A process for adjusting the clearance of a gas turbine rotor and turbine retaining ring

Abstract

The application provides a process for adjusting the rotor and the turbine retaining ring of a gas turbine, comprising the following steps: step one, calculating the axial actual size k of the axial adjusting gasket according to the axial actual size and the axial size on the drawing of each component of the gas turbine; step two, calculating the radial size of the trajectory point of the retaining ring according to the radial size of the reference point of the retaining ring, determining the axial size of the trajectory point and the angle between the straight line from the trajectory point to the corresponding point and the horizontal plane; step three, measuring the axial size of the to-be-measured point of the blade tip of the moving blade, and determining the axial size of the corresponding point according to the axial size of the to-be-measured point; step four, obtaining the radial size of the corresponding point according to the trigonometric formula; and step five, determining the radial size of the to-be-measured point according to the radial size of the corresponding point and the ideal gap value. The application calculates the position relationship between the moving blade and the retaining ring by the axial actual size of the axial adjusting gasket, so as to ensure that the position relationship meets the assembly requirements.

Description

Technical Field

[0001] This invention relates to the technical field of gas turbine assembly, and more particularly to the technical field of a process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine. Background Technology

[0002] The working principle of a gas turbine is that the compressor pressurizes the air, the gas mixture in the combustion chamber is pressurized, and finally the combustion gas is discharged into the turbine for expansion, which drives the rotor to rotate. Since the rotor is coaxial with the compressor, it can drive the compressor to work. Because the combustion gas in the turbine generally expands in the space formed by the moving blades and the corresponding stationary blades, the design of the clearance between the blade tip and the cylinder block, i.e. the flow clearance, has very high requirements and must meet the requirements of the drawings.

[0003] In gas turbine assembly, the blade tip height of the rotor is generally adjusted in two steps: rough grinding and fine grinding. This ensures that the flow clearance, i.e. the distance between the blade tip height and the inner wall of the corresponding retaining ring, meets the design requirements. Specifically, the rotor blade tip is rough ground on the main carriage, leaving a margin, and then placed into the cylinder (in the turbine retaining ring and compressor). After measuring the flow clearance, the rotor blade tip is supplied with the fine grinding dimensions. Finally, the rotor is removed from the cylinder and finely ground to the required dimensions.

[0004] However, this method requires a lot of manpower to check and test the flow clearance between the blade tip and the cylinder one by one, and it also requires lifting the rotor multiple times, which is time-consuming and labor-intensive. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine, in order to solve the problems of wasted manpower and wasted processes caused by repeated rotor lifting in the prior art.

[0006] To achieve the above and other related objectives, the present invention provides a process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine, comprising:

[0007] Step 1: Calculate the actual axial dimension k of the axial adjusting shim based on the actual axial dimensions of each component of the gas turbine and the axial dimensions on the drawing; then, obtain the deviation value Δk = kK of the axial adjusting shim from the determined axial dimension K on the drawing.

[0008] Step 2: Measure the deviation value δ of the radial dimension of the reference point of the turbine holder, determine the radial diameter L and axial dimension M of the trajectory point of the turbine holder, and the angle θ between the straight line from the trajectory point to the corresponding point and the horizontal plane.

[0009] Step 3: Measure the axial dimension n of the test point at the tip of the moving blade inside the turbine holding ring, and determine the axial dimension n of the corresponding point based on the axial dimension n of the test point.

[0010] Step 4: According to the trigonometric formula, the radial diameter p of the corresponding point is p = (L / 2 + δ / 2 + (Mn)*tanθ - △k*tanθ)*2;

[0011] Step 5: Determine the radial diameter s of the point to be measured based on the radial diameter p of the corresponding point and the ideal gap value R. s = (p / 2 - R / cosθ) * 2.

[0012] Step 6: According to the radial diameter s of the point to be measured, grind the multiple moving blades of the rotor once, and then hoist the rotor into the turbine holding ring in one step.

[0013] Preferably, the components of the gas turbine include the dimensions of the parts to be installed and the rotor dimensions; the difference between the sum of the deviations of the dimensions of the parts to be installed and the sum of the deviations of the rotor dimensions is equal to the deviation value Δk of the axial adjusting shim.

[0014] Preferably, the rotor dimensions need to be measured on a trolley.

[0015] Preferably, the axial dimension of the point to be measured is equal to the axial dimension of the corresponding point.

[0016] Preferably, the radial and axial dimensions of the retaining ring and cylinder components are measured after finishing.

[0017] Preferably, the moving blade is aligned with a flow channel surface of the turbine retaining ring, the flow channel surface including a first inclined surface, a second inclined surface and a plane; the first inclined surface turns from the trajectory point to the second inclined surface, and the second inclined surface turns from the reference point to the plane.

[0018] As described above, the process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine according to the present invention has the following beneficial effects:

[0019] This invention calculates the deviation values ​​of each component to obtain the corresponding deviation values ​​of the axial adjustment shims. Finally, based on the equation, it obtains the actual axial dimension and deviation value Δk of the axial adjustment shims. This ensures that the axial position of the blade tip and the inner wall of the turbine retaining ring are within the design range, and also improves the accuracy of subsequent radial diameter calculations for the points to be measured. This invention uses known ideal clearance values ​​and the calculated radial diameter of the corresponding points to calculate the diameter of the blade tip of the moving blade to be cut in one step, reducing the original multiple processing steps and the manpower and resources consumed, thus lowering time and labor costs. Attached Figure Description

[0020] Figure 1 The diagram shows the components of a gas turbine as an example of a process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine according to the present invention.

[0021] Figure 2 The diagram shows a geometrical representation of the radial dimensions of the turbine bearing and the moving blade at corresponding points, illustrating a process for adjusting the clearance between the rotor and turbine bearing of a gas turbine according to the present invention.

[0022] Figure 3 The diagram shows a geometrical schematic of the turbine retainer and the moving blades, used to calculate the radial dimensions of the points to be measured, in accordance with the present invention, a process for adjusting the gap between the rotor and turbine retainer of a gas turbine.

[0023] Figure 4 This diagram illustrates a geometrical representation of a process for adjusting the gap between the rotor and turbine retainer of a gas turbine according to the present invention, when a deviation occurs in the radial dimension of the turbine retainer.

[0024] Component designation explanation

[0025] 1. Compressor bearing housing

[0026] 2. Compressor holding ring

[0027] 3. First cylinder

[0028] 4 Second cylinder

[0029] 5. Belt groove

[0030] 61 journal opening

[0031] 62 shaft head

[0032] 63 First-level roulette

[0033] 7 Turbine holding ring

[0034] 8. Moving leaves Detailed Implementation

[0035] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0036] Please see Figures 1 to 4It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of the invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0037] like Figures 1 to 4 As shown, the present invention provides a process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine, comprising:

[0038] Step 1: Calculate the actual axial dimension k of the axial adjusting shim based on the actual axial dimensions of each component of the gas turbine and the axial dimensions on the drawing; then, based on the determined axial dimension K of the axial adjusting shim on the drawing, obtain the deviation value Δk = kK of the axial adjusting shim.

[0039] Step 2: Measure the deviation value δ of the radial diameter of the reference point of the turbine holding ring 7, determine the radial diameter L and axial dimension M of the trajectory point of the turbine holding ring 7, and the angle θ between the straight line from the trajectory point to the corresponding point and the horizontal plane.

[0040] Step 3: Measure the axial dimension n of the test point at the tip of the moving blade 8 inside the turbine holding ring 7, and determine the axial dimension n of the corresponding point from the axial dimension n of the test point.

[0041] Step 4: According to the trigonometric formula, the radial diameter p of the corresponding point is p = (L / 2 + δ / 2 + (Mn)*tanθ - △k*tanθ)*2;

[0042] Step 5: Determine the radial diameter s of the point to be measured based on the radial diameter p of the corresponding point and the ideal gap value R. s = (p / 2 - R / cosθ) * 2.

[0043] Step 6: According to the radial diameter s of the point to be measured, grind the multiple moving blades 8 of the rotor once, and then hoist the rotor into the turbine holding ring 7 in one step.

[0044] This invention calculates the deviation values ​​(difference between the actual axial dimension and the axial drawing dimension) of each component to obtain the corresponding deviation value of the axial adjustment shim. Finally, based on the equation, the actual axial dimension and deviation value Δk of the axial adjustment shim are obtained. This ensures that the axial position of the blade tip of the moving blade 8 and the inner wall of the turbine retaining ring 7 is within the design range, and also improves the accuracy of the subsequent calculation of the radial diameter s of the test point. This invention uses the known ideal clearance value R and the calculated radial diameter p of the corresponding point to calculate the diameter s of the blade tip of the moving blade 8 to be cut (i.e., the radial dimension of the test point) in one step, reducing multiple processing steps and the manpower and material resources consumed, thus lowering time and labor costs. Furthermore, this invention discloses the clearance between the turbine retaining ring 7 and the corresponding blade tip of the moving blade 8, but it can be applied to the clearance calculation method between the compressor retaining ring and the corresponding moving blade 8 according to actual needs, which will not be elaborated here.

[0045] Because there will be deviations between the drawing dimensions and the actual machining dimensions of most parts, when positioning the axial distance between the rotor blade 8 and the turbine retaining ring 7, it is necessary to consider the deviation values ​​of each component, and the position of the turbine retaining ring 7 needs to be adjusted using axial adjusting shims. Furthermore, because... Figure 1 Therefore, the deviation value Δk of the axial adjusting shim is equal to the sum of the dimensional deviations of the parts to be installed (axially) minus the sum of the dimensional deviations of the rotor (axially). Specifically, from Figure 1 It can be seen that the sum of the dimensional deviations of the parts to be installed is obtained by adding the deviations of the axial dimensions of the compressor bearing housing 1, compressor retaining ring 2, first cylinder block 3, second cylinder block 4, and belt groove 5. Similarly, the sum of the rotor dimensional deviations is obtained by adding the axial dimensions of the journal opening 61, the axial distance from the shaft head 62 to the turbine first stage disc 63, and the axial dimension of the turbine retaining ring 7. Specifically, the formula is as follows:

[0046] The sum of the dimensional deviations of the parts to be installed, Δ1, is: a-A+b-B+c-C+d-D+eE;

[0047] The sum of rotor dimensional deviations Δ2 = f - F + g - G + hH;

[0048] △k=kK=△1-△2=a-A+b-B+c-C+d-D+eE-(f-F+g-G+hH);

[0049] k=K+a-A+b-B+c-C+d-D+eE-(f-F+g-G+hH);

[0050] a is the actual axial dimension of compressor bearing housing 1, and A is the axial dimension of compressor bearing housing 1 as shown in the drawing; b is the actual axial dimension of compressor retaining ring 2, and B is the actual axial dimension of compressor retaining ring 2; c is the actual axial dimension of first cylinder 3, and C is the actual axial dimension of first cylinder 3; d is the actual axial dimension of second cylinder 4, and D is the axial dimension of second cylinder 4 as shown in the drawing; e is the actual axial dimension of belt groove 5, and E is the axial dimension of belt groove 5 as shown in the drawing; f is the actual axial dimension of turbine retaining ring 7, and F is the axial dimension of turbine retaining ring 7 as shown in the drawing; h is the actual axial dimension of shaft diameter opening 61, and H is the axial dimension of shaft diameter opening 61 as shown in the drawing; g is the axial distance from shaft head 62 to turbine first stage wheel 63, and G is the axial distance from shaft head 62 to turbine first stage wheel 63.

[0051] Because the rotor is very long, it needs to be placed on a large vehicle for measurement in order to improve the accuracy of the measurement.

[0052] Since the corresponding point is the point on the turbine retaining ring 7 corresponding to the point to be measured in the same axial dimension, such as Figure 2 As shown, the axial dimension of the point to be measured is equal to the axial dimension of the corresponding point.

[0053] like Figure 2 As shown, to obtain the radial diameter p of the corresponding point, it is necessary to first obtain the radial radius p / 2 of the corresponding point; as Figure 2 As shown, the radial radius of the corresponding point is equal to the radial radius of the trajectory point plus the radial radius from the corresponding point to the trajectory point, i.e., p / 2 = L / 2 + x.

[0054] like Figure 3 As shown, the moving blade 8 is aligned with a flow channel surface of the turbine holding ring 7. The flow channel surface includes a first annular cone surface, a second annular cone surface, and a cylindrical surface. The first annular cone surface turns from the trajectory point to the second annular cone surface, and the second annular cone surface turns from the reference point to the cylindrical surface.

[0055] like Figure 4 As shown, when the actual size of the reference point deviates, the same deviation will occur in the machining of the entire turbine holding ring 7, resulting in the deviation value of the trajectory point being consistent with the deviation value of the reference point; that is, the radial dimension change δ of the reference point is the radial dimension change of the trajectory point, so the actual radial radius of the trajectory point is L / 2+δ / 2.

[0056] Similarly, the deviation value △k of the axial adjustment shim will cause the axial position of the turbine holding ring 7 to change. The change in the axial position of the turbine holding ring 7 will change the radial radius of the trajectory point. The specific change is (kK)*tanθ, that is, p / 2=L / 2+δ / 2+x+(kK)*tanθ.

[0057] From the above formula, we can finally derive p=(L / 2+δ / 2+x+(kK)*tanθ)*2·····························(1)

[0058] Due to the combination of the trigonometric tangent formula Figure 2 As shown, x=(Mn)*tanθ······················(2)

[0059] Substituting equation (2) into equation (1), we get p=(M / 2+δ / 2+(Mn)*tanθ-(kK)*tanθ)*2······(3)

[0060] like Figure 3 As shown, the ideal gap value R between the moving blade 8 and the turbine holding ring 7 (the shortest distance, i.e., the perpendicular line drawn from the first annular cone surface to the point to be measured) can be used to determine the radial difference between the corresponding point and the point to be measured, y1 = R / cosθ.

[0061] The radial radius of the point to be measured is s / 2 = p / 2 - y1 = p / 2 - Rcosθ

[0062] We deduce that s = (p / 2 - R / cosθ) * 2

[0063] Finally, based on the estimated radial diameter s of the point to be measured, the tip of the moving blade 8 was machined, avoiding the effort and time wasted on repeated measurement and grinding.

[0064] In summary, by utilizing the measured axial dimensions of each component, this invention can determine the actual axial dimension of the axial adjustment shim, thereby ensuring that the relative axial position of the moving blade 8 and the turbine holding ring 7 meets the design requirements. Furthermore, by measuring the radial diameter L and axial dimension M of the track point of the turbine holding ring 7, and measuring the axial dimension n of the point to be measured, this invention can determine the radial diameter s of the point to be measured, thus enabling the adjustment of the tip height of all moving blades 8 of the rotor in one operation, avoiding the waste of manpower and resources caused by repeated grinding.

[0065] Therefore, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0066] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine, characterized in that, include: Step 1: Calculate the actual axial dimension k of the axial adjusting shim based on the actual axial dimensions of each component of the gas turbine and the dimensions shown on the axial drawing. Then, based on the determined axial dimension K of the axial adjusting shim on the axial drawing, obtain the deviation value △k = kK of the axial adjusting shim. Each component of the gas turbine includes the dimensions of the parts to be installed and the rotor dimensions. The difference between the sum of the deviations of the dimensions of the parts to be installed and the sum of the deviations of the rotor dimensions is equal to the deviation value △k of the axial adjusting shim. The sum of the deviations of the dimensions of the parts to be installed is △1 = a - A + b - B + c - C + d - D + eE, and the sum of the deviations of the rotor dimensions is △2 = f - F + g - G + hH. △k = kK = △1 - △2, where a is the compressor bearing housing. The actual axial dimensions are as follows: A is the axial dimension of the compressor bearing housing as shown in the drawing; b is the actual axial dimension of the compressor retainer ring as shown in the drawing; c is the actual axial dimension of the first cylinder as shown in the drawing; d is the actual axial dimension of the second cylinder as shown in the drawing; e is the actual axial dimension of the belt groove as shown in the drawing; f is the actual axial dimension of the turbine retainer ring as shown in the drawing; h is the actual axial dimension of the shaft diameter opening as shown in the drawing; g is the actual axial distance from the shaft head to the first stage turbine disc as shown in the drawing; G is the actual axial distance from the shaft head to the first stage turbine disc as shown in the drawing. Step 2: Measure the deviation δ between the actual radial diameter of the reference point of the turbine retainer and the radial diameter on the drawing, and determine the radial diameter L and axial dimension M of the trajectory point of the turbine retainer as shown on the drawing, as well as the angle θ between the straight line from the trajectory point to the corresponding point and the horizontal plane. Step 3: Measure the axial dimension of the point to be measured at the tip of the moving blade inside the turbine holding ring, and determine the axial dimension n of the corresponding point based on the axial dimension of the point to be measured; Step 4: According to the trigonometric formula, the radial diameter p of the corresponding point is p = (L / 2 + δ / 2 + (Mn) * tanθ - Δk * tanθ) * 2; Step 5: Determine the radial diameter s of the point to be measured based on the radial diameter p of the corresponding point and the ideal gap value R = (p / 2 - R / cosθ) * 2; Step 6: According to the radial diameter s of the point to be measured, grind the multiple moving blades of the rotor once, and then hoist the rotor into the turbine holding ring in one step.

2. The process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine according to claim 1, characterized in that: The rotor dimensions are the axial dimensions of the assembly, and the rotor axial dimensions need to be measured on a horizontal lathe.

3. The process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine according to claim 1, characterized in that: The radial and axial dimensions of the retaining ring and cylinder components are measured after finishing.

4. The process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine according to claim 1, characterized in that: The axial dimension of the point to be measured is equal to the axial dimension of the corresponding point.

5. The process for adjusting the gap between the rotor and turbine retaining ring of a gas turbine according to claim 1, characterized in that: The moving blade is aligned with the flow channel surface of the turbine holding ring, the flow channel surface including a first inclined surface, a second inclined surface and a plane; the first inclined surface turns from the trajectory point to the second inclined surface, and the second inclined surface turns from the reference point to the plane.

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