Heavy gas turbine blade tip clearance measuring and adjusting method

Abstract

The invention aims to provide a heavy gas turbine blade tip clearance measuring and adjusting method, and belongs to the field of measuring methods. According to the method, the most accurate blade tip clearance of the heavy-duty gas turbine can be measured in shorter time and less operation. The measuring and adjusting method can ensure that the casing does not deform in the measuring process, and more accurate blade tip clearance is obtained. The rotor does not need to be repeatedly hoisted in the adjusting process, and axial displacement can be conducted on the rotor through the jack. As the heavy gas turbine is heavy, a special jacking frame is arranged to prevent a rotor and a casing from being damaged by jacking force. The gap measurement of each part of the rotor is carried out under the condition of fully ensuring the measurement precision, and a relatively accurate actual value can be obtained. The influence of inconvenient hoisting of the heavy gas turbine rotor on clearance measurement and adjustment is improved, the hoisting process is greatly reduced, and the workload of personnel and the project construction period are reduced.

Description

Technical Field

[0001] The present invention relates to a gas turbine measurement method, in particular to a method for measuring the re-ignition blade tip clearance. Background Art

[0002] During the assembly of heavy-duty gas turbines, the most important thing to ensure the quality of the turbine is to control the dimensions of the turbine within the design range. The tip clearance (including the clearance between the blade tip and the casing, and between the blade tip and the rotor) is the most extensive, most complex, and most important measurement among all dimensions. Qualified tip clearance must meet the requirements of the drawing for the dimensions of each part, the design requirements for the installation steps, and the measurement methods and tools for the measurement requirements.

[0003] With the rapid development of gas turbine assembly technology, measurement technology is also constantly improving. The measurement and adjustment of gas turbines is an important part of ensuring their performance, economic efficiency, and environmental protection. The continuous improvement of measurement and adjustment methods provides strong support for the optimization and upgrading of gas turbines. The measurement and adjustment of the tip clearance of gas turbines is an important step to ensure the normal operation of gas turbines. Too large or too small a clearance will have an adverse effect on the performance of the gas turbine, and even cause failure. Heavy gas turbines have more factors to consider in measurement and adjustment due to their heavy weight, long machine length, and difficulty in lifting. Therefore, accurate measurement and reasonable adjustment of the tip clearance are crucial. Summary of the invention

[0004] The object of the present invention is to provide a heavy-duty gas turbine blade tip clearance measurement and adjustment method which can ensure that the casing is not deformed during the measurement process, thereby obtaining a more accurate blade tip clearance.

[0005] The object of the present invention is achieved in that:

[0006] The present invention provides a method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine, which is characterized by comprising the following steps:

[0007] (1) Install the horizontal adjustable support tooling;

[0008] (2) Adjust the force on the receiver so that everything is in a horizontal state;

[0009] (3) Disassemble the upper casing and install the rotor;

[0010] (4) Measure the axial movement of the rotor;

[0011] (5) Install the gasket to determine the rotor position;

[0012] (6) Confirm the rotor position;

[0013] (7) Measure the blade tip clearance.

[0014] The present invention may also include:

[0015] 1. The specific process of step (1) is as follows:

[0016] A. Install the horizontal adjustable support fixtures of the receiver at the bottom of each receiver, set a jack between the receiver and the fixture, and install it vertically on the foundation;

[0017] B. Fix the dial indicator on the adjustable horizontal support fixture of the receiver, set jacks at six locations under the receiver, tighten all jacks toward the receiver, and set all dial indicator readings to 0.

[0018] 2. The specific process of step (2) is as follows:

[0019] a. Use a No. 2 jack to lift the flange joint between the turbine housing and the exhaust casing by 0.06 to 0.10 mm, and record all dial indicator readings;

[0020] b. Use No. 3 jack to push the flange joint between the diffuser casing and the turbine casing to 0.08-0.10mm, and record all dial indicator readings;

[0021] c. Use a No. 4 jack to lift the flange joint of the intermediate casing and the diffuser casing by 0.10 to 0.12 mm, and record all dial indicator readings;

[0022] d. Use a No. 5 jack to lift the middle part of the middle casing by 0.02 to 0.04 mm and record all dial indicator readings;

[0023] e. Use a No. 6 jack to lift the rear side of the intake casing by 0 to 0.01 mm and record all dial indicator readings.

[0024] 3. The specific process of step (3) is as follows:

[0025] I. Separate the upper exhaust casing, turbine casing, mid-expansion casing, inner barrel, and intake casing, and confirm that the casing is in a horizontal state by ensuring the values ​​of the dial indicators on the six jacks below the casing;

[0026] II. Lift the rotor and place it on the lower casing. Read the dial indicator value to confirm that the casing is still in a completely horizontal state.

[0027] III. The rotor position changes according to the thickness of the intake side bearing gasket.

[0028] 4. The specific process of step (4) is as follows:

[0029] i. Install process bushings in the upstream and downstream bearing seats, with thicknesses of H1 and H2 respectively, to prevent damage to the bearings during the process of pressing the rotor; place a micrometer on the rotor intake side, with the dial facing the rotor end face, the horizontal position of the dial at the middle dividing surface of the casing, and the reading is zero;

[0030] ii. Fix the thrust measuring fixture on the intake casing at the position close to the compressor wheel on the middle plane of the intake casing, place the hydraulic jack between the fixture and the wheel, one on each side, pressurize the hydraulic jack, and push the rotor completely to the intake side; release the hydraulic jack and return the dial gauge to zero again;

[0031] iii. Install the intake side bearing seat, place the hydraulic jack between the rotor flange surface and the end face of the No. 1 bearing seat (, pressurize the hydraulic jack, and push the rotor completely to the exhaust side. After the pressure reaches the requirement, gradually reduce the pressure. After the dial gauge reading stabilizes, record the dial gauge reading at this time. The reading is the axial displacement of the rotor in the casing;

[0032] iv. Remove the hydraulic jack, put it back to the downstream side, pressurize the hydraulic jack, and gradually reduce the pressure after the pressure reaches the requirement, and record the reading of the dial gauge at this time;

[0033] v. Repeat the above steps at least 3 times until the value is stable, and calculate the average value M of the measured value of the rotor axial displacement based on the stable value.

[0034] 5. The specific process of step (5) is as follows:

[0035] ① Dimension A is the distance between the secondary partition and the casing. The position of the rotor relative to the casing is determined by determining the value of dimension A;

[0036] ② The thickness of the process bushing on the downstream side is H2, and the thickness of the process bushing on the upstream side is H1. Measure the actual value A of the axial clearance between the turbine 2nd stage diaphragm and the rotor; if the actual value of dimension A exceeds the specified range, calculate the thickness of the bushing according to the table, and adjust the bushing thickness to make dimension A meet the design requirements;

[0037] ③ Disassemble the bearing seat, replace the process bushing with the calculated and ground formal bushing, install the bearing seat, and measure the actual value A of the axial clearance between the turbine 2nd stage partition and the rotor. If it is unqualified, continue to adjust and replace the bushing thickness until it is qualified.

[0038] 6. The specific process of step (6) is as follows: install the bushing, repeatedly press the rotor, confirm that the A dimension is between 9.40-9.70, and M is between 0.35-0.50. At this time, the rotor position is the measurement position that meets the requirements.

[0039] 7. The specific process of step (7) is as follows:

[0040] Measure the compressor blade tip clearance, including the stationary blade tip clearance S and the moving blade tip clearance R between the compressor stationary blade group and the rotor. Use a thickness gauge to measure the clearance at various locations of the compressor and record it in the engine record sheet.

[0041] Measure the turbine blade tip clearance, including the axial clearance and radial clearance between the turbine moving blades and the stationary blades. Use a thickness gauge to measure the clearances at various locations on the turbine and record them in the engine record sheet.

[0042] The advantages of the present invention are: the present invention can ensure the stability of the horizontal axis of the casing, eliminate the influence of elastic deformation, and obtain more accurate blade tip clearance values ​​of various parts. Using tooling to move the rotor can reduce the number of rotor hoisting times, is simple to operate, saves time and shortens the construction period. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the structure of the support in the horizontally adjustable support tooling of the casing;

[0044] Figure 2 It is a structural schematic diagram of the positioning plate in the thrust measurement fixture;

[0045] Figure 3 A schematic diagram of the structure of the afterburner for installing the adjustable horizontal support of the casing;

[0046] Figure 4 The schematic diagram of the structure of the combustion engine after installing the dial indicator;

[0047] Figure 5 It is a structural diagram of the dial indicator number and gap value;

[0048] Figure 6 This is a schematic diagram of the structure of the afterburner with the upper casing disassembled;

[0049] Figure 7 A schematic diagram of the structure for installing a rotor afterburner;

[0050] Figure 8a This is a schematic diagram of installing a dial indicator on the intake side. Figure 8b A is a partial enlarged view;

[0051] Figure 9a The schematic diagram of the thrust measurement fixture is shown below. Figure 9b It is a partial enlarged view B;

[0052] Fig.10 Schematic diagram of the structure of the afterburner with the thrust measurement fixture installed on the intake side;

[0053] Fig.11 It is a structural schematic diagram showing the rough position of dimension A;

[0054] Fig.12 It is a schematic diagram of the structure of the gap between the compressor blade tip and the stationary blade tip;

[0055] Fig.13 This is a schematic diagram of the structure of the clearance between the turbine blade tips and the stationary blade tips. DETAILED DESCRIPTION

[0056] The present invention is described in more detail below with reference to the accompanying drawings:

[0057] Combination Figure 1-13 The present invention provides a method for measuring and adjusting the tip clearance of a heavy-duty gas turbine. Through an improved measurement and adjustment method and matching tooling, the most accurate tip clearance of a heavy-duty gas turbine can be measured in a shorter time and with less operation. This measurement and adjustment method can ensure that the casing is not deformed during the measurement process, and a more accurate tip clearance can be obtained. The adjustment process does not require repeated hoisting of the rotor, and the rotor can be axially displaced by a jack. Due to the heavy weight of the heavy-duty gas turbine, a special jacking frame is manufactured to prevent the jacking force from damaging the rotor and the casing.

[0058] Casing horizontal adjustable support tooling: mainly composed of mechanical hydraulic jack (specification 10t), supports I-VII, supports, and adjustment bolts, see Figure 1 . Design an adjustable support according to the distance between the casing and the jack below, place the adjustable support and the mechanical hydraulic jack under the corresponding casing, use the jack to adjust the height of the adjustable support, tighten the casing, set the dial indicator to zero in the vertical direction, jack up the casing and record the dial indicator reading. In the steps where the casing load changes, such as disassembling the upper casing, installing the rotor, and installing the upper casing, the overall horizontal state of the casing can be confirmed by the dial indicator reading. It is used to control and detect the blade tip clearance measurement process, eliminate the elastic deformation of the casing due to its own weight and the upper installation load, and eliminate the influence of the bending of the axis of the lower casing caused by the disassembly of the upper casing.

[0059] Thrust measurement fixture: It consists of a left positioning plate, a right positioning plate, a gasket and a bracket, see Figure 2 Install a dial indicator on the casing, align it with the rotor end face, install an adjustment fixture at the force-bearing position of the rotor and casing, install a mechanical hydraulic jack between the casing and the rotor, apply pressure to move the rotor horizontally, and confirm the rotor movement by reading the dial indicator. Design according to the force-bearing surfaces of the casing and the rotor, fit the force-bearing surfaces, and evenly distribute the larger concentrated loads on the rotor and the casing to prevent the mechanical hydraulic jack from pressurizing and causing damage to the casing and the rotor top force surface.

[0060] ① In the early stage of assembly, a set of casing horizontal adjustable support fixtures and thrust bearing adjustment fixtures are customized to assist in measuring the blade tip clearance. When all the casings of the engine are connected as a whole and flipped to a horizontal state, the casing horizontal adjustable support fixtures are supported at the bottom of each casing to prevent the middle part of the engine from bending downward due to the heavy and long engine.

[0061] ② After fixing the horizontally placed receiver, separate the upper part of each receiver and slowly lift the rotor into the receiver.

[0062] ③ Adjust the rotor position, calculate the gasket thickness based on the result, replace the new gasket and install it.

[0063] ④ According to the design requirements of the secondary guide axial clearance A, confirm that the rotor position meets the requirements. The compressor casing tends to be closed, and the turbine casing tends to be expanded. If the A value is too large, the rotor position will be more biased towards the exhaust side, resulting in a larger compressor blade tip clearance and a smaller turbine blade tip clearance.

[0064] ⑤Fix the rotor and measure the axial and radial blade tip clearances required in the design drawing.

[0065] The steps of the present invention are specifically:

[0066] 1. Install the horizontal adjustable support tooling

[0067] 1. According to the rotor and casing size requirements of heavy-duty gas turbines, design casing horizontal adjustable support fixtures and thrust bearing adjustment fixtures, and install the casing horizontal adjustable support fixtures at the bottom of each casing. When the casing of the gas turbine is in a horizontal position as a whole, it is necessary to prevent the middle part of the component from bending downward. Set the jack 2 between the casing 1 and the fixture 3, and install it vertically on the foundation, see Figure 3 .

[0068] 2. The dial indicator 4 is set separately from the jack. The dial indicator is fixed on the adjustable horizontal support tooling of the casing. It is strictly forbidden to fix the dial indicator on the jack to prevent the influence of the pressure on the dial indicator reading due to the jack. Jacks are set at six locations under the casing, see Figure 4 . After manually tightening all jacks toward the receiver, set all dial indicator readings to "0".

[0069] 2. Adjust the receiver to ensure that the receiver is in a horizontal state

[0070] 1. Use a No. 2 jack to lift the flange joint between the turbine housing and the exhaust casing by about 0.06 to 0.10 mm, and record all dial indicator readings. Figure 5 . Make sure all jacks are under load (the jacks cannot be turned by hand).

[0071] 2. Use No. 3 jack to push the flange joint of the diffuser casing and the turbine casing to about 0.08-0.10mm, and record all dial indicator readings. Figure 5 . Make sure all jacks are under load (the jacks cannot be turned by hand).

[0072] 3. Use a No. 4 jack to lift the flange joint of the intermediate casing and the diffuser casing by about 0.10 to 0.12 mm, and record all dial indicator readings. Figure 5 . Make sure all jacks are under load (the jacks cannot be turned by hand).

[0073] 4. Use a No. 5 jack to lift the middle part of the middle casing by about 0.02 to 0.04 mm, and record all dial indicator readings. Figure 5 . Make sure all jacks are under load (the jacks cannot be turned by hand).

[0074] 5. Use a No. 6 jack to lift the rear side of the intake casing by about 0 to 0.01 mm, and record all dial indicator readings. Figure 5 . Make sure all jacks are under load (the jacks cannot be turned by hand).

[0075] 3. Disassemble the upper casing and install the rotor

[0076] 1. It is divided into the lower and upper exhaust casing, turbine casing, middle-expansion casing, inner cylinder, and intake casing, see Figure 6 . Confirm that the receiver is in a horizontal state by ensuring the values ​​of the dial indicators on the six jacks under the receiver.

[0077] 2. Lift the rotor and place it on the lower casing. Figure 7 . Read the dial indicator to confirm that the receiver is still in a completely horizontal state.

[0078] 3. The rotor position changes according to the thickness of the bearing gasket on the intake side. The rotor position close to the intake side will cause the compressor blade tip clearance to become smaller and the turbine blade tip clearance to become larger.

[0079] 4. Calculate the axial movement of the rotor

[0080] 1. Install process bushings in the upstream and downstream bearing seats with thicknesses of H1 and H2 respectively to prevent damage to the bearings during the process of pressing the rotor. Place a micrometer on the rotor intake side, with the dial facing the rotor end face and the horizontal position of the dial at the center plane of the casing, and return the reading to zero, as shown in Figure 8.

[0081] 2. Fix the thrust measuring fixture on the intake casing near the compressor wheel on the middle face of the intake casing, place the hydraulic jack between the fixture and the wheel (on the downstream side), one on each side, pressurize the hydraulic jack to 23MP, the purpose is to push the rotor completely to the intake side. Release the hydraulic jack and return the dial gauge to zero again. See Figure 9.

[0082] 3. Install the intake side bearing seat and place the hydraulic jack between the rotor flange surface and the end face of the No. 1 bearing seat (upstream side). Fig.10 . Pressurize the hydraulic jack to 23MPa, in order to push the rotor completely to the exhaust side. After the pressure reaches the requirement, gradually reduce the pressure, and after the dial gauge reading stabilizes, record the dial gauge reading at this time, which is the axial displacement of the rotor in the casing.

[0083] 4. Remove the hydraulic jack and put it back on the downstream side. Pressurize the hydraulic jack to 23MPa. After the pressure reaches the requirement, gradually reduce the pressure and record the reading of the dial gauge.

[0084] 5. Repeat the above steps at least 3 times until the value is stable. Calculate the average value M of the measured value of the rotor axial displacement based on the stable value.

[0085] 5. Install the gasket to determine the rotor position

[0086] 1. The position of the rotor relative to the casing is determined by determining the value of dimension A in the design drawing. Dimension A is the distance between the secondary partition and the casing. The approximate position is shown in Fig.11 The tip clearance of the rotor at this position is the tip clearance that meets the requirements of the drawing. The tip clearance will be affected by the inlet side or the exhaust side. Therefore, the rotor position must be determined to obtain accurate tip clearance.

[0087] 2. The thickness of the downstream process bushing is H2, and the thickness of the upstream process bushing is H1. Measure the actual value A of the axial clearance between the turbine 2nd stage diaphragm and the rotor. If the actual value of dimension A exceeds the specified range, calculate the thickness of the bushing according to the table, and adjust the bushing thickness to make dimension A meet the design requirements.

[0088] Table 1 Measurement value code

[0089]

[0090] Table 2 Formula for actual adjustment value

[0091]

[0092] 3. Disassemble the bearing seat, replace the process bushing with the calculated and ground formal bushing, install the bearing seat, and measure the actual measured value A of the axial clearance between the turbine 2nd stage diaphragm and the rotor. If it is unqualified, continue to adjust and replace the bushing thickness until it is qualified.

[0093] 6. Confirm the rotor position

[0094] 1. Install the bushing of qualified size, repeatedly press the rotor, confirm that the A size is between 9.40-9.70, and M is between 0.35-0.50. At this time, the rotor position is the measurement position required by the design drawing.

[0095] 7. Blade tip clearance measurement

[0096] 1. Compressor tip clearance measurement, including the stationary blade tip clearance S and the moving blade tip clearance R between the compressor stationary blade group and the rotor. Fig.12 . Use a thickness gauge to measure the gaps at various locations on the compressor and record them in the engine record sheet.

[0097] 2. Measurement of turbine blade tip clearance, including axial clearance and radial clearance between turbine moving blades and stationary blades. Fig.13 . Use a thickness gauge to measure the clearances at various locations on the turbine and record them in the engine record sheet.

[0098] This measurement method measures the most accurate tip clearance of heavy-duty gas turbines in a shorter time and with fewer operations. This measurement and adjustment method ensures that the casing is not deformed during the measurement process, and obtains a more accurate tip clearance. The adjustment process does not require repeated hoisting of the rotor, and the rotor can be axially displaced by a jack. Due to the heavy weight of heavy-duty gas turbines, a special jacking frame is manufactured to prevent the jacking force from damaging the rotor and casing. By measuring the clearance of various parts of the rotor while fully ensuring the measurement accuracy, a more accurate actual value can be obtained. It improves the impact of the inconvenience of hoisting the heavy-duty gas turbine rotor on the clearance measurement and adjustment, greatly reduces the hoisting process, and reduces the workload of personnel and project duration.

Claims

1. A method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine, characterized in that: The steps include: (1) Install the horizontal adjustable support tooling; (2) Adjust the force on the receiver so that everything is in a horizontal state; (3) Disassemble the upper casing and install the rotor; (4) Measure the axial movement of the rotor; (5) Install the gasket to determine the rotor position; (6) Confirm the rotor position; (7) Measure the blade tip clearance.

2. A heavy-duty gas turbine blade tip clearance measurement and adjustment method according to claim 1, characterized in that: The specific process of step (1) is as follows: A. Install the horizontal adjustable support fixtures of the receiver at the bottom of each receiver, set a jack between the receiver and the fixture, and install it vertically on the foundation; B. Fix the dial indicator on the adjustable horizontal support fixture of the receiver, set jacks at six locations under the receiver, tighten all jacks toward the receiver, and set all dial indicator readings to 0.

3. The method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine according to claim 1 is characterized in that: The specific process of step (2) is as follows: a. Use a No. 2 jack to lift the flange joint between the turbine housing and the exhaust casing by 0.06 to 0.10 mm, and record all dial indicator readings; b. Use No. 3 jack to push the flange joint between the diffuser casing and the turbine casing to 0.08-0.10mm, and record all dial indicator readings; c. Use a No. 4 jack to lift the flange joint of the intermediate casing and the diffuser casing by 0.10 to 0.12 mm, and record all dial indicator readings; d. Use a No. 5 jack to lift the middle part of the middle casing by 0.02 to 0.04 mm and record all dial indicator readings; e. Use a No. 6 jack to lift the rear side of the intake casing by 0 to 0.01 mm and record all dial indicator readings.

4. The method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine according to claim 1 is characterized by: The specific process of step (3) is as follows: I. Separate the upper exhaust casing, turbine casing, mid-expansion casing, inner barrel, and intake casing, and confirm that the casing is in a horizontal state by ensuring the values ​​of the dial indicators on the six jacks below the casing; II. Lift the rotor and place it on the lower casing. Read the dial indicator value to confirm that the casing is still in a completely horizontal state. III. The rotor position changes according to the thickness of the intake side bearing gasket.

5. The method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine according to claim 1 is characterized in that: The specific process of step (4) is as follows: i. Install process bushings in the upstream and downstream bearing seats, with thicknesses of H1 and H2 respectively, to prevent damage to the bearings during the process of pressing the rotor; place a micrometer on the rotor intake side, with the dial facing the rotor end face, the horizontal position of the dial at the middle dividing surface of the casing, and the reading is zero; ii. Fix the thrust measuring fixture on the intake casing at the position close to the compressor wheel on the middle plane of the intake casing, place the hydraulic jack between the fixture and the wheel, one on each side, pressurize the hydraulic jack, and push the rotor completely to the intake side; release the hydraulic jack and return the dial gauge to zero again; iii. Install the intake side bearing seat, place the hydraulic jack between the rotor flange surface and the end face of the No. 1 bearing seat (, pressurize the hydraulic jack, and push the rotor completely to the exhaust side. After the pressure reaches the requirement, gradually reduce the pressure. After the dial gauge reading stabilizes, record the dial gauge reading at this time. The reading is the axial displacement of the rotor in the casing; iv. Remove the hydraulic jack, put it back to the downstream side, pressurize the hydraulic jack, and gradually reduce the pressure after the pressure reaches the requirement, and record the reading of the dial gauge at this time; v. Repeat the above steps at least 3 times until the value is stable, and calculate the average value M of the measured value of the rotor axial displacement based on the stable value.

6. The method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine according to claim 1 is characterized by: The specific process of step (5) is as follows: ① Dimension A is the distance between the secondary partition and the casing. The position of the rotor relative to the casing is determined by determining the value of dimension A; ② The thickness of the process bushing on the downstream side is H2, and the thickness of the process bushing on the upstream side is H1. Measure the actual value A of the axial clearance between the turbine 2nd stage diaphragm and the rotor; if the actual value of dimension A exceeds the specified range, calculate the thickness of the bushing according to the table, and adjust the bushing thickness to make dimension A meet the design requirements; ③ Disassemble the bearing seat, replace the process bushing with the calculated and ground formal bushing, install the bearing seat, and measure the actual value A of the axial clearance between the turbine 2nd stage partition and the rotor. If it is unqualified, continue to adjust and replace the bushing thickness until it is qualified.

7. The method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine according to claim 1 is characterized by: The specific process of step (6) is as follows: install the bushing, repeatedly press the rotor, confirm that the A size is between 9.40-9.70, and M is between 0.35-0.

50. At this time, the rotor position is the measurement position that meets the requirements.

8. The method for measuring and adjusting the blade tip clearance of a heavy-duty gas turbine according to claim 1 is characterized by: The specific process of step (7) is as follows: Measure the compressor blade tip clearance, including the stationary blade tip clearance S and the moving blade tip clearance R between the compressor stationary blade group and the rotor. Use a thickness gauge to measure the clearance at various locations of the compressor and record it in the engine record sheet. Measure the turbine blade tip clearance, including the axial clearance and radial clearance between the turbine moving blades and the stationary blades. Use a thickness gauge to measure the clearances at various locations on the turbine and record them in the engine record sheet.

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