one end of the pressure plate rotates to the blade tenon groove, and tighten the square head cylindrical end set screw to tighten the blade.

[0016] Step 4: Install leaf crown fixing blocks between each blade to circumferentially fix the leaf crowns of the blades;

[0017] Step 5: Machin the remaining material at the blade tip to achieve an intermittent depth of cut of 0.5 mm;

[0018] Step 6: When the blade is machined to a crown allowance of 0.2mm, the blade tip is finely ground using a grinding head mounted on the spindle of the vertical lathe.

[0019] Beneficial effects: This solution eliminates the previous step of casting rosin to fix the blade passages. Using this fixture, the blade root and tip are effectively fixed during the finishing process via radial tensioning of the tenon and groove connecting components. It ensures that even with large cuts and intermittent cutting to remove excess material from the blade tip, the fixation at the blade root remains relatively self-locking and will not loosen. This reduces assembly steps and time, improves production efficiency, and ensures the overall rigidity and fixation of the blade during turning. This solution avoids significant impacts on the final dimensional accuracy of the product from machining. Disassembly and reassembly of the fixture do not affect the strength and dimensions of the clamping structure. It is suitable for application to intermittent tip cutting of similar blade structures and can improve production efficiency. Attached Figure Description

[0020] Figure 1 A cross-sectional view of a tooling used for tip polishing and turning of power turbine blades;

[0021] Figure 2 for Figure 1 The P-direction view;

[0022] Figure 3 for Figure 1 Q-direction view;

[0023] Figure 4 A partial sectional view of the tooling used for tip polishing and turning of power turbine blades;

[0024] Figure 5 A view from direction A showing the mounting space for the process impeller tenon and the connecting assembly for radial tensioning of the tenon; Detailed Implementation

[0025] Specific implementation method 1: Tooling for tip fitting and turning of power turbine blades, which includes process impeller 1, pressure ring 5, multiple pressure plates 2, connecting assembly for radial tensioning of tenon groove and blade crown fixing block 11;

[0026] The outer ring of the process impeller 1 is provided with multiple irregularly shaped supports that are inclined from one side to the other. The bottom of the gap between two adjacent irregularly shaped supports forms a blade tenon groove. The blade tenon groove is used to install blades. The radial tensioning connection component of the tenon groove is set at the bottom of the blade tenon groove to tighten the blade. The blade crown fixing block 11 is used to position the blade crown of two adjacent blades. One side of each of the multiple irregularly shaped supports is connected to the connecting pressure ring 5, and the other side of each irregularly shaped support is connected to the pressure plate 2. The pressure plate 2 is provided with square-headed cylindrical end set screws 3 for tightening the blades.

[0027] In this embodiment: the radial tensioning connection assembly of the tenon groove applies a tightening force to the blade in the outward direction, ensuring the blade root is fixed and secure, and enhancing the self-locking property of the tightening structure. The pressure plate applies an axial tightening force to the blade.

[0028] Specific implementation method 2: Tooling for tip fitting and turning of power turbine blades, the irregular support and pressure ring 5 are connected by internal hexagonal head screws 6.

[0029] In this embodiment, the irregular support and the pressure ring are connected by hexagonal head screws, which facilitates disassembly and adjustment of the pressure ring.

[0030] Other implementation methods are the same as those in Specific Implementation Method 1.

[0031] Specific implementation method 3: Tooling for tip finishing and turning of power turbine blades, the irregular support and pressure plate 2 are connected by hexagonal head bolts 4.

[0032] In this embodiment, the irregular support and the pressure plate are connected by hexagonal head bolts, which facilitates disassembly and adjustment of the pressure plate, allowing the pressure plate to rotate along the hexagonal bolts.

[0033] Other implementation methods are the same as those in Specific Implementation Method 1.

[0034] Specific implementation method four: a tooling for tip fitting and turning of power turbine blades, the connecting assembly for radial tensioning of tenon grooves includes wedge block 7, wedge bolt 8 and hexagonal nut 10;

[0035] The pressure ring 5 has multiple holes that are oblique to the blade tenon groove. One end of the wedge bolt 8 passes through the hole and is connected to the hexagonal nut 10 located on the outside of the pressure ring 5. The other end of the wedge bolt 8 is rotatably connected to the wedge block 7 located at the bottom of the blade tenon groove. The wedge bolt 8 is used to drive the wedge block 7 to move at the bottom of the blade tenon groove, thereby tightening the blade.

[0036] In this embodiment: one end of the wedge bolt passes through the hole and connects to the hexagonal nut located on the outside of the pressure ring. The other end of the wedge bolt is used to connect the wedge block, keeping the hexagonal nut stationary. After the wedge bolt rotates, its position can be adjusted, causing the wedge block to tighten the bottom of the blade. The radial tensioning connection assembly of the tenon groove, through the axial movement of the wedge bolt, pushes the wedge block to exert a tightening force on the blade in the outward direction, ensuring the fixed tightness at the blade root and enhancing the self-locking property of the tightening structure. The pressure plate applies an axial tightening force to the blade.

[0037] Other implementation methods are the same as those in Specific Implementation Method 1.

[0038] Specific implementation method five: a tooling for the tip fitting and turning of power turbine blades, wherein a hexagonal nut 10 and a pressure ring 5 are provided with a slanted washer 9 fitted on a wedge bolt 8.

[0039] In this embodiment, a slanted washer fitted on the wedge bolt is provided between the hexagonal nut and the pressure ring to fill the gap between the pressure ring and the hexagonal nut, so that the hexagonal nut connection is stable.

[0040] Other implementation methods are the same as those in Specific Implementation Method Four.

[0041] Specific Implementation Method Seven: Method for using tooling for tip finishing and turning of power turbine blades

[0042] Specific Implementation Method Six: A method for using a tooling fixture for tip finishing and turning of power turbine blades, characterized in that:

[0043] Step 1: Insert the blade into the tenon groove of the blade;

[0044] Step 2: Adjust the wedge bolt 8 and hexagonal nut 10 so that the wedge bolt 8 pulls the wedge block 7, thereby causing the wedge block 7 to press against the lower surface of the blade root and fix the blade.

[0045] Step 3: Adjust the hexagonal head bolt 4 so that the pressure plate 2 can rotate along the irregular support until one end of the pressure plate 2 rotates to the blade tenon groove, and tighten the square head cylindrical end set screw 3 to tighten the blade.

[0046] Step 4: Install the leaf crown fixing block 11 between each blade to fix the leaf crown of the blade circumferentially;

[0047] Step 5: Machin the remaining material at the blade tip to achieve an intermittent depth of cut of 0.5 mm;

[0048] Step Six: When the blade is machined to a crown allowance of 0.2mm, the blade tip is precision ground using a grinding head mounted on the vertical lathe spindle. Working Principle:

[0049] During the impeller assembly process of the power turbine guide vanes in a gas turbine unit, the entire blade tip needs to be machined. Because the blades are crown-structured, the intermittent machining process presents significant resistance, necessitating control to prevent loosening at the blade root during machining to ensure precise dimensional accuracy of the blade tip arc. A process wheel is designed for fixing the power turbine blade root, combined with multiple crown fixing blocks, to ensure the overall rigidity and fixation of the blade during machining.

Claims

1. A tooling for tip finishing and turning of power turbine blades, characterized in that: It includes a process impeller (1), a pressure ring (5), multiple pressure plates (2), a tenon radial tensioning connection assembly, and a crown fixing block (11). The outer ring of the process impeller (1) is provided with multiple irregular support platforms that are inclined from one side to the other. The bottom of the gap between two adjacent irregular support platforms forms a blade tenon groove. The blade tenon groove is used to install blades. The radial tensioning connection component of the tenon groove is set at the bottom of the blade tenon groove to tighten the blades. The blade crown fixing block (11) is used to position the blade crowns of two adjacent blades. One side of each of the multiple irregular support platforms is connected to the connecting pressure ring (5), and the other side of each irregular support platform is connected to the pressure plate (2). The pressure plate (2) is provided with square-headed cylindrical end set screws (3) for tightening the blades. The connecting assembly for radial tensioning of the tenon and groove includes a wedge (7), a wedge bolt (8), and a hexagonal nut (10); The pressure ring (5) has multiple holes that are oblique to the blade slot tenon groove. One end of the wedge bolt (8) passes through the hole and is connected to the hexagonal nut (10) located on the outside of the pressure ring (5). The other end of the wedge bolt (8) is rotatably connected to the wedge block (7) located at the bottom of the blade tenon groove. The wedge bolt (8) is used to drive the wedge block (7) to move at the bottom of the blade tenon groove and thus tighten the blade.

2. The tooling for tip finishing and turning of power turbine blades according to claim 1, characterized in that: The irregular support and pressure ring (5) are connected by internal hexagonal head screws (6).

3. The tooling for tip finishing and turning of power turbine blades according to claim 1, characterized in that: The irregular support and pressure plate (2) are connected by hexagonal head bolts (4).

4. The tooling for tip finishing and turning of power turbine blades according to claim 1, characterized in that: A hexagonal nut (10) and a pressure ring (5) are provided with a slanted washer (9) fitted on a wedge bolt (8).

5. A method of using the tooling according to any one of claims 1-4, characterized in that: Step 1: Insert the blade into the tenon groove of the blade; Step 2: Adjust the wedge bolt (8) and hexagonal nut (10) so that the wedge bolt (8) pulls the wedge block (7), thereby making the wedge block (7) press against the lower surface of the blade root to fix the blade; Step 3: Adjust the hexagonal head bolt (4) so ​​that the pressure plate (2) can rotate along the irregular support until one end of the pressure plate (2) rotates to the blade tenon groove, and tighten the square head cylindrical end set screw (3) to tighten the blade; Step 4: Install leaf crown fixing blocks (11) between each leaf to fix the leaf crown of the leaf in a circumferential manner; Step 5: Machin the remaining material at the blade tip to achieve an intermittent depth of cut of 0.5 mm; Step 6: When the blade is machined to a crown allowance of 0.2mm, the blade tip is finely ground using a grinding head mounted on the spindle of the vertical lathe.

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