Development of large drawing annealing equipment

In order to maintain this quenching solution, a large-scale annealing device has been developed. Several new products have been developed in different ways on the basic principles of metallurgy and the technical details of machinery and equipment.

(1) CAPL: Continuous quenching production line, R&D of Japanese state-owned steel enterprises:

(2) NKK-CAL: Japan National Seamless Steel Tube Continuous Annealing Line Zero Line, Japan National Steel Tube Company R&D;

(3) KM-CAL: Zero Line of Kawasaki Multifunctional Continuous Annealing Line, R&D of Kawasaki Steel Company of Japan:

(4) Howaq: boiling water heat treatment method, R&D of CRM in Denmark.

The difference of the processing methods first depends on the water cooling method at the beginning of annealing temperature. At this time, all the processing techniques follow the following understanding, that is, in order to obtain the desired physical properties of strip steel, the effective way is to first cool the strip with medium horizontal rate water, and then quickly cool the strip with water. In the CAPL method, the water is cooled first by the cyclone gushing water, and then by air and mist hydrate water. Some of the new CAPL generating units also carry out water cooling according to water cooling rollers or extremely reasonable steam gushing. In NKK-CAL method, the strip steel was first infiltrated into the water, resulting in a very large temperature drop. In this way, water-cooled heat dissipation rollers are also used to obtain a smaller water cooling rate. If strip steel penetrates into water and chills sharply, it must be reheated when aging treatment is carried out. KM-CAL method is characterized by water cooling consisting of steam gushing and water cooling rollers. According to the change of hydrogen moisture content in vapor atmosphere, water cooling rate can be harmed.

In Howaq method, strip steel is first cooled in boiling water at medium horizontal rate, and then the over-aging temperature can be obtained immediately after the change of waiting time in boiling water tank. If there is a need, reasonable mist water cooling can cool the strip steel deepening water to the indoor temperature. Since the world's first perfect cold-rolled plate column continuous annealing line zero line (CAPL) was put into industrial production in Junli Steelmaking Plant of Nippon Iron and Steel Company in 1972, the global steel industry has paid great attention to the continuous annealing process, and has rapidly developed and designed new technology and technology incorporating various commodity regulations. Surgical equipment. Since the 1970s, more than 60 cold-rolled steel sheets have been built and put into operation. There are more than ten countries in the world with continuous withdrawal. The cold-rolled steel sheets manufactured by Japan with continuous withdrawal process account for about 80% of the total output. The continuous annealing furnace can not only produce cold-rolled steel sheets with general stamping dies, but also cold-rolled steel sheets with deep stamping dies and super-excavation stamping dies for cars and hard primed steel sheets with spray paint. That is, tin-plated purple sheets with hard plastic can be produced, and soft-plastic tin-plated purple sheets can also be produced. It can produce cold-rolled steel sheets with normal compressive strength level, and cold-rolled steel sheets with high strength and ultra-wide compressive strength, such as fine-grained reinforced carbon steel and dual-phase steel.