Tooling and vulcanization method for integral vulcanization of rubber materials for lining of large equipment in nuclear power plants

Abstract

The present invention discloses a tool and vulcanization method for integral vulcanization of lining rubber materials of large-scale equipment in nuclear power plants, wherein the tool comprises a split steel plate, a supporting element, an end sealing cover plate I and an end sealing cover plate II. The method comprises: step one, sandblasting and surface treatment; step two, cleaning the sandblasted surface; step three, applying adhesive; step four, laying the semi-finished lining product; step five, loading the split steel plate and the end sealing cover plate I; step six, installing the supporting element; step seven, installing the end sealing cover plate II; step eight, transferring the equipment into a drying room, connecting the high-temperature air pipe of the drying room with the inner cavity of the pipe body; step nine, treating the equipment at 170°C; step ten, disassembling the supporting element; step eleven, trimming the rubber edge, and completing the integral compounding of the rubber lining and the inner wall of the equipment. The rubber-lined equipment obtained by the method of the present invention meets the 60-year life requirement of the nuclear power plant, can greatly reduce the maintenance cost of the nuclear power plant, and reduce the risk brought by equipment replacement.

Description

Technical Field

[0001] The invention belongs to the technical field of composite materials, and in particular relates to a tooling and a vulcanization method for integral vulcanization of lining rubber materials of large-scale equipment in nuclear power plants. Background Art

[0002] The nuclear power plant nuclear island equipment cold source equipment (SEC) has a total of 4 rows of pipes, with a total length of about 150m per row, a maximum inner diameter of 1208mm, and a minimum inner diameter of 82.8mm. The pipes are connected by flanges. The operating medium in the equipment is seawater, which is highly corrosive to carbon steel materials. Therefore, anti-corrosion materials are required for protection to prevent the inner wall of the carbon steel equipment from directly contacting seawater. At present, most carbon steel equipment uses rubber as the anti-corrosion lining material.

[0003] At present, the pre-vulcanized rubber lining cold bonding method or the natural room temperature vulcanized rubber lining method is mainly used to composite rubber and carbon steel equipment. The pre-vulcanized rubber lining cold bonding method has low bonding strength, and the natural room temperature vulcanized rubber lining method cannot guarantee the bonding strength and physical properties between the rubber lining layer and the inner wall of the equipment, and has poor stability. When affected by the seawater equipment environment, the rubber is easy to delaminate. The contact between seawater and carbon steel equipment causes local damage and defects in the carbon steel equipment, and severely causes local perforation of the equipment, resulting in a short service life of the carbon steel equipment.

[0004] The design service life of a nuclear power plant is generally 60 years. At present, in the seawater pipe lining technology, the lining usually chooses the polar rubber chloroprene rubber which is easy to bond. Neoprene is not resistant to seawater and has a maximum service life of 20 years under regular repair and treatment conditions. If the 60-year life of a nuclear power plant is to be met, the seawater pipe lined with chloroprene rubber must be replaced at least twice. Each maintenance or replacement of a large pipeline has a high safety risk, a long cycle, and is expensive (hundreds of millions of yuan each time). In addition, if a local perforation occurs in the seawater pipe lined with chloroprene rubber, it will lead to unplanned shutdown, causing hundreds of millions of economic losses. It is urgent to provide a lining process and technology that can solve the above problems once and for all, ensure the safe operation of the nuclear equipment cold source (SEC) system of a nuclear power plant, and meet the 60-year life requirements of a nuclear power plant. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an integral vulcanization method for the lining rubber material of large-scale equipment in nuclear power plants in view of the deficiencies of the above-mentioned prior art. The present invention completes the hot vulcanization compounding of the lining rubber and the carbon steel pipeline by treating the surface of the equipment, applying adhesive, laying the semi-finished product of the long-life lining, installing the split steel plate and the supporting element, and heating the whole. The obtained rubber-lined equipment meets the 60-year life requirement of the nuclear power plant, which can greatly reduce the maintenance cost of the nuclear power plant and reduce the risks brought by equipment replacement.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a tooling for integral vulcanization of lining rubber materials of large-scale equipment in nuclear power plants, the equipment comprising an inner cavity to be lined with rubber, characterized in that the tooling comprises: a split steel plate, a supporting element and an end sealing cover plate I and an end sealing cover plate II which can be respectively installed at both ends of the inner cavity to be lined with rubber, the split steel plate matches the inner cavity behind the rubber lining, a groove is provided on the split steel plate, and the supporting element comprises a supporting central axis, a supporting rod group and a latch rod.

[0007] The above-mentioned tooling for integral vulcanization of lining rubber materials of large nuclear power plant equipment is characterized in that there are multiple support rod groups, each of which includes a rod and a ring, there are multiple rods, and one end of each rod is pivotally mounted on the ring.

[0008] In addition, the present invention also provides a method for integrally vulcanizing the lining rubber material of large nuclear power plant equipment using the above-mentioned tooling for integrally vulcanizing the lining rubber material of large nuclear power plant equipment, characterized in that it comprises the following steps:

[0009] Step 1, sandblasting and surface treatment are performed on the equipment to obtain a sandblasted surface;

[0010] Step 2: Clean the sandblasted surface;

[0011] Step 3: Apply adhesive to the cleaned sandblasted surface to form an adhesive area;

[0012] Step 4: laying the semi-finished lining product in the adhesive area inside the equipment to form an inner lining area;

[0013] Step 5: Install the split-type steel plate into the inner lining area so that the split-type steel plate covers the inner lining area, and install the end cover plate I on the equipment;

[0014] Step 6, installing the support element, including: installing the support center shaft into the inner cavity to be lined with rubber, fixing one end of the support center shaft close to the end sealing cover plate I on the end sealing cover plate I, and sequentially installing the support rod group on the support center shaft from the end close to the end sealing cover plate I to the end away from the end sealing cover plate I, and the method of installing the support rod group specifically includes: sleeve the ring on the support center shaft, insert the latch rod into the support center shaft so that the ring abuts against the latch rod, and clamp the end of the rod away from the ring into the clamping groove of the petal-type steel plate to form an umbrella-shaped support;

[0015] Step 7: Install the end cover plate II, and fix the end of the support center axis close to the end cover plate II on the end cover plate II;

[0016] Step 8: transfer the equipment into a drying room, and connect the high-temperature air pipe of the drying room to the inner cavity of the equipment;

[0017] Step 9, maintaining the equipment at a temperature of 170° C. for 45 to 90 minutes;

[0018] Step 10, stop heating, open the drying room door, wait until the drying room temperature drops to ≤50°C, transport the equipment out, and disassemble the end sealing cover plate II, the latch rod, the rod, the supporting central axis, the end sealing cover plate I and the split steel plate in sequence;

[0019] Step 11: Trim the rubber edge to complete the overall bonding of the rubber lining and the inner wall of the equipment.

[0020] The above-mentioned overall vulcanization method of the lining rubber material of the large-scale equipment of the nuclear power plant is characterized in that the adhesive in step three includes a primer adhesive, a surface coating adhesive and a glue solution.

[0021] The above-mentioned method for overall vulcanization of rubber materials for lining of large-scale equipment in nuclear power plants is characterized in that the method of laying the semi-finished lining product in step 4 specifically includes: hot-refining the rubber compound to produce sheets to obtain a semi-finished lining product, splicing and laying the semi-finished lining product on the adhesive area inside the equipment, and rolling to remove air between the semi-finished lining product and the adhesive area to form an initial bonding state.

[0022] The above-mentioned integral vulcanization method of the lining rubber material of the large-scale equipment of the nuclear power plant is characterized in that the thickness of the semi-finished lining product is 3 mm to 5 mm.

[0023] The above-mentioned overall vulcanization method of the lining rubber material of the large equipment of the nuclear power plant is characterized in that the rubber compound raw material includes: 100 parts of EPDM rubber, 5 parts of zinc oxide, 30 parts of N220 carbon black, 2.5 parts of antioxidant 4010NA, 2 parts of antioxidant BLE, 1.5 parts of antioxidant AW, 3.5 parts of DCP, 0.5 parts of TAIC, 12 parts of coumarone resin, and 5 parts of melamine resin.

[0024] The above-mentioned method for integral vulcanization of rubber materials for lining of large equipment in nuclear power plants is characterized in that, in the rib-shaped support described in step six, the angle between the rod and the petal-type steel plate is 75°.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] 1. In the method of the present invention, the rib-shaped support formed by the support element matched with the split steel plate is used to provide the pressure required for rubber vulcanization, and the vulcanization is carried out by heating in a drying room. The high-temperature vulcanization allows the long-life rubber lining and adhesive to be vulcanized and composited with the inner wall of the large carbon steel pipeline. The high adhesion between the lining and the pipeline further ensures that the lining will not fall off during the long-term service of 60 years, thereby realizing long-term protection of the pipeline by the lining.

[0027] 2. In the method of the present invention, ethylene propylene diene monomer (EPDM) is selected as the raw material, and the water resistance and non-polarity of EPDM are fully utilized to effectively block seawater (polar molecular substances), avoid corrosion and perforation of carbon steel pipelines due to contact with seawater, reduce the risk of unplanned shutdown, and avoid economic losses of hundreds of millions of yuan.

[0028] 3. The large-scale pipeline manufactured by the present invention has a service life of more than 60 years, which meets the needs of the nuclear power plant throughout its entire life cycle, once and for all, and avoids the risks and costs of maintenance and replacement.

[0029] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the equipment structure on which the lining rubber material is to be installed.

[0031] Figure 2 It is a schematic diagram of the structure of the end sealing cover plate I.

[0032] Figure 3 Schematic diagram of the location of the adhesive area on the inside of the equipment.

[0033] Figure 4 Schematic diagram of the location of the inner lining area.

[0034] Figure 5 Schematic diagram of the relationship between the supporting elements and the equipment positions.

[0035] Figure 6 for Figure 5 A partial enlarged view of .

[0036] Figure 7 Schematic diagram of the rib-like support shape formed by each set of support rods. DETAILED DESCRIPTION

[0037] Example 1

[0038] This embodiment provides a method for integrally vulcanizing the rubber material of the lining of large equipment in a nuclear power plant, including using a tool for integrally vulcanizing the rubber material of the lining of large equipment in a nuclear power plant to integrally vulcanize the rubber material of the lining of the equipment, the equipment including an inner cavity to be lined with rubber, the tool including: a split steel plate 7, a support element, and an end sealing cover plate Ⅰ3 and an end sealing cover plate Ⅱ4 which can be respectively installed at both ends of the inner cavity to be lined with rubber of the equipment, the split steel plate 7 matches the inner cavity after the rubber lining, and a groove 71 is provided on the split steel plate 7; the support element includes a support center axis 81, a support rod group, and a latch rod 84. The thickness of the rubber lining is determined according to the technical provisions of the field, and the split steel plate 7 matches the shape and structure of the inner cavity to be lined with rubber after the rubber lining is completed;

[0039] In the overall vulcanization method of the lining rubber material of the large equipment of the nuclear power plant of this embodiment, the number of the support rod groups is multiple, each of the support rod groups includes a rod 82 and a ring 83, the number of the rods 82 is multiple, and one end of each of the rods 82 is pivoted on the ring 83. The multiple rods 82 can be radially spread out in a circle with the rod 82 as the center;

[0040] The end sealing cover plate I3 and the end sealing cover plate II4 are respectively detachably mounted on the two ends of the inner cavity to be lined with rubber; the equipment in this embodiment comprises a connected straight pipe section 1 and an elbow pipe section 2, as shown in FIG1 , the connected straight pipe section 1 and the elbow pipe section 2 form the inner cavity to be lined with rubber, the end sealing cover plate I3 is detachably mounted on the elbow pipe section 2 and away from the end of the straight pipe section 1, and the end sealing cover plate II4 is detachably mounted on the end of the straight pipe section 1 and away from the end of the elbow pipe section 2;

[0041] The end sealing cover plate Ⅰ3 comprises an end sealing cover plate body, a recessed platform 31 is arranged at the center of the end sealing cover plate body, a fixing bolt 32 for fixing the support center axis 81 is arranged at the center of the recessed platform 31, a plurality of end sealing bolt holes 33 are opened on the end sealing cover plate body, and the plurality of end sealing bolt holes 33 are evenly arranged around the fixing bolt 32, a through hole 34 is opened in the area between the fixing bolt 32 and the end sealing bolt hole, and the number of the through holes 34 is multiple; the structure of the end sealing cover plate Ⅰ3 is shown in the figure below: Figure 2 As shown;

[0042] The end sealing cover plate II4 and the end sealing cover plate I3 have basically the same structure; the equipment may be one of those shown in this embodiment, or the shape and size of the end sealing cover plate II4 and the end sealing cover plate I3 may also vary with the shape and size of the inner cavity to be lined with rubber of the equipment matched therewith, such as an inner cavity with different diameters;

[0043] Preferably, the straight pipe section 1 and the elbow pipe section 2 are both tubular structures with circular cross-sections, and the matching end sealing cover plates II4 and I3 are basically consistent in shape and structure, and their sizes vary with the diameters of the straight pipe section 1 and the elbow pipe section 2, which can ensure that the centers of the end sealing cover plates II4 and I3 are relatively fixed, which is beneficial for subsequent support and providing uniform vulcanization pressure.

[0044] The method comprises the following steps:

[0045] Step 1, sandblasting and surface treatment are performed on the equipment to obtain a sandblasted surface; the sandblasting includes sandblasting the inner side and end surface of the equipment; the surface treatment includes removing the oxide layer and rust layer on the surface of the carbon steel;

[0046] Step 2: Clean the sandblasted surface: Use gasoline to clean the surface after sandblasting and surface treatment to remove dust and oil stains;

[0047] Step 3: Apply adhesive to the cleaned sandblasted surface to form an adhesive area 5; the adhesive area 5 and the equipment position are shown in the figure below: Figure 3 As shown; the method of applying the adhesive specifically comprises: first brushing the primer adhesive on the cleaned sandblasted surface, brushing the adhesive twice, and brushing the top coating adhesive after the solvent evaporates and dries, brushing the adhesive twice, applying the glue liquid, and drying;

[0048] The primer adhesive is Chemlock 607, the top coating adhesive is Chemlock 238, and the adhesive liquid is prepared from lining rubber compound and solvent benzene;

[0049] Step 4: Lay the semi-finished lining product on the adhesive area 5 inside the equipment to form an inner lining area 6; the position of the inner lining area 6 is shown in the figure below: Figure 4 As shown; the method for laying the semi-finished lining specifically comprises: hot-refining the lining with rubber compound, producing sheets according to a preset sheet thickness to obtain a semi-finished lining, splicing and laying the semi-finished lining on the adhesive area 5 inside the equipment, rolling to remove air between the semi-finished lining and the adhesive area 5, and forming an initial bonding state; the thickness of the semi-finished lining is 3mm to 5mm;

[0050] The raw materials of rubber compound for lining include: 100 parts of EPDM rubber, 5 parts of zinc oxide, 30 parts of super wear-resistant carbon black N220 carbon black, 2.5 parts of antioxidant 4010NA, 2 parts of antioxidant BLE, 1.5 parts of antioxidant AW, 3.5 parts of DCP, 0.5 parts of TAIC, 12 parts of coumarone resin, and 5 parts of melamine resin;

[0051] The EPDM rubber is a copolymer of ethylene, propylene and dicyclopentadiene DCPD, with an ethylene content of 50%, a propylene content of 44% and a DCPD content of 6%;

[0052] Step 5: Install the split steel plate 7 into the inner lining area 6 so that the split steel plate 7 covers the inner lining area 6, and connect and fix the end cover plate Ⅰ3 to the elbow pipe section 2; the connection and fixation can be carried out by flanges and bolts; -

[0053] Step 6, installing the support element, including: installing the support center shaft 81 into the inner cavity to be lined with rubber, fixing the end of the support center shaft 81 close to the end sealing cover plate Ⅰ3 on the end sealing cover plate Ⅰ3, and the other end of the support center shaft 81 can be kept flat by a bracket, so that the support center shaft 81 is kept coincident with the central axis of the inner cavity to be lined with rubber; from the end close to the end sealing cover plate Ⅰ3 to the end away from the end sealing cover plate Ⅰ3, the support rod group is sequentially installed on the support center shaft 81, and the method of installing the support rod group specifically includes: fixing the ring 83 Sleeved on the support center axis 81, the latch rod 84 is inserted into the support center axis 81 so that the ring 83 abuts against the latch rod 84, and the end of the rod 82 away from the ring 83 is engaged in the slot 71 of the split steel plate 7 to form an umbrella rib-shaped support; the umbrella rib-shaped support formed by the support rod group applies pressure to the inner lining area 6, and gives the lining a uniform physical force in subsequent processing, which serves as the lining vulcanization pressure; the support center axis 81 is provided with a latch rod hole for inserting the latch rod 84, and the number of the latch rod holes is multiple, and the multiple latch rod holes are evenly spaced along the axis of the support center axis 81, and the latch rod 84 can be installed into the latch rod hole by using a mechanical arm;

[0054] In the rib-shaped support, the rod 82 and the split-flap steel plate 7 form an angle of 75°, which not only realizes pressurization, but also facilitates the disassembly and assembly of components.

[0055] Step 7: Install the end sealing cover plate II4, fix the end of the support center axis 81 close to the end sealing cover plate II4 on the end sealing cover plate II4; remove the bracket, and fix the end sealing cover plate II4 to the straight pipe section 1 with a nut; the position relationship between the support element and the equipment is as follows: Figure 5 As shown, the schematic diagram of the rib-shaped support structure is shown in Figures 6 and 7;

[0056] Step 8, transfer the equipment into the drying room, connect the high-temperature air pipe of the drying room with the inner cavity of the equipment; connect the through hole 34 opened on the end sealing cover plate Ⅰ3 or the through hole opened on the end sealing cover plate Ⅱ4 with the high-temperature air pipe of the drying room, so that heat is loaded on the inside and outside of the equipment at the same time, thereby improving the vulcanization efficiency;

[0057] Step 9, keep the equipment at a temperature of 170°C for 45 to 90 minutes; when the thickness of the semi-finished lining product is 3 mm, the heat-drying time is 45 minutes, and when the thickness of the semi-finished lining product is 5 mm, the heat-drying time is 90 minutes;

[0058] Step 10, stop heating, open the drying room door, wait until the drying room temperature drops to ≤50°C, transport the equipment out, and disassemble the end sealing cover plate II4, the latch rod 84, the rod 82, the supporting central axis 81, the end sealing cover plate I3 and the split steel plate 7 in sequence;

[0059] Step 11: Trim the rubber edge, complete the rubber lining, and complete the overall bonding of the rubber lining and the inner wall of the equipment.

[0060] Performance evaluation:

[0061] After the inner lining rubber is assembled according to the method of the embodiment, samples are taken from the rubber lining equipment and ground into standard samples, which are tested simultaneously with the standard samples of the rubber compound raw materials used for the corresponding lining. The standards and test results of the test method are shown in Tables 1 and 2.

[0062] Table 1 Performance testing methods and standards

[0063] Serial number Test items Implementation Standards 1 Tensile Strength GB / T 528-2009 2 Elongation at break GB / T 528-2009 3 hardness GB / T 531.1-2008 4 Adhesion strength GB / T 7760-2003

[0064] Table 2 Test results of aging-resistant rubber materials for rubber lining equipment in nuclear power plants

[0065]

[0066]

[0067] It can be seen from Table 2 that the rubber lining performance of the rubber lining equipment completed by the method of the present invention meets the technical requirements of the rubber lining of large equipment in nuclear power plants.

[0068] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment according to the technical essence of the invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A tool for integral vulcanization of rubber materials for lining of large equipment in nuclear power plants, the equipment comprising an inner cavity to be lined with rubber, characterized in that: The tooling comprises: a split-type steel plate (7), a supporting element, and an end sealing cover plate I (3) and an end sealing cover plate II (4) which can be respectively installed at the two ends of the inner cavity to be lined with rubber, the split-type steel plate (7) matches the inner cavity after the rubber lining, the split-type steel plate (7) is provided with a groove (71), and the supporting element comprises a supporting central axis (81), a supporting rod group and a latch rod (84); the number of the supporting rod groups is plural, and each of the supporting rod groups comprises a rod member (82) and a ring member (83), the number of the rod members (82) is plural, and one end of each of the rod members (82) is pivotally mounted on the ring member (83).

2. A method for integrally vulcanizing the lining rubber material of large nuclear power plant equipment using the tooling for integrally vulcanizing the lining rubber material of large nuclear power plant equipment as claimed in claim 1, characterized in that: The following steps are involved: Step 1, sandblasting and surface treatment are performed on the equipment to obtain a sandblasted surface; Step 2: Clean the sandblasted surface; Step 3: applying adhesive on the cleaned sandblasted surface to form an adhesive area (5); Step 4: laying the semi-finished lining product on the adhesive area (5) inside the equipment to form an inner lining area (6); Step 5: Install the split steel plate (7) into the inner lining area (6) so that the split steel plate (7) covers the inner lining area (6), and install the end cover plate I (3) on the equipment; Step 6, installing the support element, including: installing the support center axis (81) into the inner cavity to be lined with rubber, fixing one end of the support center axis (81) close to the end sealing cover plate I (3) on the end sealing cover plate I (3), and sequentially installing the support rod group on the support center axis (81) from the end close to the end sealing cover plate I (3) to the end away from the end sealing cover plate I (3), wherein the method for installing the support rod group specifically includes: sleeve the ring member (83) on the support center axis (81), insert the latch rod (84) into the support center axis (81) so that the ring member (83) abuts against the latch rod (84), and clamp the end of the rod member (82) away from the ring member (83) into the groove (71) of the split steel plate (7) to form an umbrella rib-shaped support; Step 7: Install the end sealing cover plate II (4), and fix the end of the supporting central shaft (81) close to the end sealing cover plate II (4) on the end sealing cover plate II (4); Step 8: transfer the equipment into a drying room, and connect the high-temperature air pipe of the drying room to the inner cavity of the equipment; Step 9, maintaining the equipment at a temperature of 170° C. for 45 to 90 minutes; Step 10: stop heating, open the drying room door, wait until the drying room temperature drops to ≤50°C, transport the equipment out, and disassemble the end sealing cover plate II (4), the latch rod (84), the rod (82), the supporting central shaft (81), the end sealing cover plate I (3) and the split steel plate (7) in sequence; Step 11: Trim the rubber edge to complete the overall bonding of the rubber lining and the inner wall of the equipment.

3. The overall vulcanization method of the lining rubber material of large-scale equipment in nuclear power plants according to claim 2, characterized in that: The adhesive in step three includes a primer adhesive, a surface adhesive and a glue solution.

4. The overall vulcanization method of the lining rubber material of large-scale equipment in nuclear power plants according to claim 2, characterized in that: Step 4: The method for laying the semi-finished lining specifically comprises: hot-refining the rubber compound to produce sheets to obtain the semi-finished lining, splicing and laying the semi-finished lining on the adhesive area (5) inside the equipment, and rolling to remove air between the semi-finished lining and the adhesive area (5) to form an initial bonding state.

5. The integral vulcanization method of the lining rubber material of large-scale equipment in nuclear power plants according to claim 4, characterized in that: The thickness of the semi-finished lining product is 3 mm to 5 mm.

6. The integral vulcanization method of the lining rubber material of large-scale equipment in nuclear power plants according to claim 4, characterized in that: The rubber compound raw materials include: 100 parts of EPDM rubber, 5 parts of zinc oxide, 30 parts of N220 carbon black, 2.5 parts of antioxidant 4010NA, 2 parts of antioxidant BLE, 1.5 parts of antioxidant AW, 3.5 parts of DCP, 0.5 parts of TAIC, 12 parts of coumarone resin and 5 parts of melamine resin.

7. The integral vulcanization method of the lining rubber material of large-scale equipment in nuclear power plants according to claim 2, characterized in that: In the rib-shaped support described in step six, the angle between the rod (82) and the split-type steel plate (7) is 75°.

Images