Generator stator bar hydrostatic test method and device with water leakage detection

Abstract

The invention relates to the technical field of generator hydraulic pressure test, in particular to a generator stator bar hydraulic pressure test method and device with water leakage detection, and the method comprises the steps: enabling a stator bar, an insulating water conduit, a water collecting pipe, a water inlet main pipe and a water outlet main pipe to be filled with water; pressurizing until the water pressure displayed by a pressure gauge exceeds 0.5 MPa; irreversible color-changing test paper is arranged at the position prone to water seepage; and the hydrostatic test is started. The irreversible color-changing test paper is arranged at each easy water seepage position, so that a water leakage point, especially a micro-seepage point, can be conveniently found, and the situation that the major defect of the generator is missed due to the fact that water is quickly volatilized after seeping and cannot be perceived is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of generator water pressure testing, and in particular to a generator stator wire rod water pressure testing method and device with water leakage detection. Background Art

[0002] The stator of a large generator is generally cooled by water. When conducting a preventive overhaul test on a large generator, it is required to pressurize the generator stator system including the water manifold, insulating water pipe and all stator bars at 0.5MPa and maintain the pressure for 8 hours (with a plug plate at the flange of the internal cooling water main), and the pressure does not drop or drops significantly. However, in actual operation, it is difficult to detect very slight water seepage at each joint. For example, if only a few drops of water seep out from the joint within 8 hours, the pressure gauge reading is likely to remain unchanged, and the water will evaporate quickly after seepage, making it difficult to detect. Summary of the invention

[0003] The purpose of the present invention is to address the defects of the prior art and provide a generator stator wire rod water pressure test method and device with leakage detection. By setting irreversible color-changing test paper at each water-prone seepage point, it is convenient to find leakage points, especially micro-seepage points.

[0004] In order to solve the above technical problems, in a first aspect, the present invention provides a generator stator bar water pressure test method with water leakage detection, comprising:

[0005] After the stator bars, insulating water pipes, water collection pipes, water inlet pipes and water outlet pipes are filled with water, pressurize them until the pressure gauge shows that the water pressure exceeds 0.5MPa;

[0006] Set up irreversible color-changing test paper at places prone to water seepage;

[0007] Begin the water pressure test.

[0008] Furthermore, the water-prone areas include the junction of the insulating water diversion pipe and the hand-wrapped insulation, the joint of the insulating water diversion pipe and the water collecting pipe, the flanges of the water inlet pipe and the water outlet pipe, and the valves of the water inlet pipe and the water outlet pipe.

[0009] Furthermore, the irreversible color change test paper includes release paper, absorbent paper, and base paper stacked in sequence, an adhesive is arranged between the release paper and the absorbent paper, the adhesive is arranged close to the end of the release paper, and a water-soluble pigment is arranged between the absorbent paper and the base paper.

[0010] Furthermore, the method for setting the irreversible color change test paper includes: tearing off the isolation paper, placing the absorbent paper toward the water-prone area, wrapping the irreversible color change test paper around the water-prone area, and bonding the two ends of the irreversible color change test paper with an adhesive.

[0011] Furthermore, the method of setting the irreversible color changing test paper at the junction of the insulating water pipe and the hand bag insulation includes: half of the irreversible color changing test paper wraps the hand bag insulation, and the other half of the irreversible color changing test paper wraps the insulating water pipe.

[0012] In some embodiments, before conducting a water pressure test, both ends of the generator are closed, and the air temperature in the generator chamber is adjusted by an air conditioner to indirectly keep the water temperature of the wire rods in the generator chamber stable. A fan is installed in the generator chamber to circulate air internally to ensure that the air temperature is uniform throughout the chamber. When the water temperature is consistent with the air temperature in the generator chamber, the water pressure test is started, the pressure value of the pressure gauge is read, and timing is started.

[0013] In some embodiments, the pressure gauge comprises a digital pressure gauge, two of which are provided, and the two pressure gauges are provided on the water inlet main pipe and the water outlet main pipe respectively;

[0014] After filling the stator bars, insulated water pipes, water collecting pipes, water inlet main pipes and water outlet main pipes with water and pressurizing them, compare the values ​​of the two pressure gauges. If the difference between the values ​​of the two pressure gauges is greater than 0.001MPa, the faulty pressure gauge should be replaced. During the water pressure test and at the end of the water pressure test, compare the values ​​of the two pressure gauges. If the difference between the values ​​of the two pressure gauges is greater than 0.005MPa, the faulty pressure gauge should be replaced.

[0015] In some embodiments, the time period for the hydrostatic test is selected from evening to morning.

[0016] In some embodiments, the method of filling the stator bars, the insulating water pipes, the water collecting pipes, the water inlet main pipes, and the water outlet main pipes with water and pressurizing them includes:

[0017] If the stator internal cooling water supply system can operate normally, first use the stator internal cooling water supply system to fill the stator wire rods, insulating water pipes, water collection pipes, water inlet pipes, and water outlet pipes with water, disassemble the flange connection between the stator internal cooling water supply system and the water inlet pipe and water outlet pipe, and install flange plugs on the water inlet pipe and water outlet pipe, connect the valve of the water inlet pipe to the hydraulic press, open the valve of the water inlet pipe, directly pressurize it with the hydraulic press, observe the pressure gauge, and when the water pressure exceeds 0.5MPa, stop pressurizing immediately, close the valve of the water inlet pipe, and maintain the pressure;

[0018] If the cooling water supply system in the stator cannot operate normally, disassemble the flange connection between the cooling water supply system in the stator and the water inlet pipe and the water outlet pipe, and install flange plugs on the water inlet pipe and the water outlet pipe, open the valves of the water inlet pipe and the water outlet pipe, connect the valve of the water inlet pipe to the hydraulic press, and use the hydraulic press to supply water to the stator of the generator until water comes out of the valve of the water outlet pipe, close the valve of the water outlet pipe, pressurize with the hydraulic press, observe the pressure gauge, and when the water pressure exceeds 0.5MPa, stop pressurizing immediately, close the valve of the water inlet pipe, and maintain the pressure.

[0019] In a second aspect, the present invention provides a generator stator wire rod water pressure test device with water leakage detection, including a pressure gauge, a hydraulic press, an air conditioner, a sealing cloth, and an irreversible color change test paper;

[0020] Two pressure gauges are provided, and the two pressure gauges are respectively arranged on the water inlet main pipe and the water outlet main pipe of the generator, and the two pressure gauges are used for mutual inspection and monitoring of the inlet and outlet water pressure values;

[0021] The hydraulic press is connected to the water inlet main pipe of the generator, and is used to pressurize through the water inlet main pipe, or to pressurize after filling the stator wire rod, the insulating water diversion pipe, the water collection pipe, the water inlet main pipe, and the water outlet main pipe with water;

[0022] The air conditioner is used to adjust the air temperature in the generator chamber, and the sealing cloth is arranged at both ends of the generator to seal the generator chamber and ensure the stability of the temperature in the generator chamber;

[0023] The irreversible color change test paper is used to be pasted to a water-prone part of the generator.

[0024] The beneficial effects of the present invention are:

[0025] 1. The present invention arranges irreversible color-changing test paper at the place where water is easy to seep. The irreversible color-changing test paper changes color when it comes into contact with water, which makes it easy to find the leakage point, especially the micro-seepage point, and avoids the situation where the water evaporates quickly after seeping out and cannot be detected, resulting in the major defects of the generator being missed.

[0026] 2. The water-prone areas of the present invention include the junction of the insulating water diversion pipe and the hand-wrapped insulation, the joint of the insulating water diversion pipe and the water collection pipe, the flanges of the water inlet pipe and the water outlet pipe, and the valves of the water inlet pipe and the water outlet pipe, wherein the joint of the insulating water diversion pipe and the water collection pipe, the flanges of the water inlet pipe and the water outlet pipe, and the valves of the water inlet pipe and the water outlet pipe are all connections between structures and are water-prone areas, while the connection between the insulating water diversion pipe and the stator wire rod is wrapped by hand-wrapped insulation, and an irreversible color-changing test paper cannot be directly set at the connection between the insulating water diversion pipe and the stator wire rod. Water leaking from the connection between the insulating water diversion pipe and the stator wire rod usually seeps out from the junction of the insulating water diversion pipe and the hand-wrapped insulation. Therefore, an irreversible color-changing test paper can be set at the junction of the insulating water diversion pipe and the hand-wrapped insulation to detect the sealing of the connection between the insulating water diversion pipe and the stator wire rod.

[0027] 3. The irreversible color-changing test paper of the present invention is different from the conventional irreversible color-changing test paper. The conventional irreversible color-changing test paper includes absorbent paper, base paper, and release paper stacked in sequence, a water-soluble pigment is arranged between the absorbent paper and the base paper, an adhesive is arranged between the base paper and the release paper, and the adhesive covers the entire base paper. When the conventional irreversible color-changing test paper is bonded to an insulating water pipe or other structure, the adhesive will adhere to the insulating water pipe, which is difficult to clean, and the absorbent paper is located at the outermost layer, and the seeped water needs to contact the outermost layer to cause the absorbent paper to change color. However, the water seeping from each water-prone place first contacts the innermost layer of the irreversible color-changing test paper, and the conventional irreversible color-changing test paper may not be able to detect the seepage. After the irreversible color-changing test paper of the present invention is fixed to a place prone to water seepage, the absorbent paper is located in the innermost layer, and the seeped water can directly contact the absorbent paper, thereby ensuring the detection effect of the irreversible color-changing test paper, and the adhesive is only arranged close to one end of the isolation paper, and the adhesive will not stick to the insulating water pipe or other structures.

[0028] 4. Since the insulating water pipe is arranged 360 degrees at the end of the generator, water seeping from the junction of the insulating water pipe and the hand-wrapped insulation may flow along the insulating water pipe, or flow along the outer surface of the hand-wrapped insulation, or drip directly. The irreversible color-changing test paper at the junction of the insulating water pipe and the hand-wrapped insulation of the present invention wraps half of the hand-wrapped insulation and the other half of the insulating water pipe, so that water seepage at the junction of the insulating water pipe and the hand-wrapped insulation arranged at any angle can be detected.

[0029] 5. The present invention closes both ends of the generator and uses air conditioning and fans to maintain a stable air temperature in the generator chamber, so that the water temperature in the stator bars, insulating water pipes, water collection pipes, water inlet main pipes, and water outlet main pipes is always equal to the air temperature in the chamber, thereby avoiding the influence of water temperature changes on the test.

[0030] 6. The pressure gauge of the present invention adopts a digital pressure gauge, which can avoid errors in manual readings and changes in readings caused by mechanical jitter of the pressure gauge. By setting two pressure gauges, the two pressure gauges can check each other. If there is no difference in the values ​​between the two pressure gauges, pressure gauge failure can be ruled out, thereby avoiding the influence of pressure gauge failure on the water pressure test results.

[0031] 7. The water pressure test of the present invention limits the test time period, that is, from evening to morning. From evening to morning is a time period when the external environment temperature fluctuates less, which is beneficial to ensure the stability of the temperature inside the generator chamber.

[0032] 8. When the stator bars, insulating water pipes, water collecting pipes, water inlet main pipes and water outlet main pipes are filled with water, the cooling water supply system in the stator can be directly used, which is beneficial to improving the efficiency of the water pressure test. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the structure after the pressure gauge is installed in the present invention;

[0034] Figure 2 This is a schematic diagram of water injection using the stator internal cooling water supply system of the present invention;

[0035] Figure 3 It is a schematic diagram of the present invention using a hydraulic press to press;

[0036] Figure 4 It is a schematic diagram of the connection structure between the water collecting pipes at both ends of the generator and the stator wire rods of the present invention;

[0037] Figure 5 It is a schematic diagram of the connection structure between the water collecting pipe and the stator wire bar of the present invention;

[0038] Figure 6 It is a cross-sectional view of an irreversible color-changing test paper in the prior art;

[0039] Figure 7 It is a usage state diagram of the irreversible color change test paper in the prior art;

[0040] Figure 8 This is a water drop flow diagram when the tee of the present invention leaks;

[0041] Fig. 9 is a cross-sectional view of the irreversible color-changing test paper of the present invention;

[0042] Fig.10 It is a structural schematic diagram of the irreversible color-changing test paper of the present invention;

[0043] Fig.11 A schematic diagram of the pasting of the irreversible color-changing test paper at the junction of the insulating water diversion pipe and the hand bag insulation of the present invention;

[0044] Fig.12 This is a schematic diagram of the structure of the present invention using air conditioning to adjust the temperature inside the generator chamber.

[0045] Figure numerals: water inlet main pipe 1; water outlet main pipe 2; stator wire rod 3; inner wire rod 31; outer wire rod 32; insulating water pipe 4; water collecting pipe 5; pressure gauge 6; irreversible color change test paper 7; isolation paper 71; absorbent paper 72; base paper 73; adhesive 74; water-soluble pigment 75; serrated pre-torn cut 76; stator internal cooling water supply system 8; first valve 9; second valve 10; hydraulic press 11; flange plug 12; hand-wrapped insulation 13; copper tube 14; tee 15; air conditioner 16; sealing cloth 17; water and electricity connector 18. DETAILED DESCRIPTION

[0046] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0047] The present invention provides a generator stator wire rod water pressure test method with water leakage detection, comprising:

[0048] S1, such as Figure 1 As shown, an annular water collecting pipe 5 is arranged at both ends of the generator, and the two water collecting pipes 5 are respectively connected to the two ends of the stator wire rod 3, and the two water collecting pipes 5 are respectively connected to the water inlet mother pipe 1 and the water outlet mother pipe 2, and flanges are arranged on the water inlet mother pipe 1 and the water outlet mother pipe 2 for connecting with the stator internal cooling water supply system 8, and the stator internal cooling water supply system 8 is used to circulate and provide cooling water to the stator wire rod 3, and a first valve 9 is arranged on the water inlet mother pipe 1, and a second valve 10 is arranged on the water outlet mother pipe 2.

[0049] Pressure gauges 6 are installed on both the water inlet main pipe 1 and the water outlet main pipe 2 , wherein the pressure gauges 6 are digital pressure gauges 6 .

[0050] It should be noted that due to the mechanical vibration of the pressure gauge 6, the reading angle of the pressure gauge 6, and the fault of the pressure gauge 6 itself, it is inevitable that the start and end values ​​of the pressure gauge 6 will change. When the pressure value changes, it is difficult to determine whether the generator stator bar 3 is leaking. The core of the water pressure test is that after 8 hours of pressure maintenance, the pressure does not change, indicating that the system is not leaking. If the pressure changes, it is impossible to accurately determine whether the system is leaking because there are many reasons for the pressure change.

[0051] Compared with the prior art that only installs a mechanical pressure gauge 6 on the water inlet main pipe 1 or the water outlet main pipe 2, the present invention uses a digital pressure gauge 6 to avoid errors in manual readings and changes in readings caused by mechanical vibration of the pressure gauge 6. The two pressure gauges 6 can check each other, and the lack of difference in the values ​​between the two pressure gauges 6 can rule out the failure of the pressure gauge 6, thereby avoiding the impact of the failure of the pressure gauge 6 on the water pressure test results. In addition, the two pressure gauges 6 can conveniently monitor the inlet and outlet water pressure values, providing an additional reference data for operation and maintenance analysis.

[0052] S2, such as Figure 2 As shown, if the stator internal cooling water supply system 8 can operate normally, the stator bar 3, the insulating water pipe 4, the water collection pipe 5, the water inlet main pipe 1, and the water outlet main pipe 2 are first filled with water through the stator internal cooling water supply system 8, as shown in FIG. Figure 3 As shown, disassemble the flange connection between the stator internal cooling water supply system 8 and the water inlet main pipe 1 and the water outlet main pipe 2, and install the flange plug 12 on the water inlet main pipe 1 and the water outlet main pipe 2, open the first valve 9, connect the first valve 9 of the water inlet main pipe 1 to the hydraulic press 11, directly pressurize through the hydraulic press 11, observe the pressure gauge 6, and when the water pressure exceeds 0.5MPa, stop pressurizing immediately, close the first valve 9 of the water inlet main pipe 1, and maintain the pressure;

[0053] like Figure 3 As shown, if the cooling water supply system 8 in the stator cannot operate normally, disassemble the flange connection between the cooling water supply system 8 in the stator and the water inlet main pipe 1 and the water outlet main pipe 2, and install the flange plug 12 on the water inlet main pipe 1 and the water outlet main pipe 2, open the first valve 9 and the second valve 10, connect the first valve 9 to the hydraulic press 11, and supply water to the generator stator through the hydraulic press 11 until water comes out of the second valve 10, close the second valve 10, pressurize through the hydraulic press 11, observe the pressure gauge 6, and when the water pressure exceeds 0.5MPa, stop pressurizing immediately, close the first valve 9, and maintain the pressure.

[0054] It should be noted that the cooling water supply system 8 in the stator flows water quickly, while the use of the hydraulic press 11 for water injection requires a long waiting time and requires a large amount of clean water to be transported to the hydraulic press 11 for pumping. Therefore, the cooling water supply system 8 in the stator is preferably used to fill the stator wire rods 3, the insulating water pipes 4, the water collecting pipes 5, the water inlet main pipe 1, and the water outlet main pipe 2 with water, which is beneficial to improving the efficiency of the water pressure test.

[0055] S3. After the pressure test is completed, compare the values ​​of the two pressure gauges 6. If the value difference between the two pressure gauges 6 is greater than 0.001MPa, the faulty pressure gauge 6 should be replaced, otherwise proceed to the next step. One of the pressure gauges 6 can be replaced. If the value difference between the replaced pressure gauge 6 and the unreplaced pressure gauge 6 is not greater than 0.001MPa, it means that the faulty pressure gauge 6 has been replaced.

[0056] S4. Irreversible color change test paper 7 is installed at places where water is easy to seep, including the junction of the insulating water pipe 4 and the hand-wrapped insulation 13, the joint of the insulating water pipe 4 and the water collecting pipe 5, the flanges of the water inlet main pipe 1 and the water outlet main pipe 2, and the valves of the water inlet main pipe 1 and the water outlet main pipe 2.

[0057] It should be noted that the joints of the insulated water diversion pipe 4 and the water collection pipe 5, the flanges of the water inlet pipe 1 and the water outlet pipe 2, and the valves of the water inlet pipe 1 and the water outlet pipe 2 are all in conventional positions, while the connection between the water collection pipe 5 and the stator bar 3 is relatively special, such as Figure 4 As shown in FIG. 1 , the water collecting pipes 5 and the stator bars 3 at the left and right ends of the generator are shown. Figure 5 As shown, the stator wire bar 3 includes an inner wire bar 31 and an outer wire bar 32, the water collecting pipe 5 is connected to the first end of the tee 15 through the insulating water diversion pipe 4, and the second end and the third end of the tee 15 are respectively connected to the water and electricity joints 18 of the inner wire bar 31 and the outer wire bar 32 through the copper tube 14. Since the water and electricity joints 18 are pressed and welded at the later stage during manufacturing, the water and electricity joints 18 are also one of the places that are prone to water leakage (that is, the joints between the stator wire bar 3 and the water and electricity joints 18, the water and electricity joints 18 themselves, and the connection between the water and electricity joints 18 and the copper tube 14 are all prone to water leakage). The water and electricity joints 18, the copper tube 14, the tee 15 and part of the tube body of the insulating water diversion pipe 4 are all wrapped with hand-wrapped insulation 13. If water seepage occurs at the tee 15 and the water and electricity joints 18, it cannot be directly observed. The present invention can detect whether water seepage occurs at the tee 15 and the water and electricity joint 18 by arranging an irreversible color change test paper 7 at the junction of the insulating water diversion pipe 4 and the hand-wrapped insulation 13.

[0058] It should also be noted that if Figure 4 As shown, the water collecting pipe 5 is annular, and the insulating water diversion pipe 4 is evenly distributed along 360°. Therefore, there is a situation where the insulating water diversion pipe 4 is above the tee 15. Since the copper tube 14 and the water and electricity joint 18 are hard structures, the insulating water diversion pipe 4 is a non-metallic plastic tube with a soft texture. The wrapping between the hand-wrapped insulation 13 and the water and electricity joint 18, the tee 15 and the copper tube 14 is extremely tight, while the wrapping between the hand-wrapped insulation 13 and the insulating water diversion pipe 4 is relatively soft. Therefore, even if the insulating water diversion pipe 4 is above the tee 15, the water seeping from the tee 15 will not flow away from the water and electricity joint 18, but will flow upward from between the hand-wrapped insulation 13 and the insulating water diversion pipe 4.

[0059] In addition, due to long-term vibration or raw material defects, cracks and water leaks inside the stator bar 3, and finally seeps out from the junction of the insulating water pipe 4 and the hand-wrapped insulation 13. This is because there is a layer of main insulation wrapped very tightly outside the stator bar 3. In most cases, after water seeps out of the stator bar 3, it cannot penetrate the main insulation, and can only diffuse and penetrate forward along the joint surface of the stator bar 3 and the main insulation, and finally comes to the joint between the water box and the stator bar 3 and emerges into the hand-wrapped insulation 13, and gradually penetrates to the junction of the insulating water pipe 4 and the hand-wrapped insulation 13.

[0060] Therefore, the present invention only needs to set the irreversible color change test paper 7 at the junction of the insulating water pipe 4 and the hand-wrapped insulation 13 to detect whether water seepage occurs at the tee 15 and the water-electricity joint 18 and the stator wire rod 3.

[0061] like Figure 6 As shown in the figure, the structure of a conventional irreversible color change test paper is shown. The conventional irreversible color change test paper includes absorbent paper 72, base paper 73, and release paper 71 stacked in sequence. A red or other colored water-soluble pigment 75 is arranged between the absorbent paper 72 and the base paper 73. An adhesive 74 is arranged between the base paper 73 and the release paper 71. The adhesive 74 covers the entire base paper 73. When the conventional irreversible color change test paper is bonded to the insulating water pipe 4 or other structures, the adhesive 74 will adhere to the insulating water pipe 4, making it difficult to clean. Figure 7 As shown, the absorbent paper 72 is located at the outermost layer. The seeping water needs to contact the outermost layer to cause the absorbent paper 72 to change color. However, the water seeping from each water-permeable location first contacts the innermost layer of the irreversible color-changing test paper 7. Conventional irreversible color-changing test paper may not be able to detect water seepage. Figure 8 As shown, taking the junction of the insulating water pipe 4 and the hand-wrapped insulation 13 as an example, when the tee 15 is located above the insulating water pipe 4, the water seeping from the tee 15 will flow out from the junction of the insulating water pipe 4 and the hand-wrapped insulation 13 and continue to flow down along the insulating water pipe 4. When the tee 15 is located below the insulating water pipe 4, the water seeping from the tee 15 will flow out from the junction of the insulating water pipe 4 and the hand-wrapped insulation 13 and flow down along the outer surface of the hand-wrapped insulation 13. When the insulating water pipe 4 is water When arranged horizontally, water seeping from the tee 15 may drip directly from the junction of the insulating water pipe 4 and the hand-wrapped insulation 13. If a conventional irreversible color-changing test paper is fixed on the junction of the insulating water pipe 4 and the hand-wrapped insulation 13, water seepage may not be detected in any of the three situations. If a conventional irreversible color-changing test paper is fixed on the insulating water pipe 4, water seepage can only be detected in the first situation. If a conventional irreversible color-changing test paper is fixed on the hand-wrapped insulation 13, water seepage can only be detected in the second situation.

[0062] In order to ensure the detection effect of the irreversible color change test paper 7, the present invention improves the structure of the irreversible color change test paper 7: Fig. 9As shown, the irreversible color change test paper 7 of the present invention includes a release paper 71, an absorbent paper 72, and a base paper 73 stacked in sequence, an adhesive 74 is arranged between the release paper 71 and the absorbent paper 72, and the adhesive 74 is arranged close to the end of the release paper 71. A water-soluble pigment 75 is arranged between the absorbent paper 72 and the base paper 73. When in use, the release paper 71 is torn off, and the side where the absorbent paper 72 is arranged is facing the junction of the insulating water guide pipe 4 and the hand-wrapped insulation 13, and one end of the irreversible color change test paper 7 is connected and fixed to the other end through the adhesive 74, so that the irreversible color change test paper 7 is fixed at the junction of the insulating water guide pipe 4 and the hand-wrapped insulation 13, half of the irreversible color change test paper 7 wraps the hand-wrapped insulation 13, and the other half of the irreversible color change test paper 7 wraps the insulating water guide pipe 4, as shown in FIG. Fig.11 As shown. The isolation paper 71 can be made of transparent plastic paper or release paper. Before pasting, the pasting area should be cleaned and free of oil stains and dried.

[0063] After the irreversible color-changing test paper 7 of the present invention is fixed to the place where water is easily seeped, the absorbent paper 72 is located in the innermost layer. No matter what the direction of the insulating water pipe 4 is, as long as it leaks from the junction of the insulating water pipe 4 and the hand-wrapped insulation 13, it will inevitably directly contact the absorbent paper 72, thereby ensuring the detection effect of the irreversible color-changing test paper 7, and the adhesive 74 is only arranged near one end of the isolation paper 71, and the adhesive 74 will not stick to the insulating water pipe 4 or other structures.

[0064] like Fig.10 As shown, the irreversible color-changing test paper 7 can be made into a roll structure, and a serrated pre-tear cut 76 is provided between two adjacent irreversible color-changing test papers 7 for easy use.

[0065] S5, such as Fig.12 As shown, both ends of the generator are closed, and the air temperature in the generator chamber is adjusted by the air conditioner 16, so that the water temperature of the wire rods in the generator chamber is indirectly kept stable, and a fan is installed in the generator chamber to circulate the air internally to ensure that the air temperature in the chamber is uniform. When the water temperature is consistent with the air temperature in the generator chamber, the water pressure test can be started.

[0066] Among them, a closed cloth 17 can be used to close the two ends of the generator. Magnets can be sewn on the edge of the closed cloth 17 so that the closed cloth 17 can be directly adsorbed on the end cover of the generator. The closed cloth 17 should be reserved for the air inlet and outlet holes of the air conditioner 16 pipe.

[0067] The prior art has no method to solve the problem that the test fails or there is a water leak due to the change of water temperature caused by the change of ambient temperature, which further causes the change of water pressure (even the pressure change is large). The present invention uses the air conditioner 16, the sealing cloth 17, and the fan to perform constant temperature treatment on the generator chamber, thus avoiding the influence of the water temperature change on the test.

[0068] S6, start timing, conduct water pressure test, copy the value of pressure gauge 6 every one hour, compare the values ​​of two pressure gauges 6, if the difference between the values ​​of two pressure gauges 6 is greater than 0.005MPa, replace the faulty pressure gauge 6. Compare the value of pressure gauge 6 corresponding to the eighth hour with the value of pressure gauge 6 in step S3, if the change is within 0.001MPa, and all test papers have no color change, it means that the water pressure test is qualified.

[0069] In order to further improve the accuracy of the water pressure test, the time period for the water pressure test is preferably from evening to morning, for example, from 9 pm to 5 am the next day. The external ambient temperature fluctuates less, which is conducive to ensuring the stability of the temperature inside the generator chamber. The second time period is from morning to night. It cannot be selected from noon to evening, or from midnight to daytime.

[0070] The present invention also provides a generator stator wire rod water pressure test device with water leakage detection, comprising a pressure gauge 6, a hydraulic press 11, an air conditioner 16, a sealing cloth 17, and an irreversible color change test paper 7;

[0071] Two pressure gauges 6 are provided, and the two pressure gauges 6 are arranged on the water inlet main pipe 1 and the water outlet main pipe 2 of the generator respectively, and the two pressure gauges 6 are used for mutual inspection and monitoring of the inlet and outlet water pressure values;

[0072] The hydraulic press 11 is connected to the water inlet main pipe 1 of the generator, and is used to pressurize through the water inlet main pipe 1, or to pressurize after filling the stator bar 3, the insulating water pipe 4, the water collecting pipe 5, the water inlet main pipe 1, and the water outlet main pipe 2 with water;

[0073] The air conditioner 16 is used to adjust the air temperature in the generator chamber. The sealing cloth 17 is arranged at both ends of the generator to seal the generator chamber and ensure the stability of the temperature in the generator chamber.

[0074] The irreversible color change test paper 7 is used to be pasted to the water-prone part of the generator.

[0075] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for hydraulic testing of generator stator bars with water leakage detection, characterized in that: include: After the stator wire rod (3), the insulating water pipe (4), the water collecting pipe (5), the water inlet main pipe (1) and the water outlet main pipe (2) are filled with water, the water pressure is increased until the pressure gauge (6) shows that the water pressure exceeds 0.5 MPa; An irreversible color change test paper (7) is provided at a place where water easily seeps; Begin the water pressure test.

2. The generator stator bar water pressure test method with water leakage detection according to claim 1 is characterized in that: The water-prone areas include the junction of the insulating water diversion pipe (4) and the hand-wrapped insulation (13), the joint of the insulating water diversion pipe (4) and the water collection pipe (5), the flanges of the water inlet main pipe (1) and the water outlet main pipe (2), and the valves of the water inlet main pipe (1) and the water outlet main pipe (2).

3. The generator stator wire bar water pressure test method with water leakage detection according to claim 2 is characterized in that: The irreversible color change test paper (7) comprises a release paper (71), an absorbent paper (72), and a base paper (73) stacked in sequence, an adhesive (74) is arranged between the release paper (71) and the absorbent paper (72), the adhesive (74) is arranged close to the end of the release paper (71), and a water-soluble pigment (75) is arranged between the absorbent paper (72) and the base paper (73).

4. The generator stator wire bar water pressure test method with water leakage detection according to claim 3 is characterized in that: The method for setting the irreversible color change test paper (7) comprises: tearing off the isolation paper (71), placing the absorbent paper (72) toward the water-prone area, wrapping the irreversible color change test paper (7) around the water-prone area, and bonding the two ends of the irreversible color change test paper (7) with an adhesive (74).

5. The generator stator wire bar water pressure test method with water leakage detection according to claim 3 is characterized in that: A method for arranging an irreversible color-changing test paper (7) at the junction of an insulating water diversion pipe (4) and a hand-wrapped insulation (13) comprises: half of the irreversible color-changing test paper (7) wraps the hand-wrapped insulation (13), and the other half of the irreversible color-changing test paper (7) wraps the insulating water diversion pipe (4).

6. The generator stator wire bar water pressure test method with water leakage detection according to any one of claims 1 to 5, characterized in that: Before the water pressure test, both ends of the generator are closed, and the air temperature in the generator chamber is adjusted by using an air conditioner (16), so that the water temperature of the wire rods in the generator chamber is indirectly kept stable. A fan is installed in the generator chamber to circulate the air internally to ensure that the air temperature in the chamber is uniform. When the water temperature is consistent with the ambient air temperature in the generator chamber, the water pressure test is started, the pressure value of the pressure gauge (6) is read, and the timing is started.

7. The generator stator wire bar water pressure test method with water leakage detection according to any one of claims 1 to 5, characterized in that: The pressure gauge (6) comprises a digital pressure gauge (6), two of the pressure gauges (6) are provided, and the two pressure gauges (6) are respectively provided on the water inlet main pipe (1) and the water outlet main pipe (2); After the stator bars (3), the insulating water pipe (4), the water collecting pipe (5), the water inlet main pipe (1) and the water outlet main pipe (2) are filled with water and pressurized, the values ​​of the two pressure gauges (6) are compared. If the difference between the values ​​of the two pressure gauges (6) is greater than 0.001 MPa, the faulty pressure gauge (6) should be replaced. During the water pressure test and at the end of the water pressure test, the values ​​of the two pressure gauges (6) are compared. If the difference between the values ​​of the two pressure gauges (6) is greater than 0.005 MPa, the faulty pressure gauge (6) should be replaced.

8. The generator stator wire bar water pressure test method with water leakage detection according to any one of claims 1 to 5, characterized in that: The time period for the water pressure test is selected from evening to morning.

9. The generator stator wire bar water pressure test method with water leakage detection according to any one of claims 1 to 5, characterized in that: The method of filling the stator wire rod (3), the insulating water guide pipe (4), the water collecting pipe (5), the water inlet main pipe (1), and the water outlet main pipe (2) with water and pressurizing the same comprises: If the stator internal cooling water supply system (8) can operate normally, first use the stator internal cooling water supply system (8) to fill the stator wire rod (3), the insulating water pipe (4), the water collecting pipe (5), the water inlet main pipe (1), and the water outlet main pipe (2) with water, disassemble the flange connection between the stator internal cooling water supply system (8) and the water inlet main pipe (1) and the water outlet main pipe (2), and install the flange plug (12) on the water inlet main pipe (1) and the water outlet main pipe (2), connect the valve of the water inlet main pipe (1) to the hydraulic press (11), open the valve of the water inlet main pipe (1), directly pressurize it through the hydraulic press (11), observe the pressure gauge (6), and when the water pressure exceeds 0.5MPa, immediately stop pressurizing, close the valve of the water inlet main pipe (1), and maintain the pressure; If the stator internal cooling water supply system (8) cannot operate normally, the flange connection between the stator internal cooling water supply system (8) and the water inlet main pipe (1) and the water outlet main pipe (2) is disassembled, and flange plugs (12) are installed on the water inlet main pipe (1) and the water outlet main pipe (2). The valves of the water inlet main pipe (1) and the water outlet main pipe (2) are opened, and the valve of the water inlet main pipe (1) is connected to the hydraulic press (11). Water is supplied to the generator stator through the hydraulic press (11) until water oozes out of the valve of the water outlet main pipe (2). The valve of the water outlet main pipe (2) is closed, and pressure is applied through the hydraulic press (11). The pressure gauge (6) is observed. When the water pressure exceeds 0.5 MPa, the pressurization is stopped immediately, and the valve of the water inlet main pipe (1) is closed to maintain the pressure.

10. A generator stator wire rod water pressure test device with water leakage detection, characterized in that: It includes a pressure gauge (6), a hydraulic press (11), an air conditioner (16), a sealing cloth (17), and an irreversible color-changing test paper (7); Two pressure gauges (6) are provided, and the two pressure gauges (6) are respectively arranged on the water inlet main pipe (1) and the water outlet main pipe (2) of the generator, and the two pressure gauges (6) are used for mutual inspection and monitoring of the inlet and outlet water pressure values; The hydraulic press (11) is connected to the water inlet main pipe (1) of the generator and is used to pressurize the water through the water inlet main pipe (1), or to pressurize the stator wire rod (3), the insulating water guide pipe (4), the water collecting pipe (5), the water inlet main pipe (1) and the water outlet main pipe (2) after filling them with water; The air conditioner (16) is used to adjust the air temperature in the generator chamber, and the sealing cloth (17) is arranged at both ends of the generator in a sealing manner to seal the generator chamber and ensure that the temperature in the generator chamber is stable; The irreversible color change test paper (7) is used to be pasted to a water-prone part of the generator.

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