A method for measuring the sealing clearance of a rotor in a closed space

Abstract

The present invention discloses a method for measuring the sealing gap of a rotor in a closed space, mainly solving the technical problem that the measurement result of the sealing gap of the rotor in the closed space in the prior art is inaccurate. It includes measuring the diameter of the part of the rotor that cooperates with the stator sealing piece; measuring the inner diameter of the stator sealing piece; calculating the average gap along the radial direction between the rotor and the stator sealing piece; installing a tooling shaft, adjusting the axis position of the tooling shaft for coaxial measurement instead of the rotor; measuring the radial spacing between four positions on the outer peripheral surface of the tooling shaft and the corresponding stator sealing pieces respectively; calculating the radial eccentricity between the tooling shaft and the stator sealing piece at the first position and the second position and the radial eccentricity at the third position and the fourth position; converting the sealing gap value of the rotor; and determining whether the sealing gap value is within the designed sealing gap tolerance range.

Description

Technical Field

[0001] The present invention relates to a method for measuring a sealing gap, and more particularly to a method for measuring the sealing gap of a rotor in a closed space. Background Art

[0002] In compressors and exhaust gas expanders, in order to meet the performance requirements of the unit, a sealing member is often provided between the rotor and the stator. To ensure that there is no rubbing and collision between the rotor and the sealing member during rotation and to meet the sealing requirements, certain requirements are imposed on the gap between the stator sealing member and the rotor. Therefore, during the installation process, in order to ensure that the sealing gap of the rotor meets the design requirements, it is necessary to measure the sealing gap of the rotor to detect whether it meets the technical requirements.

[0003] Due to the structural limitations of the rotor, after the rotor is installed, the measurement part of the sealing gap of the rotor is in a closed space formed by the rotor and the stator, and it is impossible to directly measure it manually with measuring instruments. In the prior art, methods such as pressing lead wires are usually used to measure the gap. However, due to the small installation gap and the collision of the lead wires during the installation process, the measurement result of the sealing gap of the rotor is inaccurate. Summary of the Invention

[0004] The object of the present invention is to solve the technical problem that the measurement result of the sealing gap of the rotor in a closed space in the prior art is inaccurate, and to provide a method for measuring the sealing gap of the rotor in a closed space.

[0005] A method for measuring the sealing gap of a rotor in a closed space is characterized in that it is specifically implemented according to the following steps:

[0006] Step 1: Measure the diameter d of the part of the rotor that cooperates with the stator sealing piece;

[0007] Measure the inner diameter D of the stator sealing piece;

[0008] Calculate the average gap e along the radial direction between the rotor and the stator sealing piece 平均 ;

[0009] e 平均 =(D - d) / 2;

[0010] Step 2: Install a tooling shaft and adjust the axis position of the tooling shaft for coaxial measurement instead of the rotor;

[0011] Step 3: Define that the outer circumferential surface of the tooling shaft has a first position, a second position, a third position, and a fourth position. The radial distance between the first position and the second position and the radial distance between the third position and the fourth position are both equal to the diameter of the tooling shaft, and the radial connection line between the first position and the second position is perpendicular to the radial connection line between the third position and the fourth position;

[0012] Measure the radial distances between the first position, the second position, the third position, and the fourth position and the corresponding stator sealing plates, denoted as f1, f2, f3, and f4 respectively;

[0013] Step 4: Calculate the radial eccentric distances fa between the tooling shaft and the stator sealing plate at the first position and the second position, and fb between the tooling shaft and the stator sealing plate at the third position and the fourth position;

[0014] Step 5: Convert the sealing clearance values of the rotor;

[0015] Define that the outer circumferential surface of the rotor has a fifth position, a sixth position, a seventh position, and an eighth position, where the fifth position corresponds to the first position, the sixth position corresponds to the second position, the seventh position corresponds to the third position, and the eighth position corresponds to the fourth position;

[0016] The sealing clearance value e5 at the fifth position: e5 = e 平均 + fa;

[0017] The sealing clearance value e6 at the sixth position: e6 = e 平均 - fa;

[0018] The sealing clearance value e7 at the seventh position: e7 = e 平均 + fb;

[0019] The sealing clearance value e8 at the eighth position: e8 = e 平均 - fb;

[0020] Step 6: Determine whether e5, e6, e7, and e8 are all within the designed sealing clearance tolerance range. If so, the measurement is completed; if not, return to Step 2 until e5, e6, e7, and e8 are all within the designed sealing clearance tolerance range.

[0021] Further, in Step 4, the eccentric distances fa and fb satisfy the following formula:

[0022] fa = (f1 - f2) / 2, fb = (f3 - f4) / 2.

[0023] Further, in Step 2, determine the sealing clearance values at the first position, the second position, the third position, and the fourth position on the tooling shaft according to the measured coaxiality deviation between the tooling shaft and the stator sealing plate (the tooling shaft and the rotor are supported together, that is, the coaxiality of the tooling shaft and the rotor with the stator sealing plate is the same).

[0024] Further, the coaxiality between the tooling shaft and the stator sealing plate ≤ 0.05 mm; if the coaxiality between the tooling shaft 3 and the stator sealing plate 2 is greater than 0.05 mm, then adjust the position of the support for the tooling shaft 3.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] The present invention uses a tooling shaft to coaxially replace the rotor. By measuring the gap between the tooling shaft and the stator sealing piece, measuring the eccentricity of the tooling shaft, and then combining with the measured average gap between the rotor and the stator sealing piece, the sealing gap value during the actual installation of the rotor is obtained, realizing the indirect measurement of the gap between the stator seal and the rotor, solving the problem that the existing equipment cannot measure the sealing gap when directly installing the rotor, and the measurement method is simple and accurate. Description of the Drawings

[0027] Figure 1 is a schematic axial structure diagram of the tooling shaft and the stator sealing piece;

[0028] Figure 2 is a schematic radial structure diagram of the tooling shaft and the stator sealing piece;

[0029] Figure 3 is a schematic structure diagram of the rotor and the stator sealing piece.

[0030] In the figure, 1 - rotor, 2 - stator sealing piece, 3 - tooling shaft. Detailed Embodiment

[0031] The present invention will be described in detail below in conjunction with the drawings and specific embodiments.

[0032] In the description of the present invention, it should be noted that the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0033] Due to the structural characteristics of the rotor 1 itself, when the rotor 1 is installed on the stator, a relatively closed sealing space will be formed at the mating part of the rotor 1 and the stator sealing piece 2. Therefore, in order to facilitate the measurement of the gap between the rotor 1 and the stator sealing piece 2, the present invention uses a stepped cylindrical tooling shaft 3 to coaxially replace the rotor 1 for measurement.

[0034] A method for measuring the sealing gap of a rotor in a closed space according to the present invention is specifically implemented according to the following steps:

[0035] Step 1, measure the diameter d of the part of the rotor 1 that mates with the stator sealing piece 2; measure the inner diameter D of the opposite stator sealing piece 2; the measurement positions of D and d are as Figure 3 shown;

[0036] Calculate the average radial gap e between the rotor 1 and the stator sealing piece 2 平均 ;

[0037] e 平均 =(D - d) / 2;

[0038] Step 2: Install the tooling shaft 3. The structure and installation position of the tooling shaft 3 are as Figure 1 shown. Determine the seal clearance values at the first position, second position, third position, and fourth position on the tooling shaft 3 according to the coaxiality deviation between the measured tooling shaft 3 and the stator sealing piece 2. (The tooling shaft 3 and the rotor 1 are supported together, that is, the coaxiality between the tooling shaft 3 and the stator sealing piece 2 is equal to the coaxiality between the rotor 1 and the stator sealing piece 2), and use it to measure coaxially instead of the rotor 1. The coaxiality between the tooling shaft 3 and the stator sealing piece 2 ≤ 0.05 mm. If the coaxiality between the tooling shaft 3 and the stator sealing piece 2 is greater than 0.05 mm, then adjust the position of the support for the tooling shaft 3.

[0039] Step 3: Define that the outer circumferential surface of the tooling shaft 3 has a first position, a second position, a third position, and a fourth position. The radial distances between the first position and the second position and between the third position and the fourth position are both equal to the diameter of the tooling shaft 3, and the radial connection line between the first position and the second position is perpendicular to the radial connection line between the third position and the fourth position. In this embodiment, taking Figure 2 the perspective shown as a reference, the first position, the second position, the third position, and the fourth position are respectively the upper side position, the lower side position, the left side position, and the right side position of the tooling shaft 3 along the radial direction; in other embodiments of the present invention, the measurement positions can also be set to six, eight, ten, etc., and can be selected according to specific measurement accuracy requirements. Considering the complexity of calculation and relatively good calculation accuracy, four measurement positions are preferably selected in this embodiment.

[0040] Measure the radial distance between the first position and the corresponding (i.e., the smallest spacing) stator sealing piece 2, and record it as f1, measure the radial distance between the second position and the corresponding stator sealing piece 2, and record it as f2, measure the radial distance between the third position and the corresponding stator sealing piece 2, and record it as f3, measure the radial distances between the fourth position and the corresponding stator sealing piece 2 respectively, and record it as f4;

[0041] Step 4: Calculate the eccentricity fa in the radial connection line direction between the first position and the second position of the tooling shaft 3 and the stator sealing piece 2 and the eccentricity fb in the radial connection line direction between the third position and the fourth position.

[0042] fa = (f1 - f2) / 2, fb = (f3 - f4) / 2;

[0043] Step 5: Conversion of the seal clearance value on the outer circumferential surface of the rotor 1;

[0044] It is defined that the outer circumferential surface of the rotor 1 has a fifth position, a sixth position, a seventh position and an eighth position. Since the rotor 1 and the tooling shaft 3 are on the same axis and there is only a difference in diameter between them, in this embodiment, the fifth position corresponds to the first position, the sixth position corresponds to the second position, the seventh position corresponds to the third position, and the eighth position corresponds to the fourth position. That is, the fifth position is on the radial extension line of the first position, the sixth position is on the radial extension line of the second position, the seventh position is on the radial extension line of the third position, and the eighth position is on the radial extension line of the fourth position. In other embodiments of the present invention, the number of measurement positions on the outer circumferential surface of the rotor 1 is set to be the same as the number of measurement positions on the tooling shaft, such as six, eight or ten, etc., as long as the corresponding relationship is satisfied.

[0045] Sealing clearance value at the fifth position: e5 = e 平均 + fa;

[0046] Sealing clearance value at the sixth position: e6 = e 平均 - fa;

[0047] Sealing clearance value at the seventh position: e7 = e 平均 + fb;

[0048] Sealing clearance value at the eighth position: e8 = e 平均 - fb;

[0049] Step 6: Determine whether e5, e6, e7 and e8 are within the designed sealing clearance tolerance range. (The magnitudes of e5, e6, e7 and e8 can be judged, and only the maximum value and the minimum value need to be compared.) If so, the measurement is completed; if not, return to Step 2 until e5, e6, e7 and e8 are all within the designed sealing clearance tolerance range.

Claims

1. A method for measuring the sealing clearance of a rotor in a closed space, characterized in that, The implementation is carried out according to the following steps: Step 1: Measure the diameter d of the part of the rotor (1) that mates with the stator seal (2); Measure the inner diameter D of the stator seal (2); Calculate the average radial clearance e between the rotor (1) and the stator sealing piece (2) 平均 ; e 平均 = (D - d) / 2; Step 2: Install the tooling shaft (3), adjust the axial position of the tooling shaft (3) to coaxially replace the rotor (1) for measurement; Step 3: Define that the outer circumferential surface of the tooling shaft (3) has a first position, a second position, a third position, and a fourth position. The radial distances between the first position and the second position and between the third position and the fourth position are both equal to the diameter of the tooling shaft (3), and the radial connection line between the first position and the second position is perpendicular to the radial connection line between the third position and the fourth position; Measure the radial distances between the first position, the second position, the third position, and the fourth position and the corresponding stator seal (2) respectively, and denote them as f1, f2, f3, and f4; Step 4: Calculate the radial eccentricity fa between the tooling shaft (3) and the stator seal (2) at the first position and the second position and the radial eccentricity fb between the third position and the fourth position; Step 5: Convert the seal clearance value of the rotor (1); Define that the outer circumferential surface of the rotor (1) has a fifth position, a sixth position, a seventh position, and an eighth position, and the fifth position, the sixth position, the seventh position, and the eighth position correspond to the first position, the second position, the third position, and the fourth position respectively; Sealing clearance value e5 at the fifth position: e5 = e 平均 + fa; Sealing clearance value e6 at the sixth position: e6 = e 平均 - fa; Sealing clearance value e7 at the seventh position: e7 = e 平均 + fb; Sealing clearance value e8 at the eighth position: e8 = e 平均 -fb; Step 6: Judge whether e5, e6, e7, and e8 are all within the designed seal clearance tolerance range. If so, the measurement is completed; if not, return to Step 2 until e5, e6, e7, and e8 are all within the designed seal clearance tolerance range.

2. A method for measuring the seal clearance of a rotor in a closed space according to claim 1, wherein: In Step 4, the calculation formulas for the eccentricities fa and fb are as follows: fa = (f1 - f2) / 2, fb = (f3 - f4) / 2.

3. A method for measuring the seal clearance of a rotor in a closed space according to claim 2, wherein: In Step 2, determine the seal clearance values at the first position, the second position, the third position, and the fourth position on the tooling shaft (3) according to the coaxiality deviation between the tooling shaft (3) and the stator seal (2).

4. A method for measuring the seal clearance of a rotor in a closed space according to any one of claims 1-3, wherein: The coaxiality between the tooling shaft (3) and the stator seal (2) ≤ 0.05 mm.

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