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The manufacturing process of the inner tank: 1. First assemble the three cylinder sections and weld them with a long-arm submerged arc welding machine. 2. Use the cylinder assembly tooling assembly to align the cylinder sections, and fix the outer welding spots manually. 3. The inner side is submerged arc welded, the outer side is gouged with carbon arc gouging and polished to shine with a grinding wheel, and the outer side is submerged arc welded. 4. After welding, 3 to 4 circumferential seam welding support molds can be removed, but the circumferential seam welding support molds at both ends must be retained. 5. In the future, each group can weld one cylinder after pairing, or two cylinders can be welded after pairing together, provided that long-arm submerged arc welding can be welded. 6. By analogy, the final tube is said to maintain 6 circumferential seam welding support molds. 7. Surface grinding is performed on all welds, and 20% of the welds pass the radiographic flaw detection level III. 8. After passing the flaw detection, assemble the reinforcing ring, solidify the mixed gas shielded welding joints, and perform intermittent welding with 100% welding and 80% welding time. 9. Mark the cylinder and open the nozzle. The opening position should be away from the welding seam by no less than 100mm. Use a grinding wheel and a grinding head to polish the groove. Assemble the explosion-proof device nozzle and the perlite filling tooling. The hand arc welding joints are solid, and the welding wire is H10Mn2. Post-weld coloring inspection of welds. 10. After the surface of the inner cylinder is degreased, the transition nozzle is sealed from the outside with self-adhesive tape, and both ends of the cylinder are sealed with plastic sheets until the head is assembled. The production process of the outer cylinder of the storage tank: 1. The outer cylinder should be made of wide and long plates as much as possible to ensure the length of the weld seam. 2. Before cutting the cylinder plate, the diagonal tolerance of the plate must be confirmed. If the deviation is too large, the edge of the plate should be cut twice. 3. Barrel plate blanking, cutting, edge planing (beveling), and bevel processing (blunt edge 6mm, 30-degree bevel). The longitudinal joints of the cylinder should be internally grooved. 4. The cylinder plate is assembled and assembled, the manual welding points are solidly welded, the groove surface is submerged arc welded, the back is carbon arc gouged and polished to a metallic luster with a grinding wheel, and the back is submerged arc welded. 5. Use tooling to guide both ends of the cylinder before rolling, and confirm the size according to the sample. 6. Plate rolling machine roll body. A 4-claw sling must be used when lifting the flat plate. When the cylinder is rolled more than half, the sling should be used to hold the cylinder to prevent the diameter of the cylinder from changing or collapsing. 7. The molding size must be confirmed with a sample when rolling the plate. 8. After the cylinder is rolled and qualified, the manual soldering joints are assembled and solidified. 9. Install the outer cylinder longitudinal seam support mold, and the installation position of the support mold should be able to be welded. 10. Submerged arc welding is used to weld the longitudinal seam of the barrel section. The back side is gouged with carbon arc gouging and polished to a metallic luster with a grinding wheel, and the back side is submerged arc welded. 11. The outer cylinder circumferential seam welding support moldings are installed at both ends of the cylinder, and the screw is used to adjust the cylinder to achieve optimal roundness. Remove the longitudinal weld support tire. 12. Assembling the tank cylinder and head: 1) The right head is assembled with the cylinder, and the outer hand arc welding points are solid. The inner side is welded by hand arc welding, and the outer side is gouged with carbon arc gouging and polished to a metallic luster with a grinding wheel. External submerged arc welding. 2) The right side head and cylinder welds pass the Level II radiographic inspection, 3) Assemble the tube nozzle and transition joint. The argon arc welding joint is solid and the argon arc welding is welding. 4) Clean the interior and perform partial degreasing treatment. 5) Assemble the left head and cylinder. Use argon arc welding to solidify the joints, use argon arc welding to perform bottom seal welding, and then use argon arc welding to weld one layer. Then use submerged arc welding with low current to weld one layer. Use normal current submerged arc welding on the surface. 6) The welds between the left head and the cylinder pass the level II radiographic inspection. 7) Assemble the internal piping with the cylinder. 8) Assemble the welding adsorption device. The low-temperature automatic regulating valve opens and the gas is discharged to the BOG heater or low-pressure torch to balance the pressure in the tank ； When the gas phase pressure in the tank drops to 15KPa (can be adjusted according to the process package). The low temperature regulating valve is closed. To maintain the tank pressure within a safe range. Air supply system. ◆If the gas phase pressure in the storage tank drops to 5KPa, the low-temperature automatic regulating valve on the gas supply line opens. When the storage tank pressure rises to 10KPa, the gas supply stops (the specifics can be fine-tuned according to the liquefaction process package) to keep the storage tank pressure operating within a safe pressure range. EAG vent line, ◆When the gas phase pressure in the storage tank is higher than 25KPa, the vent regulating valve opens. The gas low-pressure flare system inside the storage tank or the tank top discharge main pipe, storage tank safety, ◆LNG storage tank top discharge line is equipped with a nitrogen seal in front of the flame arrester. Generally, multiple vacuum tanks are used for centralized storage. (2) Mother tank. The inner tank of the mother tank is multiple low-temperature resistant stainless steel pressure vessels, and the outer tank is a large carbon steel container covering the multiple inner tanks. The space between the inner and outer tanks is also filled with insulating material, and dry nitrogen is passed through the interlayer. In order to prevent moist air, the inner tank of the mother-child tank is manufactured in the factory, pressure tested and shipped to the site. The outer tank is installed on site. (3) Normal pressure tank. The structure of the normal pressure tank includes a bimetal tank, and the outer tank adopts a prestressed concrete structure. ； There are above ground tanks. There are also underground tanks. Those below 20,000m3 are mostly bimetallic tanks. Both the inner and outer tanks of the normal pressure tank are installed and manufactured on site. The production cycle is longer. There are three main classifications of LNG storage tank shapes. The following are the places where each shape is mainly used. (1) LNG spherical storage tank LNG spherical storage tank is mainly used in civil gas gasification stations, LNG vehicle filling stations, etc. How much does a Suzhou vacuum cryogenic liquid storage tank cost? It has stable performance