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I. Project Overview: A 10,000 m³ vertical cylindrical arch-type welded steel storage tank, with a tank diameter of 30 m and a total tank wall height of 14.2 m. The thickness of the tank bottom plate is 6 mm and 10 mm respectively, the thickness of the wall plates at each layer ranges from 8 mm to 20 mm, the thickness of the top plate is 6 mm, and the total weight of the tank is 250 t. The installation of each layer of shell plates and the tank roof is carried out using the hydraulic lifting equipment upside-down installation method. II. Construction Preparation 1. Materials for the project and those for construction measures (1) Main materials for the project The main materials used in this project include: mid-span plate at the bottom of the tank, δ=6mm, 36t ； Side panel δ=10mm, 14t ； Tank wall plates δ=8~20mm, 160t ； Tank top plate δ=6mm, 40t. (2) Materials for the measures: The main materials used for these measures include those for the formwork of the top and side panels, materials for expansion rings, as well as materials for support pipes and curved clamps. That is, materials such as steel plates, pipes, and sleepers. 2. Main Equipment The main construction equipment includes: truck cranes, hydraulic lifters, welding machines, hydraulic pumps, gas welding equipment, etc. 3. Preparation and conditions for on-site work: (1) Re-measure and inspect the elevation, slope, and diameter of the storage tank foundation, and carry out the acceptance procedures for intermediate handover. (2) Re-measure the geometric dimensions of semi-finished storage tanks and steel profile components, verify the material certificates of quality, and simultaneously carry out the acceptance procedures for the interim handover. (3) The crane access roads at the construction site are unobstructed, and all kinds of jigs and materials for safety measures are readily available. (4) The elevator, hydraulic pump, hydraulic pipes, hydraulic oil, and power cables are all fully equipped. III. Labor Organization: For the installation of the 10,000 m³ storage tank, 12 riveters, 12 welders, 4 grinders, 2 gas welders, 3 signal workers, 2 maintenance electricians, and 1 fitter are required. IV. Main Construction Techniques 1. Construction Procedure The main procedure for installing storage tanks using hydraulic lifting equipment is to first carry out the weldment of the tank bottom plate ； Then, perform the assembly and welding of the top-layer wall panels and top plate ； Proceed with the installation of the lifting equipment ； Finally, the assembly and welding of the second-layer to bottom-layer wall panels are carried out in sequence. 2. Welding of the base plates: Once the foundation has been inspected and approved, the laying of the base plates can proceed. The welding procedure for the bottom plate is as follows: weld the short seams first, then the long seams; the turtle-shell joints between the side plates and the mid-span plates are to be welded after the bottom wall plates are installed. 3. Assembly and welding of the top plate: First, carry out the assembly and welding of the top-layer wall panels and edging angle steels. Then, assemble the top plate at the tank bottom, install the jigs, and lower the hydraulic lifting equipment and expansion rings into the tank. Once everything is properly installed, proceed with the assembly and welding of the top plate. 4. Assembly and welding of wall panels: A hydraulic jack is used to lift the already assembled top-layer wall panels and top plate. Meanwhile, the assembly of the second-layer wall panels and the welding of their longitudinal seams are carried out. Subsequently, spot welding is performed for the circumferential seams between the two layers of wall panels, followed by welding of the inner and outer welds. Once the welds of the wall panels after welding have passed non-destructive testing, the expansion rings inside the tank can be loosened, the lifting device can be placed beneath the second layer of wall panels, and preparation can begin for assembling the third layer of wall panels. Following the aforementioned procedures and methods, proceed until the welding of the wall panels at each of the following layers is completed. 5. Welding of the bottom wall panels to the bottom plate: First, weld the lower wall panels to the bottom plate, and then weld the side panels to the middle plates. 6. Installation of accessories and tank testing: First, all the manholes, material inlet pipes, inspection holes, ventilation holes, light-transmitting holes, connection pipe holes, ladders on the tank, as well as all welded components attached to the tank, are welded together. Finally, the tank is subjected to a water filling test and a airtightness test. V. Quality Standards 1. Mainly applicable construction specifications (1) “Specifications for Construction and Acceptance of Cylindrical Steel Welded Storage Tanks”. (2) “Code for Construction and Acceptance of Welding Works for Field Equipment and Industrial Piping”. 2. Key points for quality inspection: (1) The local unevenness after welding of the base plate shall not exceed 50 mm. (2) The out-of-roundness of the wall panel shall not exceed 20 mm. (3) The misalignment of the wall panels shall not exceed 3 mm. (4) The local unevenness of the top plate after welding shall not exceed 30 mm. (5) The verticality of the tank wall shall not exceed H/1000. VI. Precautions 1. When stacking, transporting, and lifting wall panels and roof panels, measures should be taken to prevent deformation. 2. Hydraulic lifters and related equipment must be inspected before use, and they require a dedicated operator. 3. Before lifting the tank, carefully check whether the clamping plates on the expansion ring are firmly welded. 4. Hitting the tank body is strictly prohibited during the lifting process.