Skin Herringbone Arrangement
Space triangle reticulated shell technology
The triangular reticulated shell structure of the top cover of the large-scale storage tank is divided into: KT type and joint square type grid, short-range line type grid, triangle type and sunflower type grid.
1. Various node forms of net shell:
The node forms of the spatial triangular mesh reticulated shell structure are divided into:
The end of the rod is made of a set of bolt holes and a plate node made of steel or aluminum plate, or a socket-type hub-shaped node triangle reticulated shell made by welding steel castings and rods. Its characteristics are as follows:
1. Three-way force transmission in space, with good stability, the structure itself has automatic forming and automatic rounding functions, which better control the installation quality and forming degree.
2. The parts are manufactured in a factory and standardized. The quality and machining accuracy of all parts are guaranteed by special templates and tooling molds, so the parts are of good quality and high precision.
3. The on-site construction is convenient, fast and efficient, basically no welding, which can save a lot of on-site construction period and basically realize the construction without moving fire, without any large lifting equipment.
two. The personality of steel mesh shell
The steel mesh shell is generally suitable for occasions where the storage medium has relatively slight corrosion of carbon steel. On the contrary, the steel mesh shell must be treated with anticorrosion. Domestic and foreign steel mesh shells are mainly used for the top cover of various storage tanks. It has the following characteristics:
1. The top cover of the storage tank is composed of a reticulated shell and a top plate. The reticulated shell is used as a force-bearing member of the top cover, and the top cover (skin) is only used as a sealing member. Therefore, a thinner plate can be used for the top cover, which greatly reduces the burden of the top Weight, the top cover is laid on the grid rods arranged in a triangle, and at the same time, a rod supporting point is added to the middle of each triangle rod, and the net shell is not welded. Therefore, the roof construction is convenient, and the appearance curve is smooth and beautiful.
2. The structure is light in weight, and the material saving rate of the reticulated shell top cover of the storage tank with a diameter of 30m or more is 20%-50% compared with the conventional plate rib structure. As the tank diameter is larger, the material is saved, which has obvious economic benefits.
3. The steel mesh shell is connected with the inverted channel steel on the wall of the storage tank, which increases the wind resistance of the top tank wall.
4. The oil tank attachment on the top cover of the steel mesh shell is arranged in the triangular grid of the mesh shell (if it collides with the rod of the mesh shell, it will be offset accordingly).
5. The steel reticulated shell structure can ensure that in the accident state, the top cover and the reticulated shell are not welded, and the top cover structure is not damaged. Only the damaged part of the top plate needs to be partially repaired, so the repair is convenient.
3. The personality of aluminum mesh shell:
The characteristics of the aluminum alloy material selected for the aluminum mesh shell are:
Light weight and corrosion resistance. Therefore, in addition to the wide application of aluminum alloy in building structures, European and American countries use aluminum alloy reticulated shells in large quantities for the top covers of storage tanks, wastewater treatment tanks and silos that have a strong corrosive environment for steel.
It has the following characteristics:
1. After the aluminum alloy reticulated shell and aluminum alloy top cover are adopted, the structural weight is greatly reduced, and the load-bearing capacity of the tank, pool and its foundation is correspondingly reduced. For example, the aluminum top cover with a diameter of 30-60m is 1/4~1/9 of the weight of the steel mesh shell top cover.
2. The aluminum alloy material has good corrosion resistance, so the aluminum reticulated shell top cover does not need to be anti-corrosive treatment on the top cover part, which saves anti-corrosion costs and indirect engineering costs. There is no need for maintenance during the entire service life, saving a lot of inspection and maintenance costs.
3. The radiant heat reflected by aluminum can reach 95%, so when the aluminum alloy reticulated shell top cover is used on the dome tank, the volatilization loss of volatile media can be reduced.
4. The strength of aluminum alloy material is higher at low temperature than at room temperature. It is an ideal material under low temperature conditions. Therefore, after the use of aluminum mesh shell and roof, the insulation material added to prevent the material from low temperature brittleness can be omitted during the entire service life. And costs.
5. After using aluminum alloy reticulated shell and top plate, the accessories set on the top of the oil tank, such as: platform, escalator, light hole, oil measuring hole, column passing device, etc., can also be changed to aluminum alloy material, and designed synchronously with the reticulated shell , Production.
6. The aluminum alloy top cover is connected to the inverted channel steel on the tank wall through the transition of the stainless steel support on the reticulated shell. The special sealing structure ensures the sealed connection of aluminum and steel, and also increases the stability of the tank wall.
7. When the aluminum mesh shell is used in construction, it can be designed and manufactured according to the technical parameters and requirements provided by the actual project.
8. The triangular aluminum reticulated shell has the common features of the above reticulated shells, but also has its safety:
1). High safety factor and reasonable structure. The above figure shows that in a triangular grid, the aluminum skin carried 15 people without any problems.
2). The aluminum cover of the reticulated shell can not only carry gravity, but also release the partial damage caused by the overpressure in the tank, effectively protecting the overall structure of the tank top reticulated shell and the oil storage tank from being affected.
3). The service life is long. The aluminum reticulated shells that have been built abroad for nearly 30 years are still in safe use. Our factory's diameter φ60 aluminum mesh shell has been in normal operation for many years.
Shanghai baoshan petroleum machinery factory
Add：No.268, Maojia Road, Baoshan District, Shanghai