Keywords: Bar rolling
Description:
High-speed bar rolling technology is an advanced steel production technology. The bars produced have better mechanical properties and higher corrosion resistance, which not only improves the production efficiency and quality of the steel industry, but also has a broad market prospects.
High-speed bar rolling technology is an advanced steel production technology, which has many significant advantages compared with traditional bar rolling technology. These advantages include high efficiency, low cost, high quality, etc. High-speed bar rolling technology is suitable for rolling bars with a diameter of 5~50mm. It adopts rapid continuous rolling technology, and the produced bars have smooth surface, high dimensional accuracy, high yield, and extremely high production efficiency, greatly improving The production efficiency of steel mills. In addition, due to the more uniform size of the steel rolled by high-speed bar rolling, the produced bar has better mechanical properties and higher corrosion resistance, which is very suitable for use in the fields of automobiles, machinery, and electronics. Generally speaking, the application of high-speed bar rolling technology not only improves the production efficiency and quality of the steel industry, but also has a broad market prospect.
Full-short stress twist-free high-speed rolling
At present, advanced production lines in the world, such as the Italian ABSIWNA factory, use full-short stress line alternating vertical and non-twisted rolling.
Full hot charging direct rolling technology
Large quantities of materials and low energy consumption. Full hot charging direct rolling technology, represented by Japan’s NKK Takamori Plant, direct rolling of a large number of materials, and the way of supplementing heat at corners is an effective way to reduce costs and improve product competitiveness. Several factories in my country have also done this try. Currently, continuous casting hot charging and regenerative heating furnaces are widely used.
Controlled rolling and controlled cooling super steel technology
The use of low-cost materials to produce high-strength (400Mpa) threaded steel bars is a “973” scientific research project in my country. Trials have been carried out in Huaiyang, Nangang, Sanming and other bar factories, and some achievements have been made. It is predicted that products will enter the market soon. The new projects launched in 2002 basically considered the possibility of producing super steel.
Multi-line segmentation technology
The domestic two-wire slitting technology has been widely used, and the three-wire slitting technology has been successfully applied in several rolling mills and achieved expected benefits. The four-line split was only introduced by Guangzhou Iron and Steel from Baden, and it is still unstable at present. With the deepening of material research, the proportion of high-strength steel in the market will increase, and it has become an inevitable trend to replace the original medium and large specifications with small-sized products. It is very necessary to master and apply the multi-line cutting technology proficiently for the rolling bar production line.
Application of roll delivery technology
Foreign rolling mills, especially bar-wire composite production lines, produce Ф8~16mm rebar, and deliver them in coils, which greatly facilitates the different requirements of customers, especially for highways, airports, and large bridges. In recent years, some equipment manufacturing companies have specially designed and manufactured coilers for rod and wire production lines. Like the Italian POMINI company, the maximum specification can curl rods above Ф25. In addition to being directly used by households, most of these products are further processed and sent directly to the construction site.
Deep processing of thread steel
The foreign construction market has basically realized mechanization, and due to problems such as labor costs, more and more customers order deep-processed rebar products from processing and distribution centers instead of directly ordering from steel mills. In this way, customers can request the rebar processing line to deliver rebar products every day according to their own construction progress.
Application of cemented carbide roll ring in continuous rolling bar production line
Due to the requirements of producing small-scale products and reducing manufacturing costs, many production plants have begun to use cemented carbide roll rings. At present, the combined roller ring of SAAK in Germany is the most widely used. Five domestic companies have also begun to produce and put into use this kind of roller ring. From the perspective of its use effect, there is not much difference with foreign imports, but the processing is very difficult.
Automatic Counting Technology
The latest automatic counting uses an optical camera with a CCD (charge-coupled device, a semiconductor device that can convert optical images into digital signals) processing system, which can accurately read the number of strands per bundle, but cannot automatically divide bundles online To solve the problem of automatic counting, work can also be done on billet optimization and multi-scale optimization. The rack counting action before cold shearing can keep the number of steel in each batch consistent, and can also ensure that the number of steel in each bundle is strictly consistent.
What are the main equipment in the modern bar production line, and what are their main functions?
The modern bar production line mainly includes the following equipment: heating furnace, rolling mill, shearing machine, cooling bed, cold shearing, bundling machine, etc.
Heating furnace: It is used for preheating, heating and heating up the billet in the furnace, so that the billet has a certain plasticity to meet the rolling requirements of the rolling mill.
Rolling mill: the mill rolled piece undergoes plastic deformation between the rotating rolls, and the steel with the required cross-sectional shape and size is rolled out
No. 1 shear and No. 2 shear: used to cut the head and tail of the rolled piece or break it in an accident state.
No. 3 shear: Mainly perform double-length shearing and optimized shearing on the finished steel in a hot state.
Cooling bed: cooling and straightening all the rolled pieces to ensure the flatness of the finished rolled pieces.
Cold shearing: cut to length, which is convenient for processing and transportation down to the process.
Bundling machine: equipment for bundling the finished steel products after shearing according to requirements.
What is endless rolling?
Endless rolling and in the rolling process, the head and tail of the front and rear steel billets are welded together to achieve continuous billet supply and continuous rolling. In a roll changing cycle, the rolling method can extend the length of the rolled piece infinitely.
What is Endless Welded Rolling Technology?
The so-called endless welding rolling is the specific name of endless rolling. It uses the fixed-length steel billet in the traditional rolling production (the length is determined according to the specification and type of the heating furnace), and before entering the rough rolling, the head and tail of the two front and rear billets are welded together by the billet welding machine (at this time, the head of the billet has entered the roughing mill), and remove the weld bump, and enter the roughing mill as a billet, so as to realize endless rolling.
What are the advantages of headless soldering?
Endless welding rolling has the characteristics of increasing output, increasing yield and mill operating rate, reducing costs, facilitating production management, and strong adaptability.
(1) Increase production. The billet interval time is omitted, the effective production time is increased, and the output is improved: scrap products usually appear at the head of the bar, thus greatly reducing the scrap rate and the time consumed for generating scrap products: eliminating the loss of billet cutting head and tail cutting.
(2) The yield rate and rolling mill operation rate have been improved.
1) In the endless welding and rolling, one production shift can cut the head of the first billet and cut the tail of the last billet;
2) There is no need to optimize the length of the bar on the cooling bed for shearing operations. The shearing machine only cuts double lengths and does not generate short lengths;
