Method for manufacturing and testing double-cone metal seal rings for nuclear reactors

Abstract

The present application belongs to the technical field of seal manufacturing and inspection, and particularly relates to a manufacturing and inspection method of a double-cone type metal seal ring for a nuclear reactor. The manufacturing and inspection method of the double-cone type metal seal ring for the nuclear reactor comprises the following steps: S110, preparing a plate material of a predetermined size; S120, turning a front end face; S130, turning a back end face; S210, performing hardness, air tightness, water pressure and thermal cycle test detection on the manufactured double-cone type metal seal ring. Through the improvement of the manufacturing process and the evaluation standards of the hardness, air tightness, water pressure and thermal cycle test, the performance of the double-cone type metal seal ring can be effectively verified, the frequent replacement due to the quality problems of the double-cone type metal seal ring can be avoided, and the production efficiency of the nuclear power plant is improved.

Description

Technical Field

[0001] This invention belongs to the field of sealing component manufacturing and inspection technology, specifically relating to a method for manufacturing and inspecting a double-cone metal sealing ring for nuclear reactors. Background Technology

[0002] The thermocouple mechanical seal of a nuclear reactor pressure vessel is a crucial component of the main system of a pressurized water reactor nuclear power unit. It serves as the primary pressure boundary, and its main function is to maintain the integrity of the primary pressure boundary. During reactor operation, the pressure vessel withstands the high temperature (≥310℃), high pressure (≥15.5MPa), and water flow impact of the primary boric acid solution. The thermocouple mechanical seal mainly includes mechanical components such as a cup-shaped metal sealing ring, a double-cone metal sealing ring, a male flange, and clamps. Among these, the double-cone metal sealing ring, facing high temperature, high pressure, and significant vibration conditions, experiences a significant decrease in sealing effectiveness, making it difficult to meet the normal operating requirements of the thermocouple mechanical seal of the nuclear reactor pressure vessel. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art by providing a method for manufacturing and inspecting a double-cone metal sealing ring for nuclear reactors. Through improvements in the manufacturing process and rigorous defect inspection of the finished product, the finished product meets the requirements of the operating conditions.

[0004] To solve the above problems, the technical solution of the present invention is as follows: a method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor, the method comprising the following steps:

[0005] S110: Material preparation, preparing sheet metal of the predetermined size;

[0006] S120: Positive end face turning;

[0007] S121: Clamp one end of the sheet metal using a clamp;

[0008] S122: Drill and bore the inner hole to the predetermined size;

[0009] S123: Turn the outer diameter of the disc to the predetermined size;

[0010] S124: The spherical surface on the machine is adjusted to the predetermined size;

[0011] S130: Reverse end face turning;

[0012] S131: Clamp the disk with a fixture;

[0013] S132: The spherical surface and overall length of the vehicle are up to the predetermined dimensions;

[0014] S210: The manufactured double-cone metal sealing ring is tested for hardness, air tightness, water pressure, and thermal cycling.

[0015] S211: Hardness Test

[0016] A double-cone metal sealing ring was selected for hardness testing, and the test was conducted in accordance with GB / T4340.1-2009 "Metallic Materials - Vickers Hardness Test - Part 1: Test Method". During the test, the sample was clamped in a vise, with the indenter axis perpendicular to the sample surface. The load was selected by rotating the handwheel to HV0.01, and the load was set to 0.098 N. The test was conducted by observing through the eyepiece, operating the cross-shaped worktable, selecting an appropriate loading point, and then starting the program to perform the Vickers hardness test. The Vickers hardness HV1 was used as the evaluation criterion, and HV1 ≥ 335 was considered as passing the test.

[0017] S212: Air tightness test

[0018] The airtightness test uses a double-cone metal seal ring airtightness test fixture and a double-cone metal seal ring airtightness test device; the leakage rate of helium leaking from the double-cone metal seal ring is measured by a helium mass spectrometer leak detector; the leakage rate value is used as the evaluation basis, and the leakage rate ≤10-6Pa.m3 / s is considered as qualified.

[0019] S213: Hydrostatic Test

[0020] The hydrostatic test uses a double-cone metal seal ring hydrostatic test fixture and a double-cone metal seal ring hydrostatic test system; the sealing condition of the double-cone metal seal ring is checked under a maximum water pressure of 25.8MPa, and the test is considered to be qualified if there is no visible leakage and the pressure drop does not exceed 0.1MPa;

[0021] S214: Thermal cycling test

[0022] The thermal cycling test uses a double-cone metal seal thermal cycling test fixture and a double-cone metal seal thermal cycling test system; under the hot working conditions of temperature ≥310℃ and pressure ≥15.5MPa, the test is cycled five times, and the absence of visible leakage is considered as passing the inspection.

[0023] The plate material mentioned in step S110 is a disc with a diameter of 110 x 22 mm.

[0024] In step S121, the clamp holds the disk in a direction extending 6mm from one end to the other.

[0025] The inner diameter of the drill boring machine in step S122 is Φ77.8mm.

[0026] The outer diameter of the machine disc mentioned in step S123 is Φ107.95mm.

[0027] The outer diameter of the upper spherical surface is Φ84.3mm~Φ84.4mm, and the height of the upper spherical surface is 6.35mm~6.36mm.

[0028] The sheet material, by weight percentage, comprises: carbon: ≤0.07%, chromium: 15% to 17.5%, nickel: 3% to 5%, silicon: ≤1%, manganese: ≤1%, sulfur: ≤0.03%, phosphorus: ≤0.04%, copper: 3% to 5%, niobium: 0.15% to 0.45%, with the remainder being iron.

[0029] The significant advantage of this invention is that the manufacturing and inspection method for a nuclear reactor double-cone metal sealing ring described herein, by improving the manufacturing process and using evaluation standards such as hardness, airtightness, water pressure, and thermal cycling tests, can effectively verify the performance of the double-cone metal sealing ring, avoid frequent replacements due to quality problems of the double-cone metal sealing ring, and improve the production efficiency of nuclear power plants. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the manufacturing and inspection method of a double-cone metal sealing ring for a nuclear reactor according to the present invention;

[0031] Figure 2 This is a schematic diagram of a double-cone metal sealing ring structure;

[0032] In the diagram: 100, double-cone metal sealing ring; 110, disc; 120, upper spherical surface; 130, lower spherical surface. Detailed Implementation

[0033] The technical solutions of the invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without creative effort are within the scope of the invention.

[0034] In the description of this invention, it should be noted that the use of terms such as "above" to indicate orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings and is only for the purpose of facilitating and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0035] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "setting," "installation," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] like Figure 2 As shown, the double-cone metal sealing ring 100 includes a disc 110, an upper spherical surface 120 and a lower spherical surface 130. The middle part of the double-cone metal sealing ring 100 is a cylindrical structure, with an upper spherical surface 120 at the left end and a lower spherical surface 130 at the right end. The disc 110 is located at the right end of the lower spherical surface 130.

[0038] like Figure 1 As shown, a method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor includes the following steps:

[0039] S110: Material preparation, preparing sheet metal of the predetermined size;

[0040] Preferably, the plate material is a Φ110x22mm disc;

[0041] The sheet material, by weight percentage, comprises: carbon: ≤0.07%, chromium: 15% to 17.5%, nickel: 3% to 5%, silicon: ≤1%, manganese: ≤1%, sulfur: ≤0.03%, phosphorus: ≤0.04%, copper: 3% to 5%, niobium: 0.15% to 0.45%, with the remainder being iron.

[0042] S120: Positive end face turning;

[0043] S121: Clamp one end of the sheet metal using a clamp;

[0044] Preferably, the part of the clamp that holds the disk extends 6mm from one end to the other.

[0045] S122: Drill and bore the inner hole to the predetermined size;

[0046] Preferably, the inner diameter of the drill boring tool is Φ77.8mm;

[0047] S123: Turn the outer diameter of the disc by 110 mm to the predetermined size;

[0048] Preferably, the outer diameter of the wheel disc 110 is Φ107.95mm;

[0049] S124: The upper spherical surface 120 on the vehicle reaches the predetermined size, where the outer diameter of the upper spherical surface 120 is Φ84.3 mm to Φ84.4 mm, and the height of the upper spherical surface 120 is 6.35 mm to 6.36 mm;

[0050] S130: Reverse end face turning;

[0051] S131: Clamp the disc 110 using a fixture;

[0052] S132: Turn the upper spherical surface 120 and the total length to the predetermined size, where the outer diameter of the upper spherical surface 120 is Φ84.3 mm to Φ84.4 mm, and the height of the upper spherical surface 120 is 6.35 mm to 6.36 mm;

[0053] S210: Conduct hardness, airtightness, water pressure, and thermal cycle test detections on the manufactured double - cone metal sealing ring

[0054] S211: Hardness test

[0055] Select a double - cone metal sealing ring for the hardness test. Conduct the test in accordance with GB / T4340.1 - 2009 "Metallic materials - Vickers hardness test - Part 1: Test method". During the test, clamp the specimen in a bench vice, make the axis of the indenter perpendicular to the specimen surface, rotate the load selection handwheel to HV0.01, and select a load of 0.098 N. Observe through the eyepiece, operate the cross - table, select a suitable loading point, and then start the program for Vickers hardness detection. Take Vickers hardness HV1 as the evaluation basis, and HV1≥335 is regarded as passing the inspection.

[0056] S212: Airtightness performance test

[0057] The airtightness performance test uses the airtightness test tooling for double - cone metal sealing rings and the airtightness test device for double - cone metal sealing rings. Measure the leakage rate of helium gas leaked from the double - cone metal sealing ring through a helium mass spectrometer leak detector. Take the leakage rate value as the evaluation basis, and the leakage rate ≤ 10 -6 Pa.m 3 / s is regarded as passing the inspection.

[0058] S213: Water pressure test

[0059] The water pressure test uses the water pressure test tooling for double - cone metal sealing rings and the water pressure test system for double - cone metal sealing rings. Check the sealing condition of the double - cone metal sealing ring under a maximum water pressure of 25.8 MPa. No visible leakage and a pressure drop not exceeding 0.1 MPa are regarded as passing the inspection.

[0060] S214: Thermal cycle test

[0061] The thermal cycling test uses a double-cone metal seal thermal cycling test fixture and a double-cone metal seal thermal cycling test system. Under hot conditions of temperature ≥310℃ and pressure ≥15.5MPa, the test is cycled five times, and the absence of visible leakage is considered as passing the inspection.

[0062] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor, characterized in that: The method includes the following steps: S110: Material preparation, preparing sheet metal of the predetermined size; S120: Positive end face turning; S121: Clamp one end of the sheet metal using a clamp; S122: Drill and bore the inner hole to the predetermined size; S123: Turn the outer diameter of the disc (110) to the predetermined size; S124: The spherical surface (120) on the machine is brought to the predetermined size; S130: Reverse end face turning; S131: Clamp the disk (110) with a clamp. S132: The spherical surface (120) on the vehicle and the overall length to the predetermined dimensions; S210: The manufactured double-cone metal sealing ring is tested for hardness, air tightness, water pressure, and thermal cycling. S211: Hardness Test A double-cone metal sealing ring was selected for hardness testing, and the test was conducted in accordance with GB / T4340.1-2009 "Metallic Materials - Vickers Hardness Test - Part 1: Test Method". During the test, the sample was clamped in a vise, with the indenter axis perpendicular to the sample surface. The load was selected by rotating the handwheel to HV0.01, and the load was set to 0.098 N. The test was conducted by observing through the eyepiece, operating the cross-shaped worktable, selecting an appropriate loading point, and then starting the program to perform the Vickers hardness test. The Vickers hardness HV1 was used as the evaluation criterion, and HV1 ≥ 335 was considered as passing the test. S212: Air tightness test The airtightness test uses a double-cone metal seal airtightness testing fixture and device; the leakage rate of helium leaking from the double-cone metal seal is measured using a helium mass spectrometer leak detector; the leakage rate value is used as the evaluation criterion, and a leakage rate ≤10% is acceptable. -6 Pa.m 3 / s is considered a passing inspection; S213: Hydrostatic Test The hydrostatic test uses a double-cone metal seal ring hydrostatic test fixture and a double-cone metal seal ring hydrostatic test system; the sealing condition of the double-cone metal seal ring is checked under a maximum water pressure of 25.8MPa, and the test is considered to be qualified if there is no visible leakage and the pressure drop does not exceed 0.1MPa; S214: Thermal cycling test The thermal cycling test uses a double-cone metal seal thermal cycling test fixture and a double-cone metal seal thermal cycling test system; under the hot working conditions of temperature ≥310℃ and pressure ≥15.5MPa, the test is cycled five times, and the absence of visible leakage is considered as passing the inspection.

2. The method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor according to claim 1, characterized in that: The plate material mentioned in step S110 is a disc with a diameter of 110 x 22 mm.

3. The method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor according to claim 1, characterized in that: The inner diameter of the drill boring machine in step S122 is Φ77.8mm.

4. The method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor according to claim 1, characterized in that: The outer diameter of the wheel disc (110) mentioned in step S123 is Φ107.95mm.

5. The method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor according to claim 1, characterized in that: The outer diameter of the upper spherical surface (120) is Φ84.3mm~Φ84.4mm, and the height of the upper spherical surface (120) is 6.35mm~6.36mm.

6. The method for manufacturing and inspecting a double-cone metal sealing ring for a nuclear reactor according to claim 1, characterized in that: The sheet material, by weight percentage, comprises: carbon: ≤0.07%, chromium: 15%~17.5%, nickel: 3~5%, silicon: ≤1%, manganese: ≤1%, sulfur: ≤0.03%, phosphorus: ≤0.04%, copper: 3%~5%, niobium: 0.15%~0.45%, with the remainder being iron.

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