Jinan color steel tile for C-beam we are not unfamiliar with, said simply that looks like the shape of the English letter in the "C" of a cold-formed steel, but which is divided into cold-rolled and hot C-beam. These are also two ways of forming. In addition, the forming methods of C-beam can be divided into: galvanizing, hot galvanizing, drilling and so on. What are the differences and similarities between these molding methods?
Both hot rolling and cold rolling are the forming processes of section steel or steel plate, which have a great influence on the microstructure and properties of steel. The rolling of steel is mainly hot rolling, and cold rolling is only used to produce small section steel and thin plate.
Jinan color steel tile C-beam
Cold rolled C-beam refers to the cold-rolled strip processed by cold bending, cold drawing and a series of cold processing at room temperature. Although the steel formed in this way has not undergone hot plastic compression, there are still more or less residual stresses in its section, which will have a certain impact on the bending characteristics of C-beam. However, the hot-rolled C-beam is formed by hot rolling, and the internal delamination phenomenon will appear, which greatly weakens the tensile capacity. What's more serious is that the interlaminar tearing may occur, which is very dangerous. And hot rolled C-beam also has residual stress, but this is due to the residual stress caused by uneven cooling. Under the action of external force, deformation, stability and anti fatigue properties will appear problems. To some extent, these are more dangerous.
Hot rolling can destroy the casting structure of ingot, refine the grain of steel and eliminate the defects of microstructure, so that the microstructure of steel is dense and the mechanical properties are improved. This improvement is mainly reflected in the rolling direction, so that the steel is no longer isotropic to a certain extent, and the bubbles, cracks and porosity formed during pouring can also be welded under the action of high temperature and pressure. Cold rolling has the advantages of fast forming speed, high yield and no damage to the coating. It can be made into a variety of cross-section forms to meet the needs of service conditions. Cold rolling can cause great plastic deformation of steel and improve the yield point of steel.
The main differences are: 1. Local buckling of section is allowed for cold-rolled formed steel, which can make full use of the bearing capacity after buckling, while local buckling of section is not allowed for hot-rolled steel. 2. The reason of producing residual stress is different between hot rolled section and cold rolled section, so the distribution of residual stress on section is also different.
Domestic construction steel market prices continue to maintain a downward trend, but the overall market compared with the previous two weeks appeared more obvious changes. The price of construction steel continued to fall in most parts of the country, with a drop range of 20-70 yuan per ton, the same below, and a drop of 100 yuan in some areas. However, the price of rebar futures market rebounded sharply, which obviously curbed the downward trend of spot.
The domestic stock market and futures market rebounded sharply, the price decline of the spot market slowed down significantly, and the market confidence recovered. In this case, the possibility of the price continuing to decline significantly is decreasing. However, the price is also difficult to rise significantly when the demand is relatively weak, the unified bullish atmosphere is not formed, and the intermediate trading is difficult to be obviously active. It is expected that the domestic steel market price will rise significantly this week It mainly fluctuates in a small range.
Jinan color steel tile C-beam