Construction of the cast steel node common casting process
Publish Time: 2016-09-14 Origin: Site
Is widely used in modern construction, steel structure, such as gymnasium, factory building, exhibition hall, hotel buildings are more and more used in steel structure.Node is refers to the construction steel structure steel pipe in the intersection, its mechanical performance of the whole steel structure, engineering cost and ease of construction have important influence.Nodes of the casting process is also very important.
Cast steel node than welding has many advantages, contrast, use a wider range.Production is difficult, the cast-steel joints, choosing the reasonable casting process is very important.
Cast steel node common casting method is:
1, the sand mold casting
Mainly used sodium silicate sand casting process, it can get high quality casting quality, non-toxic harmless, more suitable for the large-scale steel production, the cast-steel joints.But the process generally use wooden modelling, along with the node shape diversification, wooden modelling, core making more difficult, and cast steel nodes are mostly single production, wood waste is serious;Node shape is complex, poorly designed prone to scrap pouring process parameters.
2, epc
The process does not require core, classification, steps, such as modulus is suitable for complex casting production.But C atoms in the shape of the combustion products to the casting surface, make the casting surface produces carbon or carbon defects such as inclusions, the cast steel nodes with weldability, the high demand for surface quality and chemical composition, the lost foam casting is not easy to meet this requirement;Moreover, the bubble shape in the process of modelling, such as tight, easy deformation;And disappearance mold casting of the strength of the sand mould is weak, when large casting sand mold casting due to gravity may be out of shape.
Therefore, pure epc and can't well meet the requirements of the production of cast steel node.
3, compound casting technology
Is the sand mold casting with epc, play to the advantages of two kinds of casting process and avoid their shortcomings, can be well adapted to the casting of the cast steel node.Specific principle is the original node thin-walled parts made of wooden sand core, outer contour shape node using foam instead of wood pattern to make;Solid foam in accordance with the sodium silicate sand molding, hardening after remove bubbles, then down into the wooden core can tanks on casting.
Composite casting process using the bubble shape both the advantages of low cost, high degrees of freedom of design, has kept the advantages of sand casting filling smoothly, the composition of cast steel node and size stability, to avoid the deformation and carbon defects such as inclusions.Composite casting process is production in recent years more popular a kind of casting process, the cast-steel joints.