Method for manufacturing and inspecting bowl-shaped metal sealing ring of nuclear reactor

Abstract

The invention relates to the technical field of sealing elements, and particularly discloses a method for manufacturing and inspecting a bowl-shaped metal sealing ring of a nuclear reactor. The method comprises the following operation steps that S110, material preparation is conducted, specifically, a plate with the preset size is prepared; s120, cutting is conducted, specifically, the plate is cut into a circular ring with the preset size; s130, compression molding is conducted, specifically, a mold is used, and the circular ring cut and formed in the step S120 is molded into a bowl shape; s140, the bowl-shaped sealing ring formed through compression molding is polished to the preset roughness; and S210, carrying out compression resilience performance, hardness, air tightness, water pressure and thermal cycle test detection on the manufactured bowl-shaped metal sealing ring. The performance of the bowl-shaped metal sealing ring can be effectively verified through evaluation standards of hardness, air tightness, water pressure and thermal cycle tests while the manufacturing process is improved, frequent replacement caused by the quality problem of the bowl-shaped metal sealing ring is avoided, and the production efficiency of a nuclear power plant is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of sealing parts, and in particular relates to a method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor. Background Art

[0002] Thermocouple mechanical seals for nuclear reactor pressure vessels are important equipment in the main system of pressurized water reactor nuclear power units. They are the primary pressure boundary, and their main function is to maintain the integrity of the primary pressure boundary. During the operation of the nuclear reactor, the pressure vessel bears the effects of high temperature (≥310°C), high pressure (≥15.5MPa), and water flow impact of the primary boric acid water. Thermocouple mechanical seals mainly include: bowl-shaped metal seals, double-cone metal seals, male flanges, clamps and other mechanical parts. Among them, the bowl-shaped metal seal faces high temperature, high pressure and large vibration conditions, which makes its sealing effect decay significantly, and it is difficult to meet the normal use requirements of the thermocouple mechanical seals for nuclear reactor pressure vessels. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor in view of the above-mentioned deficiencies in the prior art. By improving the manufacturing process and strictly inspecting the defects of the finished product, the finished product can meet the working conditions.

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

[0005] S110: material preparation, preparing sheets of predetermined size;

[0006] S120: cutting, cutting the sheet material into a ring of a predetermined size;

[0007] S130: molding, using a mold, molding the ring cut and formed in step S120 into a bowl shape;

[0008] S140: polishing the molded bowl-shaped sealing ring to a predetermined roughness;

[0009] S210: Conduct compression and resilience performance, hardness, air tightness, water pressure and thermal cycle tests on the manufactured bowl-shaped metal sealing ring;

[0010] S211: Select bowl-shaped metal sealing rings for compression and rebound performance tests under different pressure loads. The test loads are 20KN, 30KN, 40KN and 50KN respectively. The compression and rebound under 40KN pressure load are used as the evaluation basis. The compression ≥2.00mm and the rebound ≥0.20mm are considered qualified.

[0011] S212: Hardness test

[0012] Select a bowl-shaped metal seal ring for hardness test, refer to GB / T4340.1-2009 "Metallic Materials Vickers Hardness Test Part 1: Test Method" for test; during the test, clamp the sample on the bench vise, make the axis of the indenter perpendicular to the sample surface, rotate the load selection handwheel to HV0.01, and select a load of 0.098N. Observe through the eyepiece, operate the cross workbench, select a suitable loading point, and then start the program to perform Vickers hardness test; use Vickers hardness HV1 as the evaluation basis, HV1 ≥ 156 is considered qualified;

[0013] S213: Airtightness test

[0014] The airtight performance test uses a special bowl-shaped metal sealing ring airtightness test tool and a bowl-shaped metal sealing ring airtightness test device; under a pressure load of 40KN, the leakage rate of helium from the bowl-shaped metal sealing ring is measured by a helium mass spectrometer leak detector; the leakage rate value is used as the evaluation basis, and a leakage rate ≤10-10Pa.m3 / s is considered to be qualified;

[0015] S240: Hydrostatic test

[0016] The water pressure test uses a special bowl-shaped metal sealing ring water pressure test tool and bowl-shaped metal sealing ring water pressure test system; the sealing condition of the bowl-shaped metal sealing ring is checked under a maximum water pressure of 25.8MPa, and it is considered qualified if there is no visible leakage and the pressure drop does not exceed 0.1MPa;

[0017] S250: Thermal Cycle Test

[0018] The thermal cycle test uses a special bowl-shaped metal sealing ring thermal cycle test tooling and a bowl-shaped metal sealing ring thermal cycle test system; the test is carried out under hot working conditions of temperature ≥310℃ and pressure ≥15.5MPa, and the test is considered qualified if there is no visible leakage.

[0019] In step S110, the sheet material is a disc with a size of Φ80x0.8mm.

[0020] The sheet material comprises, by mass percentage, carbon: ≤0.08%, chromium: 17%-19%, nickel: 9-12%, silicon: ≤1%, manganese: ≤2%, sulfur: ≤0.03%, phosphorus: ≤0.045%, niobium: 0.8%-1%, and the rest of the material is iron.

[0021] In step S120, the inner diameter of the ring is Φ54 mm, and the outer diameter is Φ68 mm.

[0022] In step S120, the sheet material is cut by laser cutting.

[0023] In step S140, the roughness of the inner surface and the outer surface of the side of the formed bowl-shaped sealing ring is Ra0.4, and the roughness of the two end surfaces of the side is Ra1.6.

[0024] In step S140, the polishing tool for the bowl-shaped sealing ring is felt silk.

[0025] The outer diameter of the upper bottom surface of the bowl-shaped metal sealing ring is Φ66-Φ66.2mm, the inner diameter of the lower bottom surface is Φ53.5-Φ53.7mm, and the busbar length is 6.95mm-7.05mm.

[0026] The remarkable effect of the present invention is that the manufacturing and inspection method of a nuclear reactor bowl-shaped metal sealing ring described in the present invention can effectively verify the performance of the bowl-shaped metal sealing ring by improving the manufacturing process through the evaluation standards of hardness, airtightness, water pressure, and thermal cycle tests, thereby avoiding frequent replacement of the bowl-shaped metal sealing ring due to quality problems and improving the production efficiency of nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic flow chart of a method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to the present invention;

[0028] Figure 2 It is a schematic diagram of the structure of a bowl-shaped metal sealing ring;

[0029] Figure 3 It is a structural schematic diagram of a mold used in a method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to the present invention;

[0030] In the figure: 1. Pressing block; 2. Male flange; 3. Female flange; 4. Mold core. DETAILED DESCRIPTION

[0031] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solutions in the invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of the present invention.

[0032] In the description of the present invention, it should be noted that the directions or positional relationships indicated by “upper” and the like are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience and simplification of the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0033] In the description of the present invention, the terms “first” and “second” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connect", "set", "install", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0035] like Figure 2 As shown, the bowl-shaped metal sealing ring made by the method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor described in the present invention is in the shape of a hollow truncated cone as a whole, and the angle θ formed by the generatrix of the truncated cone and the lower bottom surface is 32° to 33°.

[0036] like Figure 3 As shown, the mold involved in the manufacturing and inspection method of a nuclear reactor bowl-shaped metal sealing ring of the present invention includes a pressing block 1, a male flange 2, a female flange 3, and a mold core 4. The female flange 3 is sleeved on the outside of the mold core 4 and is stationary on the hydraulic press platform. The raw material ring is placed flat on the upper end surface of the mold core 4. The male flange 2 and the pressing block 1 are sleeved on the outside of the mold core 4 in sequence and placed on the upper end surface of the raw material ring. The hydraulic press push rod is operated to move from top to bottom, and its pressure acts on the upper end surface of the pressing block 1 and causes the pressing block 1 and the male flange 2 to move downward until the pressing block 1 and the male flange 2 stop. After retracting the hydraulic press push rod, the pressing block 1 and the male flange 2 are removed, and a bowl-shaped metal sealing ring can be obtained between the male flange 2 and the female flange 3.

[0037] like Figure 1 As shown, the present invention provides a method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor, the method comprising the following steps:

[0038] S110: material preparation, preparing sheets of predetermined size;

[0039] Preferably, the sheet material is a disc of Φ80x0.8mm;

[0040] The sheet material, in terms of mass percentage, comprises: carbon: ≤0.08%, chromium: 17% to 19%, nickel: 9 to 12%, silicon: ≤1%, manganese: ≤2%, sulfur: ≤0.03%, phosphorus: ≤0.045%, niobium: 0.8% to 1%, and the remaining material is iron;

[0041] S120: cutting, cutting the sheet material into a ring of a predetermined size;

[0042] Preferably, the inner diameter of the ring is Φ54 mm and the outer diameter is Φ68 mm;

[0043] Further preferably, the sheet material is cut by laser cutting;

[0044] S130: Compression molding, use as Figure 3 The mold shown, the ring cut and formed in the molding step S120 is molded into a bowl shape;

[0045] S140: polishing the molded bowl-shaped sealing ring to a predetermined roughness;

[0046] As an embodiment, the roughness of the inner and outer surfaces of the side surface is Ra0.4, and the roughness of the two end surfaces of the side surface is Ra1.6;

[0047] Preferably, felt silk is used for polishing;

[0048] The final formed bowl-shaped metal sealing ring has an outer diameter of the upper bottom surface of Φ66-Φ66.2mm, an inner diameter of the lower bottom surface of Φ53.5-Φ53.7mm, and a busbar length of 6.95mm-7.05mm;

[0049] S210: Conduct compression and resilience performance, hardness, air tightness, water pressure and thermal cycle tests on the manufactured bowl-shaped metal sealing ring;

[0050] S211: Select bowl-shaped metal sealing rings for compression and rebound performance tests under different pressure loads. The test loads are 20KN, 30KN, 40KN and 50KN respectively. The compression and rebound under 40KN pressure load are used as the evaluation basis. The compression ≥2.00mm and the rebound ≥0.20mm are considered qualified.

[0051] S212: Hardness test

[0052] Select a bowl-shaped metal seal ring for hardness test, refer to GB / T4340.1-2009 "Metallic Materials Vickers Hardness Test Part 1: Test Method" for test; during the test, clamp the sample on the bench vise, make the axis of the indenter perpendicular to the sample surface, rotate the load selection handwheel to HV0.01, and select a load of 0.098N. Observe through the eyepiece, operate the cross workbench, select a suitable loading point, and then start the program to perform Vickers hardness test; use Vickers hardness HV1 as the evaluation basis, HV1 ≥ 156 is considered qualified;

[0053] S213: Airtightness test

[0054] The airtight performance test uses a special bowl-shaped metal sealing ring airtightness test tool and a bowl-shaped metal sealing ring airtightness test device; under a pressure load of 40KN, the leakage rate of helium from the bowl-shaped metal sealing 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 -10 Pa.m 3 / s is deemed to have passed the inspection;

[0055] S240: Hydrostatic test

[0056] The water pressure test uses a special bowl-shaped metal sealing ring water pressure test tool and bowl-shaped metal sealing ring water pressure test system; the sealing condition of the bowl-shaped metal sealing ring is checked under a maximum water pressure of 25.8MPa, and it is considered qualified if there is no visible leakage and the pressure drop does not exceed 0.1MPa;

[0057] S250: Thermal Cycle Test

[0058] The thermal cycle test uses a special bowl-shaped metal sealing ring thermal cycle test tooling and a bowl-shaped metal sealing ring thermal cycle test system; the test is carried out under hot working conditions of temperature ≥310℃ and pressure ≥15.5MPa, and the test is considered qualified if there is no visible leakage.

[0059] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor, characterized in that: The method comprises the following steps: S110: material preparation, preparing sheets of predetermined size; S120: cutting, cutting the sheet material into a ring of a predetermined size; S130: molding, using a mold, molding the ring cut and formed in step S120 into a bowl shape; S140: polishing the molded bowl-shaped sealing ring to a predetermined roughness; S210: Conduct compression and resilience performance, hardness, air tightness, water pressure and thermal cycle tests on the manufactured bowl-shaped metal sealing ring; S211: Select a bowl-shaped metal sealing ring to conduct compression rebound performance tests under different pressure loads. The test loads are 20KN, 30KN, 40KN, and 50KN respectively; The compression and rebound under 40KN pressure load are used as the evaluation basis. Compression ≥ 2.00mm and rebound ≥ 0.20mm are considered qualified. S212: Hardness test Select a bowl-shaped metal seal ring for hardness test, refer to GB / T4340.1-2009 "Metallic Materials Vickers Hardness Test Part 1: Test Method" for test; during the test, clamp the sample on the bench vise, make the axis of the indenter perpendicular to the sample surface, rotate the load selection handwheel to HV0.01, and select a load of 0.098N. Observe through the eyepiece, operate the cross workbench, select a suitable loading point, and then start the program to perform Vickers hardness test; use Vickers hardness HV1 as the evaluation basis, HV1 ≥ 156 is considered qualified; S213: Airtightness test The airtightness test uses a special bowl-shaped metal sealing ring airtightness test tool and a bowl-shaped metal sealing ring airtightness test device; Under a pressure load of 40KN, the helium leakage rate of the bowl-shaped metal sealing ring is measured by a helium mass spectrometer leak detector; the leakage rate value is used as the evaluation basis, and the leakage rate is ≤10 -10 Pa.m 3 / s is deemed to have passed the inspection; S240: Hydrostatic test The water pressure test uses a special bowl-shaped metal sealing ring water pressure test tool and bowl-shaped metal sealing ring water pressure test system; the sealing condition of the bowl-shaped metal sealing ring is checked under a maximum water pressure of 25.8MPa, and it is considered qualified if there is no visible leakage and the pressure drop does not exceed 0.1MPa; S250: Thermal Cycle Test The thermal cycle test uses a special bowl-shaped metal sealing ring thermal cycle test tooling and a bowl-shaped metal sealing ring thermal cycle test system; the test is carried out under hot working conditions of temperature ≥310℃ and pressure ≥15.5MPa, and the test is considered qualified if there is no visible leakage.

2. A method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to claim 1, characterized in that: In step S110, the sheet material is a disc with a size of Φ80x0.8mm.

3. The method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to claim 1, characterized in that: The sheet material comprises, by mass percentage, carbon: ≤0.08%, chromium: 17%-19%, nickel: 9-12%, silicon: ≤1%, manganese: ≤2%, sulfur: ≤0.03%, phosphorus: ≤0.045%, niobium: 0.8%-1%, and the rest of the material is iron.

4. A method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to claim 1, characterized in that: In step S120, the inner diameter of the ring is Φ54 mm, and the outer diameter is Φ68 mm.

5. The method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to claim 1, characterized in that: In step S120, the sheet material is cut by laser cutting.

6. A method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to claim 1, characterized in that: In step S140, the roughness of the inner surface and the outer surface of the side of the formed bowl-shaped sealing ring is Ra0.4, and the roughness of the two end surfaces of the side is Ra1.

6.

7. A method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to claim 1, characterized in that: In step S140, the polishing tool for the bowl-shaped sealing ring is felt silk.

8. The method for manufacturing and inspecting a bowl-shaped metal sealing ring for a nuclear reactor according to claim 1, characterized in that: The outer diameter of the upper bottom surface of the bowl-shaped metal sealing ring is Φ66-Φ66.2mm, the inner diameter of the lower bottom surface is Φ53.5-Φ53.7mm, and the busbar length is 6.95mm-7.05mm.

Images