A method for quickly repairing a flexible sealing ring for a nuclear power steam turbine on site

Abstract

The present invention discloses a method for rapidly repairing a flexible sealing ring for a nuclear power steam turbine. The method comprises the following steps: S1: cleaning and drying the area and surrounding area of ​​the flexible sealing ring to be repaired; S2: inspecting the extent of damage, preparing the necessary materials, and pre-treating the damaged area; S3: preparing a high-strength, wear-resistant suture thread with a diameter of 0.5 mm to 1.5 mm, and immersing the suture thread in a room-temperature vulcanized silicone rubber solution loaded with 35-40 kHz ultrasonic waves for 40-60 minutes; S4: threading the treated suture thread into a suture needle and suturing the damaged area of ​​the flexible sealing ring; S5: immersing the sutured area of ​​the flexible sealing ring in a room-temperature vulcanized silicone rubber solution loaded with 35-40 kHz ultrasonic waves for 30-70 minutes; S6: removing the treated flexible sealing ring and allowing it to stand in air for 20-36 hours; and S7: reinforcing the sutured area with a rubber sheet. The method utilizes a combination of physical suture connection and chemical connection to achieve rapid repair of a flexible sealing ring for a nuclear power steam turbine.

Description

Technical Field

[0001] The invention particularly relates to an on-site rapid repair method for a flexible sealing ring for a nuclear power steam turbine. Background Art

[0002] Flexible sealing rings for nuclear power steam turbines are installed between the low-pressure inner and outer cylinders of a nuclear power steam turbine, connecting them together. This prevents air from entering the low-pressure cylinder through the gap between the inner and outer cylinders, maintaining the vacuum in the low-pressure cylinder and condenser during unit operation. Flexible sealing rings for nuclear power steam turbines are generally made of EPDM rubber. Furthermore, because the flexible sealing rings are flexible, relative displacement between the low-pressure outer and inner cylinders during unit operation is absorbed by the flexible sealing rings, ensuring that changes in the unit's vacuum do not affect deformation of the low-pressure inner cylinder and maintain stable shafting operation.

[0003] When first installed, the sealing ring is a full-ring structure. The shafting must be connected before the nuclear power turbine is operational, making it impossible to remove the flexible sealing ring during subsequent maintenance. If the flexible sealing ring becomes damaged during operation, it cannot be returned to the original manufacturer for repair. Any industrial safety incident at a nuclear power plant results not only in direct economic losses but also in inestimable indirect losses. During operation, nuclear power plants must minimize industrial hazards and risks to the plant to a reasonable, feasible, and achievable minimum. Therefore, any damaged flexible sealing ring during nuclear power plant operation must be repaired to prevent it from impacting the safe operation of the nuclear power turbine. However, flexible sealing rings are manufactured using molds and hot vulcanization at the original manufacturer, which is not available at nuclear power plant sites. Simple cold bonding cannot ensure the service stability of the flexible sealing ring, thus compromising the safe, stable, and controlled operation of the nuclear power turbine. If the damaged area of ​​the flexible sealing ring expands during operation, it will directly lead to a decrease in the unit's vacuum level and unplanned unit shutdown, resulting in serious consequences. Therefore, a technology that can fully meet the requirements of fast and reliable on-site repair of flexible sealing rings is needed. Summary of the Invention

[0004] The purpose of the present invention is to address the deficiencies of the above-mentioned prior art and provide an on-site repair method for a flexible sealing ring for a nuclear power steam turbine by combining physical suture connection and chemical connection to achieve rapid repair.

[0005] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0006] A method for quickly repairing a flexible sealing ring for a nuclear power steam turbine on site, comprising the following steps:

[0007] S1: Clean and dry the location and surrounding area of ​​the flexible sealing ring that needs to be repaired;

[0008] S2: Check the extent of damage, prepare the necessary materials and pre-treat the damaged area;

[0009] S3: Prepare high-strength, wear-resistant sutures with a diameter of 0.5mm to 1.5mm, and immerse the sutures in

[0010] Immerse in room temperature vulcanized silicone rubber solution loaded with 35-40 kHz ultrasonic waves for 40-60 minutes;

[0011] S4: inserting the processed suture thread into the suture needle and suturing the damaged part of the flexible sealing ring;

[0012] S5: Immerse the area after the flexible sealing ring is sutured in a room temperature vulcanized silicone rubber solution loaded with 35-40 kHz ultrasonic waves for 30-70 minutes;

[0013] S6: Take out the treated flexible sealing ring and place it in air for 20 to 36 hours;

[0014] S7: Use rubber sheets to reinforce the seam area.

[0015] In said S2, checking the extent of damage includes checking whether the sealing ring is missing; preparing the required materials includes preparing repair materials to fill the missing parts; pre-treating the damaged area includes cleaning and drying the sealing ring, cutting off the surface of the damaged area along the edge of the damaged area, roughening and cleaning the cut edges, and accurately cutting the repair materials according to the cutting size and thickness, and roughening and cleaning them.

[0016] The suture thread in S3 is polyamide fiber or polyester fiber.

[0017] The rubber sheet is a silicone rubber sheet with a hardness of 60-75 Shore A.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. This invention utilizes a combination of physical suture and chemical bonding to rapidly repair flexible sealing rings used in nuclear power turbines. The combined suture and adhesive reinforcement techniques effectively improve the strength deficiencies inherent in cold bonding techniques. Impregnation and ultrasonic dispersion of the suture line and suture area enhance the bond between the suture line, damaged area, and the room-temperature vulcanized rubber solution. Reinforcement of the suture area with a rubber sheet effectively increases the strength of the damaged area, ensuring long-term, safe operation.

[0020] 2. The suture thread of the present invention is made of polyamide fiber or polyester fiber. By adopting this technical measure, the wear resistance, strength and service life of the repaired flexible sealing ring can be guaranteed.

[0021] 3. The rubber sheet of the present invention is a corrosion-resistant, high-temperature and high-pressure resistant silicone rubber sheet. By adopting this technical measure, the service life of the repaired flexible sealing ring can be further guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a flow chart of a method for quickly repairing a flexible sealing ring for a nuclear power steam turbine on site. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0024] Example 1

[0025] A rapid on-site repair method for flexible sealing rings used in nuclear power turbines involves immersing a 1.0 mm diameter polyamide fiber suture thread in a room-temperature vulcanized silicone rubber solution loaded with 36 kHz ultrasonic waves for 40 minutes. The damaged flexible sealing ring is then manually sutured. After suturing, the entire sutured area is placed in the room-temperature vulcanized silicone rubber solution loaded with 36 kHz ultrasonic waves for 50 minutes before removal. After stagnating in air for 36 hours, the sutured area is reinforced with a rubber sheet. In actual use, the rubber sheet is a silicone rubber sheet with a hardness of 65 Shore A. The suture thread is made of polyamide fiber, which has good mechanical strength, wear resistance, and corrosion resistance, ensuring the wear resistance, strength, and service life of the repaired flexible sealing ring.

[0026] like Figure 1 As shown, the specific steps of the on-site rapid repair method for the flexible sealing ring of the nuclear power steam turbine include:

[0027] S1: Clean and dry the location and surrounding area of ​​the flexible sealing ring that needs to be repaired;

[0028] S2: Check the extent of damage, prepare the necessary materials and pre-treat the damaged area;

[0029] S3: Prepare a high-strength, wear-resistant polyamide fiber suture with a diameter of 1.0 mm, and immerse the suture in a room temperature vulcanized silicone rubber solution loaded with 36 kHz ultrasonic waves for 40 minutes;

[0030] S4: inserting the processed suture thread into the suture needle and suturing the damaged part of the flexible sealing ring;

[0031] S5: Immerse the area after the flexible sealing ring is sutured in a room temperature vulcanized silicone rubber solution loaded with 36KHZ ultrasonic waves for 50 minutes;

[0032] S6: Take out the treated flexible sealing ring and place it in air for 36 hours;

[0033] S7: A silicone rubber sheet with a hardness of 65 Shore A was used to reinforce the suture area.

[0034] In S7, the specific steps of using the silicone rubber sheet to reinforce the stitching area include: preparing a silicone rubber sheet that can cover the stitching area according to the shape and size of the stitching area, and roughening and cleaning the bonding surface of the silicone rubber sheet; and then using room temperature vulcanized silicone rubber to bond and reinforce the stitching area.

[0035] The above-mentioned on-site repair method effectively improves the strength deficiency caused by cold bonding technology. The impregnation and ultrasonic dispersion of the seam line and seam area improves the bond between the seam line, damaged area, and the room temperature vulcanized rubber liquid. The reinforcement of the seam area with rubber sheet effectively improves the strength of the damaged area and ensures long-term safe operation.

[0036] Example 2

[0037] A rapid on-site repair method for a flexible sealing ring used in a nuclear power steam turbine comprises: immersing a 1.5 mm diameter polyamide fiber suture thread in a room-temperature vulcanized silicone rubber liquid loaded with 40 kHz ultrasonic waves for 50 minutes, then manually suturing the damaged gap in the flexible sealing ring. After suturing, the entire sutured area is placed in the room-temperature vulcanized silicone rubber liquid loaded with 40 kHz ultrasonic waves for 70 minutes before being removed and allowed to stand in air for 30 hours. Finally, the sutured area is reinforced with a silicone rubber sheet with a hardness of 72 (Shore A).

[0038] like Figure 1 As shown, the specific steps of the on-site rapid repair method for the flexible sealing ring of the nuclear power steam turbine include:

[0039] S1: Clean and dry the location and surrounding area of ​​the flexible sealing ring that needs to be repaired;

[0040] S2: Check the extent of damage, prepare the necessary materials and pre-treat the damaged area;

[0041] S3: Prepare a high-strength, wear-resistant polyamide fiber suture with a diameter of 1.5 mm, and immerse the suture in a room temperature vulcanized silicone rubber solution loaded with 40 kHz ultrasound for 50 minutes;

[0042] S4: inserting the processed suture thread into the suture needle and suturing the damaged part of the flexible sealing ring;

[0043] S5: Immerse the area after the flexible sealing ring is sutured in a room temperature vulcanized silicone rubber solution loaded with 40KHZ ultrasonic waves for 70 minutes;

[0044] S6: Take out the treated flexible sealing ring and place it in air for 30 hours;

[0045] S7: A silicone rubber sheet with a hardness of 72 Shore A was used to reinforce the suture area.

[0046] Example 3

[0047] A rapid on-site repair method for a flexible sealing ring used in a nuclear power steam turbine involves immersing a 1.3mm diameter polyester fiber suture thread in a room-temperature vulcanized silicone rubber liquid loaded with 38kHz ultrasonic waves for 60 minutes. The damaged notch in the flexible sealing ring is then manually sutured. After suturing, the entire sutured area is placed in a room-temperature vulcanized silicone rubber liquid loaded with 40kHz ultrasonic waves for 30 minutes before being removed. After standing in air for 20 hours, the sutured area is reinforced with a silicone rubber sheet with a hardness of 70 (Shore A).

[0048] like Figure 1 As shown, the specific steps of the on-site rapid repair method for the flexible sealing ring of the nuclear power steam turbine include:

[0049] S1: Clean and dry the location and surrounding area of ​​the flexible sealing ring that needs to be repaired;

[0050] S2: Check the extent of damage, prepare the necessary materials and pre-treat the damaged area;

[0051] Check the damage, including checking if the sealing ring is missing; prepare the necessary materials, including repair materials to fill in the missing parts; pre-treat the damaged area, including cleaning and drying the sealing ring, cutting the damaged surface along the edge, roughening and cleaning the cut edges, and accurately cutting the repair materials according to the cutting size and thickness, roughening and cleaning them;

[0052] S3: Prepare a polyester fiber suture with a diameter of 1.3 mm and immerse the suture in a room temperature vulcanized silicone rubber solution loaded with 38 kHz ultrasound for 60 minutes;

[0053] S4: inserting the processed suture thread into the suture needle and suturing the damaged part of the flexible sealing ring;

[0054] S5: Immerse the area after the flexible sealing ring is sutured in a room temperature vulcanized silicone rubber solution loaded with 38KHZ ultrasonic waves for 30 minutes;

[0055] S6: Take out the treated flexible sealing ring and place it in air for 20 hours;

[0056] S7: A silicone rubber sheet with a hardness of 70 Shore A was used to reinforce the suture area.

[0057] Among them, in S2, the position to be repaired is checked to confirm whether the repaired position is damaged by a crack. If it is a crack, the repaired position is cleaned and step S3 is directly started.

[0058] If the repaired area is partially missing, the following steps are required: inspect the damage, including checking for missing seal rings; prepare the necessary materials, including repair materials to complete the missing portion; pre-treat the damaged area, including cleaning and drying the seal ring, cutting along the damaged surface, roughening and cleaning the cut edges, and accurately cutting the repair material to size and thickness, roughening and cleaning it. Then proceed to step S3 and subsequent steps.

[0059] In S4, when suturing the damaged portion of the flexible sealing ring, the repair material accurately cut according to the cutting size and thickness can be directly sutured or pre-bonded to the damaged portion of the flexible sealing ring.

[0060] Example 4

[0061] A rapid on-site repair method for a flexible sealing ring used in a nuclear power steam turbine comprises: immersing a 0.6 mm diameter polyamide fiber suture thread in a room-temperature vulcanized silicone rubber liquid loaded with 38 kHz ultrasonic waves for 30 minutes, then manually suturing the damaged gap in the flexible sealing ring. After suturing, the entire sutured area is placed in the room-temperature vulcanized silicone rubber liquid loaded with 38 kHz ultrasonic waves for 60 minutes before being removed. After standing in air for 24 hours, the sutured area is reinforced with a silicone rubber sheet with a hardness of 63 (Shore A).

[0062] like Figure 1 As shown, the specific steps of the on-site rapid repair method for the flexible sealing ring of the nuclear power steam turbine include:

[0063] S1: Clean and dry the location and surrounding area of ​​the flexible sealing ring that needs to be repaired;

[0064] S2: Check the extent of damage, prepare the necessary materials and pre-treat the damaged area;

[0065] S3: Prepare a high-strength, wear-resistant polyamide fiber suture with a diameter of 0.6 mm, and immerse the suture in a room temperature vulcanized silicone rubber solution loaded with 38 kHz ultrasonic waves for 30 minutes;

[0066] S4: inserting the processed suture thread into the suture needle and suturing the damaged part of the flexible sealing ring;

[0067] S5: Immerse the area after the flexible sealing ring is sutured in a room temperature vulcanized silicone rubber solution loaded with 38KHZ ultrasonic waves for 60 minutes;

[0068] S6: Take out the treated flexible sealing ring and place it in air for 24 hours;

[0069] S7: A silicone rubber sheet with a hardness of 63 Shore A was used to reinforce the suture area.

[0070] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. It should be pointed out that any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for rapid on-site repair of a flexible sealing ring for a nuclear power steam turbine, characterized in that: The specific steps include: S1: Clean and dry the location and surrounding area of ​​the flexible sealing ring that needs to be repaired; S2: Check the extent of damage, prepare the necessary materials and pre-treat the damaged area; S3: preparing a high-strength, wear-resistant suture thread with a diameter of 0.5 mm to 1.5 mm, wherein the suture thread is made of polyamide fiber or polyester fiber; immersing the suture thread in a room temperature vulcanized silicone rubber solution loaded with 35-40 kHz ultrasonic waves for 40-60 minutes; S4: inserting the treated suture thread into a suture needle and suturing the damaged portion of the flexible sealing ring; S5: Immerse the area after the flexible sealing ring is sutured in a room temperature vulcanized silicone rubber solution loaded with 35-40 kHz ultrasonic waves for 30-70 minutes; S6: Take out the treated flexible sealing ring and place it in air for 20 to 36 hours; S7: The stitching area is reinforced with a rubber sheet; the rubber sheet is a silicone rubber sheet with a hardness of 60-75 Shore A.

2. The on-site rapid repair method for a flexible sealing ring for a nuclear power steam turbine according to claim 1, characterized in that: In said S2, checking the extent of damage includes checking whether the sealing ring is missing; preparing the required materials includes preparing repair materials to fill the missing parts; pre-treating the damaged area includes cleaning and drying the sealing ring, cutting off the surface of the damaged area along the edge of the damaged area, roughening and cleaning the cut edges, and accurately cutting the repair materials according to the cutting size and thickness, and roughening and cleaning them.

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