Installation technology of dry gas holder

1.1 Project overview
Twenty-thousand cubic meters of Wiggins dry-type gas tank is used to store low pressure gas in oil refining enterprises. Its structure is composed of vertical edge, tank bottom, tank wall, tank top, T-rail and T-rail rack, piston bottom plate and piston column, leveling device, sealing device and other accessories. The cabinet specification is @ 34377x4.5 (6) x28500, and the total weight of the gas tank is 574698kg (excluding the weight of the piston concrete dam).
1.2 1: Process characteristics
The gas holder has complex structure, large construction workload and long construction period; There are many assembly rings with high accuracy requirements: there are many welds on thin plates and section steels, and the welding deformation is difficult to control; There are many lifting operations and it is difficult to lift on site.
2 Construction scheme
The cabinet body adopts the "formal installation method", and is assembled in the order of first cabinet bottom and piston bottom, then wall plate (lower, middle and upper circles), and finally cabinet top. The cabinet bottom plate and piston bottom plate shall be laid and welded on site. In order to reduce the workload of field and high-altitude operations, the "cabinet wall panel" is divided into 54 pieces (7 pieces with "columns" on both sides, 27 pieces without "columns" on both sides, and the "columns" are H-shaped steel), which are prefabricated on the mould in the plant. After being transported to the site, the "cabinet wall panel" is assembled into a whole cabinet wall by pressing down, middle and upper three circles (18 pieces in each circle, 9 pieces in each circle are columns on both sides). T fence and T fence flocculent platform, piston fence and annular platform are also prefabricated in the workshop in sections, and hoisted and assembled on site. After the cabinet top and its accessories are assembled and welded on the cabinet bottom plate and piston bottom electrode, they are lifted to the top of the column as a whole.