Low-pressure turbine rotor balancing device, balancing test method and special bearing machining method

Abstract

This invention discloses a low-pressure turbine rotor balancing device, a balancing test method, and a method for machining a special bearing. The balancing device includes a first positioning clamping component and a second positioning clamping component. The first clamping component includes a special bearing inner ring, which comprises an inner hole that mates with the low-pressure turbine rotor journal, an inner hole stepped surface that mates with the axial end face of the low-pressure turbine rotor journal, a surface raceway that mates with the balls of a standard self-aligning ball bearing, and a cylindrical surface located outside the inner hole of a first bearing housing for adjusting the imbalance of the special bearing inner ring. During the balancing test, the outer circular surface of the low-pressure turbine rotor journal mates with the inner hole of the special bearing inner ring, and the axial end face of the journal is positioned with the inner hole stepped surface of the special bearing inner ring. Axial locking is achieved with double nuts, and axial and radial positioning is achieved by the second positioning clamping component mates with the inner hole of the low-pressure turbine rotor bearing. This invention meets the clamping and fixing requirements for low-pressure turbine rotor balancing tests, is low in cost, and easy to implement.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine parts manufacturing technology, specifically low-pressure turbine rotor balancing device, balancing test method and special bearing processing method. Background Technology

[0002] Low-pressure turbine rotors are an important type of component in aero-engines, and balancing tests are one of the key tests for these components. Figure 1 As shown in the figure, the outline of the low-pressure turbine rotor is drawn with a double-dotted line. During the balancing test, the bearing is one of the key components in the balancing device. However, standard bearings purchased from the market cannot meet the clamping and positioning requirements of the low-pressure turbine rotor. Therefore, it is necessary to design, manufacture, and replace bearings with special parts to meet the usage requirements. Summary of the Invention

[0003] The present invention aims to provide a low-pressure turbine rotor balancing device, a balancing test method, and a special bearing processing method. The balancing device is designed according to the low-pressure turbine rotor and the balancing machine. It is used to clamp the journal, position the axial direction of the low-pressure turbine rotor, and fix it on the balancing machine for balancing test, so as to meet the requirements of the low-pressure turbine rotor balancing test. Furthermore, the special bearing has a relatively low processing cost and a relatively simple processing method, and does not need to be customized by the bearing manufacturer.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A low-pressure turbine rotor balancing device includes a first positioning and clamping component connected to the journal of the low-pressure turbine rotor, and a second positioning and clamping component connected to the inner bore of the low-pressure turbine rotor bearing, wherein:

[0006] The first positioning and clamping component includes a first bearing housing, the circumferential surface of which has a mounting groove for positioning with the balancing machine, a self-aligning ball bearing standard part without an inner ring installed in the inner hole of the first bearing housing, the inner ring position of the self-aligning ball bearing standard part is replaced with a special bearing inner ring, and the axial end face of the first bearing housing is connected to a bearing pressure ring for pressing the self-aligning ball bearing standard part.

[0007] The inner ring of the special bearing includes an inner hole that mates with the journal of the low-pressure turbine rotor, an inner hole stepped surface that mates with the axial end face of the journal of the low-pressure turbine rotor, a surface raceway that mates with the balls of the self-aligning ball bearing standard part, and a cylindrical surface located outside the inner hole of the first bearing housing for adjusting the imbalance of the inner ring of the special bearing.

[0008] The second positioning and clamping component includes a second bearing housing. The circumferential surface of the second bearing housing has a mounting groove for positioning with the balancing machine. A bearing housing spindle that is inserted into the inner hole of the low-pressure turbine rotor bearing is installed in the inner hole of the second bearing housing. A bearing housing bushing is installed at the end of the bearing housing spindle. The end of the bearing housing spindle is engaged with the inner hole of the low-pressure turbine rotor bearing through the bearing housing bushing.

[0009] Furthermore, the low-pressure turbine rotor balancing device also includes: a first clamping nut and a second clamping nut, the first clamping nut and the second clamping nut being connected to the external thread on the shaft surface on one side of the low-pressure turbine rotor journal, and the first clamping nut or the second clamping nut being pressed against the end face of the inner ring of the special bearing located outside the first bearing seat.

[0010] Furthermore, the low-pressure turbine rotor balancing device also includes a dedicated hexagonal bolt, which passes through the second bearing housing and points towards the low-pressure turbine rotor bearing. The dedicated hexagonal bolt is used to disassemble the bearing housing spindle. By rotating the dedicated hexagonal bolt, the low-pressure turbine rotor bearing is tightened, thereby separating the bearing housing spindle from the inner hole of the low-pressure turbine rotor bearing.

[0011] A method for machining the aforementioned special bearing inner ring includes the following steps:

[0012] Step 1: Disassemble the standard self-aligning ball bearing components, remove the inner ring, and retain the balls, ball cage, and outer ring;

[0013] Step 2: Obtain the parameters of the self-aligning ball bearing standard parts obtained in Step 1, including the ball diameter Φd, the center distance of the inner ring bearing raceway C, the outer diameter of the inner ring ΦD1, the inner ring raceway R value, the nominal width of the bearing B, and the outer ring raceway diameter ΦM value.

[0014] Step 3: Based on the parameters of the self-aligning ball bearing standard parts obtained in Step 2, calculate the outer diameter ΦD2 of the inner ring raceway of the special bearing.

[0015] Step 4: Machine the inner ring of the special bearing according to the outer diameter Φd2 of the low-pressure turbine rotor journal, the outer diameter ΦD2 of the raceway of the special bearing inner ring, the center distance C of the raceway of the inner ring bearing, the ball diameter Φd, and the nominal width B of the bearing.

[0016] Step 5: Perform a dynamic balancing test on the machined special bearing inner ring. By removing the material from the cylindrical surface of the special bearing inner ring used to adjust the imbalance, the required imbalance amount is obtained.

[0017] Step six: Assemble the inner ring of the special bearing that meets the unbalance requirements in step five with the balls, ball cage and outer ring of the self-aligning ball bearing standard part in step one.

[0018] Alternatively, in step three, the final value of the outer diameter ΦD2 of the inner ring raceway of the special bearing is obtained by subtracting a certain amount of movement from the calculated outer diameter ΦD2 of the inner ring raceway of the special bearing in step four.

[0019] Alternatively, in step four, the machining steps for the special bearing inner ring include:

[0020] Step 1: Using bar stock, machine all surfaces with a one-sided allowance. All surfaces include the end face, inner hole, and outer cylindrical surface of the special bearing inner ring.

[0021] Step two: Grind the two end faces of the inner ring of the special bearing using a grinding machine to grind the axial length.

[0022] Step 3: Deburr and round off sharp edges;

[0023] Step four: Quenching and tempering;

[0024] Step 5: Grind the two end faces of the inner ring of the special bearing along its axial length again, leaving a single-sided allowance;

[0025] Step 6: Grind the inner bore of the special bearing and the corresponding end faces, leaving a single-sided allowance on each face;

[0026] Step 7, manual processing time;

[0027] Step 8: Grind the two end faces of the inner ring of the special bearing along its axial length again, leaving a single-sided allowance;

[0028] Step nine, turn blue;

[0029] Step 10: Grind the two end faces of the inner ring of the special bearing along its axial length again;

[0030] Step 11: Precision grind all surfaces of the inner hole and corresponding end faces of the inner ring of the special bearing;

[0031] Step 12: Grind the outer surface and corresponding end faces of the inner ring of the special bearing.

[0032] Step thirteen: Balance test. Remove the material from the cylindrical surface of the inner ring of the special bearing used to adjust the imbalance to obtain the required imbalance.

[0033] The low-pressure turbine rotor balancing test method uses the aforementioned balancing device and includes:

[0034] The low-pressure turbine rotor is mated with the outer circular surface of the journal and the inner hole of the special bearing. The axial end face of the journal is positioned with the stepped surface of the inner hole of the special bearing. The low-pressure turbine rotor is axially locked by the first clamping nut, the second clamping nut, the external thread on the shaft surface of one side of the journal and the end face of the special bearing. The rotor is positioned and clamped by the mounting groove on the first bearing seat.

[0035] Axial and radial positioning is achieved by the bearing housing bushing engaging with the inner bore of the low-pressure turbine rotor bearing, and positioning and clamping are achieved by the mounting groove on the second bearing housing with the balancing machine.

[0036] Compared with existing technologies, this invention provides a low-pressure turbine rotor balancing device, and also provides a method for calculating and machining the inner ring of a special bearing in the balancing device. The low-pressure turbine rotor balancing device machined according to this method has been tested and verified in field use after being used in balancing tests of low-pressure turbine rotors. All parameters have ensured the balancing test requirements of low-pressure turbine rotors. On the other hand, the special bearing machining method of this invention is low-cost, easy to implement, and does not require custom production by bearing manufacturers. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the balancing device;

[0038] Figure 2 for Figure 1 Schematic diagram of the dedicated bearing at the left end;

[0039] Figure 3 for Figure 2 Schematic diagram of the inner ring of a special-purpose bearing;

[0040] Figure 4 This is a schematic diagram of a standard self-aligning ball bearing.

[0041] Figure 5 Drawings for calculating the inner ring of a special bearing;

[0042] In the diagram: 1-Second bearing housing, 2-Bearing housing spindle, 3-Bearing housing bushing, 4-First bearing housing, 5-Special bearing inner ring, 6-Bearing pressure ring, 7-First clamping nut, 8-Second clamping nut, 9-Self-aligning ball bearing standard part, 10-Hex head bolt, 11-Slotted countersunk screw, 12-Special hex bolt. Detailed Implementation

[0043] The present invention will be further described below with reference to specific embodiments, but it should not be construed as limiting the scope of the subject matter of the present invention to the following embodiments. All modifications, substitutions and alterations made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention are included within the scope of the present invention.

[0044] like Figure 1As shown, the low-pressure turbine rotor balancing device comprises two parts. One part is a left-end positioning and clamping component consisting of a first bearing housing 4, a special bearing inner ring 5, a bearing retaining ring 6, a first clamping nut 7, a second clamping nut 8, a self-aligning ball bearing standard part 9, and hexagonal head bolts 10. The other part is a right-end positioning and clamping component consisting of a second bearing housing 1, a bearing housing spindle 2, a bearing housing bushing 3, slotted countersunk screws 11, and special hexagonal head bolts 12. The hexagonal head bolts 10 are used to fix the bearing retaining ring 6 to the end face of the first bearing housing 4, thereby clamping the self-aligning ball bearing standard part 9 and the special bearing inner ring 5. The slotted countersunk screws 11 are used to connect the bearing housing bushing 3 and the bearing housing spindle 2. The special hexagonal head bolts 12 are evenly distributed throughout the second bearing housing 1, and the bearing housing spindle 2 is pushed out of the low-pressure turbine rotor bearing inner hole through the threads. The bearing housing spindle 2 is axially limited with the second bearing housing 1 by the stepped surface at its end.

[0045] Figure 2 This demonstrates a special bearing assembled using standard self-aligning ball bearing part 9 and a special bearing inner ring 5. The machining method for this special bearing is as follows:

[0046] Buy Figure 4 The self-aligning ball bearing standard part 9 shown is a cylindrical bore self-aligning ball bearing, type 1318, conforming to standard GB / T281-1994;

[0047] Disassembly Figure 4 The self-aligning ball bearing standard part 9 shown is arranged according to the balls, inner ring, outer ring and ball cage;

[0048] Measurement Figure 4 The self-aligning ball bearing standard part 9 shown has the following relevant parameters: ball diameter Φd, inner ring bearing raceway center distance C, inner ring outer diameter ΦD1, inner ring raceway R, outer ring diameter ΦM, etc.

[0049] calculate Figure 3 The raceway outer diameter ΦD2 of the inner ring 5 of the special bearing shown is obtained by subtracting the movement amount of 0.05mm from the calculated value of the raceway outer diameter ΦD2 as required.

[0050] prepared by Figure 3 The machining process for the inner ring 5 of the special bearing shown is as follows: prepare raw materials and organize production according to the machining process.

[0051] Equilibrium test, in accordance with the requirements of the equilibrium test. Figure 3 Remove material from the W-face to ensure that the imbalance of the inner ring 5 of the machined special bearing is, for example, 3 g.mm;

[0052] The balls, outer ring, and ball cage of the self-aligning ball bearing standard part 9 are assembled with the inner ring 5 of the special bearing to obtain the special bearing. After quality inspection, it is delivered for use.

[0053] Calculation and machining method of the inner ring 5 of the special bearing in the balancing device:

[0054] (1) Measurement Figure 4 The ball diameter Φd in the standard part 9 of the self-aligning ball bearing shown is... Figure 3 The inner ring bearing raceway center distance C, inner ring outer diameter ΦD1, and inner ring raceway R value are shown.

[0055] (2) Calculation Figure 3 The outer diameter ΦD2 value of the inner ring 5 of the special bearing is based on... Figure 3 Technical condition 3 requires that the corrected values ​​be added to the machining drawings for the inner ring 5 of the special bearing. Figure 3 The technical requirements are as follows:

[0056] 1. ΦD1 is manufactured according to the measured dimensions of the inner ring of the ball bearing.

[0057] 2. ΦD2, C, and R are manufactured according to the average value of the actual measured inner ring raceway dimensions of the ball bearing.

[0058] 3. Fine-tune ΦD2 to correct the diameter movement, with an allowable movement of 0.03~0.06mm.

[0059] 4. The runout of the two raceways R relative to ΦA is 0.005max.

[0060] 5. The parallelism between the two raceways R is 0.005.

[0061] 6. The runout of the remaining surfaces relative to ΦA is 0.1.

[0062] 7. Remove material from the W side to ensure that the part imbalance is 3g.mm.

[0063] In the axial direction of the inner ring of the self-aligning ball bearing standard part 9 (i.e., in the direction of the nominal width B of the bearing), the outer diameter of the inner ring is measured at three sections and recorded as Φd1, Φd2, and Φd3. The average value is then calculated according to the following formula to determine the outer diameter. Figure 3 The value of ΦD1 is used to obtain the machining drawing value of the inner ring 5 of the special bearing;

[0064] ΦD1=(Φd1+Φd2+Φd3) / 3;

[0065] (3) Measure and record the diameter Φd of the ball bearings. The diameter difference of each row of balls should be no more than 0.002 mm.

[0066] (4) Measurement Figure 4The values ​​of ΦD and ΦM on the outer ring of the self-aligning ball bearing standard part 9 are shown. ΦD is used for machining to fit with the inner hole of the first bearing housing 4 (this value is used as the outer diameter of the inner ring of the special bearing inner ring ΦD1) to ensure the interference fit requirement between the outer ring of the self-aligning ball bearing standard part 9 and the inner hole of the first bearing housing 4.

[0067] (5) Calculate and determine based on the center distance C of the inner ring bearing raceway, the R value of the inner ring raceway, and the outer ring diameter ΦM. Figure 3 The outer diameter ΦD2 value of the inner ring 5 of the special bearing;

[0068] The calculation process is as follows, such as Figure 5 As shown:

[0069] In right triangle OAB: AC = AB - BC;

[0070]

[0071] Given: OA = C / 2, BC = Φd / 2, OB = (ΦM - Φd) / 2.

[0072] Substituting it into the equation, we can find:

[0073] (6) Press Figure 3 As required by technical condition 3, the calculated value of the outer diameter ΦD2 of the inner ring 5 of the special bearing is reduced by 0.05mm before being applied to the machining drawings;

[0074] (7) Compile the machining process for the inner ring 5 of the special bearing, as follows:

[0075] 1) Horizontal lathe: Using bar stock, machine all surfaces (including...) Figure 3 The stepped inner hole of the inner ring 5 of the special bearing, the stepped surface of the inner hole, the two axial end faces of the inner ring 5 of the special bearing, and the outer circular surface of the inner ring 5 of the special bearing, each surface is left with a single-sided allowance for grinding.

[0076] 2) Surface grinding: Grind the two end faces of the inner ring of the special bearing along the axial length 5 on a surface grinder, leaving 0.4mm on each side to ensure the parallelism of the two end faces;

[0077] 3) Horizontal machining center: Alignment and... Figure 3 Drill 4-Φ8 holes on the outer circular surface of the left end; this step is optional.

[0078] 4) Fitter: Deburring, rounding sharp edges;

[0079] 5) Heat treatment: After quenching and tempering, ensure that the surface hardness meets HRC58-64;

[0080] 6) Surface grinding: Grind the two end faces of the inner ring of the special bearing along the axial length of 5 on a surface grinder, leaving a single-sided allowance to ensure the parallelism of the two end faces;

[0081] 7) Precision internal grinding: Precision grinding of all surfaces of the inner hole of the inner ring 5 of the special bearing and the corresponding end faces, with a single-sided allowance remaining on each surface;

[0082] 8) Artificial aging treatment;

[0083] 9) Surface grinding: Grind the two end faces of the inner ring of the special bearing along the axial length of 5 on a surface grinder, leaving a single-sided allowance to ensure the parallelism of the two end faces;

[0084] 10) Turns blue;

[0085] 11) Fitter: Grind the two end faces of the inner ring of the special bearing along the axial length 5 to meet the parallelism and flatness requirements of the two end faces in the drawing;

[0086] 12) Precision internal grinding: Grind all surfaces of the inner hole of the inner ring 5 of the special bearing and the corresponding end faces (including the stepped surface that mates with the axial end face of the journal) to ensure that the cylindricity and runout of the inner hole that mates with the journal meet the requirements.

[0087] 13) CNC external grinding: Grinding the outer cylindrical surface and corresponding end face of the inner ring 5 of a special bearing to ensure... Figure 3 Technical requirements 4 and 5;

[0088] 14) Equilibrium test: according to Figure 3 The technical requirements shown in section 7 are as follows: Figure 3 Remove material from the W-side to ensure an imbalance of 3 g / mm.

[0089] (10) Prepare raw materials according to the above process and organize the production of special bearing inner ring 5;

[0090] (11) Quality inspection and delivery for subsequent assembly of special bearings.

[0091] The method for low-pressure turbine rotor balancing test is as follows:

[0092] like Figure 1 As shown, the special bearing is assembled from the left side of the low-pressure turbine rotor, and connected to the low-pressure turbine rotor journal Φd2. Figure 3 The inner ring 5 of the special bearing shown is positioned in accordance with the inner hole ΦA. The low-pressure turbine rotor is axially locked by the first clamping nut 7, the second clamping nut 8, the external thread on the shaft surface on one side of the low-pressure turbine rotor journal, and the end face of the inner ring 5 of the special bearing. The positioning and clamping fixation between the bearing and the balancing machine is achieved by the mounting groove with a width of H1 and an outer diameter of Φd on the first bearing seat 4.

[0093] Axial and radial positioning is achieved by the outer diameter Φd1 and end face of the bearing housing bushing 3 engaging with the inner hole of the bearing at the right end of the low-pressure turbine rotor; positioning and clamping are achieved with the balancing machine through the mounting groove on the second bearing housing 1 with a width of H and an outer diameter of Φd.

[0094] Contents not described in detail in this specification are prior art known to those skilled in the art. Although illustrative specific embodiments of the invention have been described above to facilitate understanding by those skilled in the art, it should be understood that the invention is not limited to the scope of the specific embodiments. Various modifications are readily apparent to those skilled in the art as long as they fall within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of this invention are protected.

Claims

1. A low-pressure turbine rotor balancing device, characterized in that: It includes a first positioning and clamping component connected to the journal of the low-pressure turbine rotor, and a second positioning and clamping component connected to the inner bore of the low-pressure turbine rotor bearing, wherein: The first positioning and clamping component includes a first bearing housing (4), the circumferential surface of the first bearing housing (4) has a mounting groove for positioning with the balancing machine, a self-aligning ball bearing standard part (9) without an inner ring is installed in the inner hole of the first bearing housing (4), the inner ring position of the self-aligning ball bearing standard part (9) is replaced with a special bearing inner ring (5), and the axial end face of the first bearing housing (4) is connected to a bearing pressure ring (6) for pressing the self-aligning ball bearing standard part (9); The inner ring (5) of the special bearing includes an inner hole that mates with the journal of the low-pressure turbine rotor, an inner hole stepped surface that mates with the axial end face of the journal of the low-pressure turbine rotor, a surface raceway that mates with the balls of the self-aligning ball bearing standard part (9), and a cylindrical surface located outside the inner hole of the first bearing seat (4) for adjusting the imbalance of the inner ring (5) of the special bearing. The second positioning and clamping component includes a second bearing housing (1). The circumferential surface of the second bearing housing (1) has a mounting groove for positioning with the balancing machine. A bearing housing spindle (2) that is inserted into the inner hole of the low-pressure turbine rotor bearing is installed in the inner hole of the second bearing housing (1). A bearing housing bushing (3) is installed at the end of the bearing housing spindle (2). The end of the bearing housing spindle (2) is engaged with the inner hole of the low-pressure turbine rotor bearing through the bearing housing bushing (3).

2. The low-pressure turbine rotor balancing device according to claim 1, characterized in that, Also includes: The first clamping nut (7) and the second clamping nut (8) are connected to the external thread on the shaft surface on one side of the low-pressure turbine rotor journal, and the first clamping nut (7) or the second clamping nut (8) is pressed on the end face of the inner ring (5) of the special bearing located outside the first bearing seat (4).

3. The low-pressure turbine rotor balancing device according to claim 1, characterized in that, It also includes a special hex bolt (12) that passes through the second bearing housing (1) and points toward the low-pressure turbine rotor bearing.

4. A method for machining the inner ring of a special bearing as described in claim 1, characterized in that, Includes the following steps: Step 1: Disassemble the standard part (9) of the self-aligning ball bearing, remove the inner ring, and keep the balls, ball cage and outer ring; Step 2: Obtain the parameters of the self-aligning ball bearing standard part (9) from Step 1, including the ball diameter Φd, the inner ring bearing raceway center distance C, the inner ring outer diameter ΦD1, the inner ring raceway R value, the bearing nominal width B, and the outer ring raceway diameter ΦM value. Step 3: Based on the parameters of the self-aligning ball bearing standard part (9) obtained in Step 2, calculate the outer diameter ΦD2 of the raceway of the inner ring (5) of the special bearing. Step 4: Based on the outer diameter Φd2 of the low-pressure turbine rotor journal, the outer diameter ΦD2 of the raceway of the special bearing inner ring (5), the center distance C of the inner ring bearing raceway, the ball diameter Φd, and the nominal width B of the bearing, the special bearing inner ring (5) is machined. Step 5: Perform a dynamic balancing test on the processed special bearing inner ring (5). By removing the material from the cylindrical surface of the special bearing inner ring (5) used to adjust the imbalance, the required imbalance amount is obtained. Step six, the special bearing inner ring (5) that meets the unbalance requirement in step five is used as the bearing inner ring and assembled with the balls, ball cage and outer ring of the self-aligning ball bearing standard part (9) in step one.

5. The machining method for the inner ring of the special bearing according to claim 4, characterized in that: In step three, the final value of the outer diameter ΦD2 of the raceway of the inner ring (5) of the special bearing is obtained by subtracting a certain amount of movement from the calculated outer diameter ΦD2 of the raceway of the inner ring (5) of the special bearing in step four.

6. The machining method for the inner ring of the special bearing according to claim 4, characterized in that: In step four, the machining steps for the inner ring (5) of the special bearing include: Step 1: Using bar stock, machine all surfaces and leave a single-sided allowance. All surfaces include the end face, inner hole and outer cylindrical surface of the special bearing inner ring (5). Step 2: Grind the two end faces of the inner ring (5) of the special bearing using a grinding machine to grind the axial length of the bearing. Step 3: Deburr and round off sharp edges; Step four: Quenching and tempering; Step 5: Grind the two end faces of the inner ring (5) of the special bearing (5) along its axial length again, leaving a single-sided allowance; Step 6: Grind the inner hole of the special bearing inner ring (5) and the corresponding end face, leaving a single-sided allowance on each face; Step 7, manual processing time; Step 8: Grind the two end faces of the inner ring (5) of the special bearing (5) along its axial length again, leaving a single-sided allowance; Step nine, turn blue; Step 10: Grind the two end faces of the inner ring (5) of the special bearing along its axial length again; Step 11: Grind the inner bore surfaces and corresponding end faces of the special bearing inner ring (5); Step 12: Grind the outer circle and corresponding end faces of the inner ring (5) of the special bearing. Step 13, balance test: remove the material from the cylindrical surface of the inner ring (5) of the special bearing used to adjust the unbalance, and obtain the unbalance that meets the requirements.

7. A method for balancing low-pressure turbine rotors, characterized in that, The balancing device according to claim 2 is used, and includes: The low-pressure turbine rotor journal outer circular surface is fitted with the inner hole of the special bearing inner ring (5), the axial end face of the journal is positioned with the inner hole step surface of the special bearing inner ring (5), the low-pressure turbine rotor is axially locked by the first clamping nut (7), the second clamping nut (8) and the external thread of the shaft surface on one side of the low-pressure turbine rotor journal and the end face of the special bearing inner ring (5), and the low-pressure turbine rotor is positioned and clamped by the mounting groove on the first bearing seat (4) with the balancing machine. Axial and radial positioning is achieved by the bearing housing bushing (3) engaging with the inner bore of the low-pressure turbine rotor bearing, and positioning and clamping are achieved by the mounting groove on the second bearing housing (1) with the balancing machine.

Images