A device for quickly detecting the steam seal gap of a steam turbine and a method of use

Abstract

The application relates to a device for rapidly detecting a steam seal gap of a steam turbine and a use method, relates to the technical field of steam seal gap detection, and is suitable for measuring a radial gap; the steam seal structure of the steam turbine comprises a steam seal tooth and a rotor; the device comprises an adhesive layer, a strain layer, a coating layer and a back adhesive paper; the adhesive layer comprises a back surface and a front surface; the back surface is used for adhering the coating layer and is glued to the surface of the steam seal tooth through the coating layer; the front surface is in contact with the surface of the rotor; the strain layer is wrapped between the back surface of the adhesive layer and the coating layer; the coating layer is located between the adhesive layer and the back adhesive paper; the application aims at the steam seal gap detection problem of the steam turbine, realizes the purposes of reducing the measurement error and quantitatively detecting the steam seal gap of each position of the steam seal structure through the adhesive layer, the strain layer, the coating layer and the back adhesive paper, and has the advantages of simple structure, safety and reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steam seal gap detection, in particular to a device for rapidly detecting steam turbine steam seal gap and a use method thereof. BACKGROUND

[0002] The steam seal of a steam turbine is a structure arranged between the moving and static parts of the steam turbine to reduce or prevent steam leakage and air leakage from the vacuum side. In order to avoid collision between the moving and static parts of the steam turbine, a proper gap must be left, but the existence of the gap will inevitably cause steam leakage and reduce the efficiency of the steam turbine. In order to solve this contradiction, a sealing device, i.e. the steam seal, is installed at the gap between the moving and static parts of the steam turbine.

[0003] The radial gap is one of the gaps generated by the steam seal structure. The currently commonly used method for detecting the radial gap is to use medical adhesive tape. However, the use of medical adhesive tape has the following problems:

[0004] 1. The use of medical adhesive tape can only determine the range of the size of the gap and qualitatively determine the position of the gap, but cannot quantitatively determine the size of the gap.

[0005] 2. The medical adhesive tape is a whole device, and the production of a corresponding strip-shaped structure can easily cause uneven thickness, thereby causing measurement errors and affecting the equipment maintenance period.

[0006] 3. The medical adhesive tape has poor adhesion to metal, and the use of medical adhesive tape can easily cause hollowing, overlapping or lifting, which can easily cause measurement errors. SUMMARY

[0007] The purpose of the present application is to provide a device for rapidly detecting steam turbine steam seal gap and a use method thereof, which aims to reduce measurement errors and enable repeated use for detecting steam seal gap and quantitatively detecting the size of the gap.

[0008] The purpose of the present application is achieved by the following technical solutions:

[0009] A device for rapidly detecting steam turbine steam seal gap is used for detecting the radial gap measurement of a 125MW, 200MW, 300MW, 600MW and 1000MW unit type steam turbine. The steam turbine steam seal structure includes a steam seal tooth and a rotor. The device includes an adhesive layer, a strain layer, a coating layer and a back adhesive paper. The adhesive layer includes a back surface and a front surface. The back surface is used to adhere to the coating layer and is glued to the surface of the steam seal tooth through the coating layer. The front surface is in contact with the surface of the rotor. The strain layer is wrapped between the back surface of the adhesive layer and the coating layer. The coating layer is located between the adhesive layer and the back adhesive paper.

[0010] Further, the strain layer comprises a negative surface and a positive surface, the positive surface is attached to the back surface, and the negative surface is attached to the coating layer; the center of the strain layer is collinear with the center of the adhesive layer, and the strain layer is coated by the coating layer around.

[0011] Further, a display end is further included, a signal generator is arranged in the coating layer, the signal generator is electrically connected with the strain gauge, and the signal generator is wirelessly connected with the display end.

[0012] Further, the back adhesive paper is PP back adhesive paper.

[0013] Further, the adhesive layer material is adhesive tape or rubber.

[0014] Further, the coating layer adopts any one of sodium dodecyl benzene sulfonate, sodium citrate, 2-mercaptobenzothiazole, Na3PO4, Ce(NO3)3 and NaVO3.

[0015] Further, the device shape comprises side adhesive edges located on two sides and end surface adhesive edges located between the two side adhesive edges; the side adhesive edges and the end surface adhesive edges are formed by integrated bending.

[0016] A device for quickly detecting a steam seal gap of a steam turbine is used for a method for detecting a steam seal gap, and comprises the following steps:

[0017] S1: cleaning stains and oil stains on the steam seal structure;

[0018] S2: after S1, uniformly applying red lead powder on the surface of the rotor and hoisting the rotor back to the working position of the rotor;

[0019] S3: after S2, tearing off the back adhesive paper of the device, adhering the device to the steam seal tooth, and pressing tightly;

[0020] S4: after S3, hoisting the steam seal tooth with the detection device back to the sealing structure, wirelessly connecting the signal generator with the display end stably, keeping the working position of the rotor unchanged, and rotating for 3-4 rounds;

[0021] S5: after S4, hoisting out the rotor, checking the friction marks of the adhesive layer front surface of the device on the red lead powder, preliminarily judging the size and corresponding position of the steam seal gap of the steam turbine steam seal structure, and quantitatively judging the size of the steam seal gap of the corresponding position in combination with the signal transmitted to the display end by the strain layer.

[0022] The present application has the following advantages:

[0023] 1. The back adhesive paper can effectively protect the coating layer, avoid the coating layer from being oxidized due to contact with air and contact with dust in the air, and thus ensure the service life of the device.

[0024] 2. The coating is used to ensure that the device is in use, the distance between each position of the adhesive layer and the surface of the seal tooth is equal (i.e. the thickness is uniform) and the mechanical deformation of the strain layer is restored, thereby reducing the measurement error and increasing the accuracy of the measurement;

[0025] 3. The coating is used to ensure that the adhesive layer can be stably bonded to the metal surface, and defects such as hollowing, overlapping and warping do not occur, thereby ensuring that the measurement gap is stable and accurate.

[0026] 4. When measuring the gap, the mechanical deformation of the strain layer can change the resistance value, thereby quantitatively determining the size of the gap. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor

[0028] Figure 1 is a structural schematic diagram of the present application;

[0029] Figure 2 is a first shape schematic diagram of the present device;

[0030] Figure 3 is a second shape schematic diagram of the present device;

[0031] Figure 4 is a third shape schematic diagram of the present device;

[0032] In the figure: 1 - adhesive layer; 2 - coating; 3 - adhesive paper; 4 - side adhesive edge; 5 - end face adhesive edge; 6 - strain layer; 7 - display end; 8 - signal generator. DETAILED DESCRIPTION

[0033] The present application will be further described below in conjunction with the drawings, but the scope of protection of the present application is not limited to the following description.

[0034] As shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 , a device for quickly detecting the steam seal gap of a steam turbine, which is used for detecting the radial gap measurement of a steam turbine of 125MW, 200MW, 300MW, 600MW and 1000MW unit type, the steam seal structure of the steam turbine includes a seal tooth and a rotor, a device for quickly detecting the steam seal gap of a steam turbine, which includes an adhesive layer 1, a strain layer 6, a coating 2 and an adhesive paper 3, wherein:

[0035] The adhesive layer 1 includes a back surface and a front surface, the back surface is used to adhere the coating 2 and is glued to the surface of the steam seal tooth through the coating 2, and the front surface is in contact with the surface of the rotor; the strain layer 6 is wrapped between the back surface of the adhesive layer 1 and the coating 2; and the coating 2 is located between the adhesive layer 1 and the back adhesive paper 3.

[0036] In the embodiment, the strain layer 6 includes a negative surface and a positive surface, the positive surface is attached to the back surface, and the negative surface is attached to the coating 2; the center of the strain layer 6 is collinear with the center of the adhesive layer 1, and the strain layer 6 is covered by the coating 2 around, which can protect the strain layer 6 from being damaged due to friction.

[0037] In the embodiment, a display end 7 is further included, a signal generator (8) is arranged in the coating, the signal generator 8 is electrically connected with the strain layer 6, and the signal generator 8 is wirelessly connected with the display end 7; when measuring the steam seal gap of the whole circle steam seal structure, the mechanical deformation of the strain layer 6 changes the resistance value due to different gaps, so that the mechanical deformation value of the strain layer 6 is quantitatively reflected to the display end 7 through the signal generator 8; the total thickness of the device is reduced by the strain value, so that the steam seal gap is obtained; and the steam seal gap is quantitatively obtained. In order to facilitate the adhesion of the coating 2 to the metal surface, the back adhesive paper 3 is preferably selected from PP back adhesive paper 3, which can effectively protect the coating 2, avoid the oxidation of the coating 2 due to contact with air and contact with dust in the air, and thus ensure the service life of the device.

[0038] In the embodiment, the material of the adhesive layer 1 can be selected from one or more of adhesive tape or rubber.

[0039] In order to ensure that the distances between the positions of the adhesive layer 1 and the surface of the steam seal tooth are equal, the coating 2 needs to be uniformly covered on the back surface of the adhesive layer 1, and the coating 2 is any one of sodium dodecyl benzene sulfonate, sodium citrate, 2-mercaptobenzothiazole, Na3PO4, Ce(NO3)3 and NaVO3, because the coating 2 has self-releasing, migration and synergistic repair mechanism, and can restore the thickness itself, so as to avoid the uneven force during pressing with hands, which causes the distances between the positions of the adhesive layer 1 and the surface of the steam seal tooth to be not equal; during the measurement, the local position of the strain layer 6 will produce mechanical deformation, the coating 2 is arranged on the negative surface of the strain layer 6, and through the self-releasing, migration and synergistic repair mechanism of the coating 2, the mechanical deformation of the strain layer 6 can be restored, so as to ensure that the display end 7 displays the periodic diagram in the shape of pulse.

[0040] In order to protect the signal generator 8 from being damaged by the rotation of the rotor, in the embodiment, the signal generator 8 is located on the negative side of the strain layer 6. Since the coating layer 2 has self-releasing, migration and synergistic repair mechanisms, it has a certain collision buffering capacity, and the signal generator 8 is arranged in the coating layer to protect the signal generator 8; the signal generator 8 is self-powered. According to different steam seal structures, the device is manufactured into a first shape:

[0041] As shown in Figure 2 , the device is integrally bent into a side adhesive edge 4 and an end face adhesive edge 5, the end face adhesive edge 5 is bent into 6 grooves for bonding the steam seal teeth, so that each steam seal tooth in the steam seal structure can be bonded; the side adhesive edge 4 is bonded with the two side faces of the steam seal structure.

[0042] According to different steam seal structures, the device is manufactured into a second shape:

[0043] As shown in Figure 3 , the device is integrally bent into a side adhesive edge 4 and an end face adhesive edge 5, the end face adhesive edge 5 is bent into 2 grooves for bonding the steam seal teeth, so that each steam seal tooth in the steam seal structure can be bonded; the side adhesive edge 4 is bonded with the two side faces of the steam seal structure.

[0044] According to different steam seal structures, the device is manufactured into a third shape:

[0045] As shown in Figure 4 , the device is integrally bent into a side adhesive edge 4 and an end face adhesive edge 5, the end face adhesive edge 5 is bent into 2 grooves for bonding the steam seal teeth, so that each steam seal tooth in the steam seal structure can be bonded; the side adhesive edge 4 is bonded with the two side faces of the steam seal structure.

[0046] A device for quickly detecting the steam seal gap of a steam turbine is used for the method for detecting the steam seal gap, comprising the following steps:

[0047] S1: cleaning the dirt and oil stains on the steam seal structure;

[0048] S2: after performing S1, evenly applying red lead powder on the surface of the rotor and hoisting the rotor back to the working position of the rotor;

[0049] S3: after performing S2, tearing off the adhesive paper 3 of the device, bonding the device on the steam seal teeth, and pressing them tightly;

[0050] S4: after performing S3, hoisting the steam seal teeth with the detection device back to the sealing structure, stably connecting the detection signal generator 8 with the display end 7, in order to ensure stable wireless connection, the distance between the signal generator 8 and the display end is preferably not more than 5m; keeping the working position of the rotor unchanged, rotating 4 circles; in the embodiment, the display end 7 will display 4 same periods.

[0051] S5: After S4, the rotor is lifted out, the friction marks of the red powder on the front of the adhesive layer 1 of the device are observed, the size of the steam seal gap at the steam seal structure of the steam turbine and the corresponding position are preliminarily judged, and the size of the steam seal gap at the corresponding position can be quantitatively judged by combining the signals transmitted to the display end 7 by the signal generator 8 through the strain layer 6.

[0052] It should be noted that in the present embodiment, when the gap value displayed by the display end 7 at each position can be determined to correspond to the corresponding position, red powder is not used, and when red powder is not used, the device can be reused.

[0053] In the embodiment of the present application, when the device for quickly detecting the steam seal gap of the steam turbine is used to detect steam seal structures with different steam seal gaps, it should be noted that the thickness of the adhesive layer 1 can be changed according to actual needs, thereby changing the overall thickness of the device, and thereby changing the friction marks of the red powder on the front of the adhesive layer 1; in the present embodiment, when the device with a total thickness of 0.75 mm is used to detect steam seal structures with different gaps, the display results of the adhesive layer 1 and the display end 7 are as follows:

[0054] When the steam seal gap is 0.90 mm, there is no red color on the adhesive layer 1; the strain layer 6 has no strain, and the display end 7 has no pulse display;

[0055] When the steam seal gap is 0.85 mm, there is no red color on the adhesive layer 1; the strain layer 6 has no strain, and the display end 7 has no pulse display;

[0056] When the steam seal gap is 0.80 mm, there is no red color on the adhesive layer 1; the strain layer 6 has no strain, and the display end 7 has no pulse display;

[0057] When the steam seal gap is 0.75 mm, a red color is just visible on the adhesive layer 1; the display end 7 has a pulse display value of the strain value;

[0058] When the steam seal gap is 0.70 mm, the red color on the adhesive layer 1 is relatively deep; the display end 7 has a pulse display value of the strain value;

[0059] When the steam seal gap is 0.65 mm, the red color on the adhesive layer 1 is relatively deep, and part of it is purple; the display end 7 has a pulse display value of the strain value;

[0060] When the steam seal gap is 0.60 mm, a small amount of red color can be seen on the adhesive layer 1, and a large amount of purple color appears; the display end 7 has a pulse display value of the strain value;

[0061] When the steam seal gap is 0.55 mm, a small amount of black color can be seen on the adhesive layer 1; the display end 7 has a pulse display value of the strain value;

[0062] When the steam seal gap is 0.50mm, a small amount of purple and a large amount of black can be seen on the adhesive layer 1; the pulse display value of the display end 7 is the strain value;

[0063] When the steam seal gap is 0.45mm, a large amount of black and basically no purple can be seen on the adhesive layer 1; the pulse display value of the display end 7 is the strain value;

[0064] When the steam seal gap is 0.40mm, the black on the adhesive layer 1 is deepened and no other color can be seen; the pulse display value of the display end 7 is the strain value;

[0065] The above data shows that when the steam seal gap is detected by the device, the size and position of the steam seal gap can be directly and clearly observed, and the data of the strain gauge 6 on the display end 7 can be reflected, and the combination of the two can quantitatively and clearly determine the size of the gap at the corresponding position.

Claims

1. A device for fast detection of turbine gland seal clearance for measuring radial clearance of turbine of 125 MW, 200 MW, 300 MW, 600 MW and 1000 MW unit type, the structure of the turbine gland seal comprising of gland seal teeth and rotor, characterized in that: It comprises an adhesive layer (1), a strain layer (6), a coating layer (2) and a back adhesive paper (3), wherein: The adhesive layer (1) comprises a back surface and a front surface, the back surface is used for adhering the coating layer (2) and is glued to the surface of the steam seal tooth through the coating layer (2), and the front surface is in contact with the surface of the rotor; the strain layer (6) is wrapped between the back surface of the adhesive layer (1) and the coating layer (2); the coating layer (2) is located between the adhesive layer (1) and the back adhesive paper (3); and a display end (7) is further included, the coating layer is provided with a signal generator (8), the signal generator (8) is electrically connected with the strain layer (6), the signal generator (8) is wirelessly connected with the display end (7), and the coating layer (2) adopts any one of sodium dodecyl benzene sulfonate, sodium citrate, 2-mercaptobenzothiazole, Na3PO4, Ce(NO3)3 and NaVO3. The strain layer (6) comprises a negative surface and a positive surface, the positive surface is attached to the back surface, and the negative surface is attached to the coating layer (2); the center of the strain layer (6) is collinear with the center of the adhesive layer (1), and the strain layer (6) is coated with the coating layer (2) around. The back adhesive paper (3) adopts a PP back adhesive paper (3); The material of the adhesive layer (1) is adhesive tape or rubber; The shape of the device for rapidly detecting the steam seal gap of a steam turbine comprises side adhesive edges (4) located on both sides and end surface adhesive edges (5) located between the two side adhesive edges (4); the side adhesive edges (4) and the end surface adhesive edges (5) are formed by integrated bending.

2. The device for detecting the steam seal gap of a steam turbine according to claim 1 is used for detecting the steam seal gap, characterized in that: The method comprises the following steps: S1: cleaning stains and oil stains on the steam seal structure; S2: after S1, uniformly applying red lead powder on the surface of the rotor and hoisting the rotor back to the working position of the rotor; S3: after S2, tearing off the back adhesive paper (3) of the device, adhering the device to the steam seal tooth, and pressing tightly; S4: after S3, hoisting the steam seal tooth with the device to the sealing structure, connecting the signal generator (8) with the display end (7) stably, keeping the working position of the rotor unchanged, and rotating 3-4 rounds; S5: after S4, hoisting out the rotor, checking the friction marks of the front surface of the adhesive layer (1) of the device with the red lead powder, preliminarily judging the size and corresponding position of the steam seal gap of the steam seal structure of the steam turbine, and quantitatively judging the size of the steam seal gap of the corresponding position in combination with the signal transmitted by the strain layer (6) to the display end (7).

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