Stainless steel composite plate

Stainless steel composite plate
Stainless steel composite plate is a composite steel plate made of a carbon steel base and a stainless steel cladding. Its main feature is that carbon steel and stainless steel form a strong metallurgical bond. It can be processed by hot pressing, cold bending, cutting, welding and other processes, and has good process performance.

The base material of the stainless steel composite plate can use various ordinary carbon steels and special steels such as Q235B, Q345R, 20R. The cladding material can use various grades of stainless steel such as 304, 316L, 1Cr13 and duplex stainless steel. The material and thickness can be freely combined to meet the needs of different users. Stainless steel composite plate not only has the corrosion resistance of stainless steel, but also has the good mechanical strength and processing performance of carbon steel. It is a new type of industrial product. Stainless steel composite plate has been widely used in petroleum, chemical, salt, water conservancy and electricity, and other industries. As a resource-saving product, stainless steel composite plate reduces the consumption of precious metals and greatly reduces the project cost. It achieves a perfect combination of low cost and high performance, and has good social benefits.

Production method
How is stainless steel composite plate produced? There are two main methods for industrial production of stainless steel composite plates, explosive composite and hot-rolled composite.
The production process of explosive composite plates is to overlap stainless steel plates on carbon steel substrates, and use pads to separate the stainless steel plates and carbon steel substrates at a certain distance. Explosives are laid flat on the stainless steel plates. The energy of the explosive explosion causes the stainless steel plates to hit the carbon steel substrate at high speed, generating high temperature and high pressure to achieve solid-phase welding at the interface of the two materials. Under ideal conditions, the shear strength of the interface can reach 400 MPa per square millimeter.
The hot-rolled composite plate process is to roll the carbon steel substrate and stainless steel plate in a physically pure state under high vacuum conditions. During the rolling process, the two metals diffuse to achieve complete metallurgical bonding. Of course, in order to improve the wetting effect of the composite interface and improve the bonding strength, a series of technical measures must be taken in the physical and chemical treatment of the interface. The above two composite plate manufacturing methods both implement the national standard GB/T8165-2008. This standard is not equivalent to the Japanese JISG3601-1990 standard, and the main technical indicators are the same or higher than the Japanese standard.
Process characteristics
Characteristics of explosive composite process
1. Since explosive composite is cold processing, it can produce many kinds of metal composite plates other than stainless steel composite plates, such as titanium, copper, aluminum, etc.
2. Explosive composite can produce stainless steel composite plates with a total thickness of several hundred millimeters, such as some large bases and tube plates. However, it is not suitable for the production of thinner composite steel plates with a total thickness of less than 10 mm.
3. Explosive composite uses the energy of explosives to produce, which will cause vibration, noise and smoke pollution to the environment. However, the equipment investment is small, and there are hundreds of domestic explosive production plants of various sizes. Due to the limitations of weather and other process conditions, the production efficiency of explosive composite is low.
Characteristics of hot rolling composite process
1. It is produced using large medium plate rolling mills and hot rolling mills, so the production efficiency is high and the delivery speed is fast. The product format is large and the thickness can be freely combined. Stainless steel coating thickness above 0.5mm can be produced. However, the investment is large, so there are fewer manufacturers.
2. Due to the limitation of the compression ratio of rolled steel, hot rolling production cannot produce composite steel plates with a thickness of more than 50 mm, nor is it convenient to produce various small batches, round and other special shapes of composite plates. Advantages of hot-rolled composite plates 6, 8, 10 mm thin composite plates. Under hot rolling conditions, composite coils can be produced to reduce production costs and meet more user needs.
3. Under current technical conditions, hot rolling technology cannot directly produce non-ferrous metal composite plates such as titanium, copper, and aluminum.
In summary, the two completely different production processes have their own characteristics, exist and develop at the same time, and meet the diverse needs of different users. The explosive rolling method is a combination of the above two processes, which will not be repeated.
Cold-rolled stainless steel composite plate
On the basis of hot-rolled stainless steel composite plates, after annealing, pickling, cold rolling, intermediate annealing, pickling (or bright annealing), straightening and finishing, stainless steel composite coils (plates) suitable for civil use have been produced. The surface of the plate reaches the surface quality of the same series of stainless steel, and the yield strength is better than the same grade of stainless steel. The thinnest is 0.6mm.
Stainless steel composite plate has the characteristics of various carbon steels and stainless steels. It is popular with users for its excellent performance-price ratio and has broad market prospects. But interestingly, since the 1950s, after more than half a century of ups and downs in the development process, there are still many people who don’t know it. More people have not used it. It should be said that the market for stainless steel composite plates has gradually entered a mature period, but there is still a lot of development work to be done. The exploration and efforts of scientific and technological workers to build a resource-saving society will never stop.
Market field
Today, coal coking, coal gasification, synthetic ammonia, and fertilizers have become the main coal chemical industry in my country, and have been continuously and rapidly developed. The contradiction between the growth of domestic oil consumption and the supply and demand of oil, and the introduction and development of coal chemical industry technologies such as methanol to olefins and coal to oil have accelerated the speed of industrial construction, and enterprises engaged in the production of coking products have also grown rapidly like mushrooms after rain. Such as Wuxi Gangze Metal Materials Co., Ltd. and so on.
For the coal coking industry, because pipelines and equipment are in high temperature and corrosive environments for a long time, the equipment is severely corroded, and the service life of the equipment will be greatly reduced. Therefore, improving the corrosion resistance of equipment, extending the service life of equipment, and reducing the production cost of enterprises are important means to improve the competitiveness of enterprises.
Stainless steel composite plate is a metal composite material with pure stainless steel as the outer layer and carbon steel as the inner layer. This metal composite material of pure stainless steel and carbon steel is stainless steel composite plate. The emergence of stainless steel composite plate provides material guarantee for the manufacture and upgrading of coking equipment.
1. Using stainless steel composite plate to replace the original pure stainless steel plate can reduce the cost of equipment, while the use of equipment is not affected. Stainless steel composite plate can be used for desulfurization tower, ammonia evaporation tower, debenzene tower, etc., with low cost and corrosion resistance; taking debenzene tower as an example, using stainless steel composite plate instead of pure stainless steel plate can reduce the cost by more than 30%.
2. Stainless steel composite plate retains the corrosion resistance, wear resistance, antimagnetic properties and beautiful appearance of pure stainless steel, and also has the good weldability, formability, stretchability and thermal conductivity of carbon steel. It can be widely used in coking equipment to improve the corrosion resistance of coking equipment and extend the service life of equipment.
3. Stainless steel composite plates have good thermal conductivity and anti-corrosion function, and can be widely used in coking equipment. For example, if they are used in ammonia evaporation towers, they can increase the service life of ammonia evaporation towers and reduce operating costs; on the other hand, due to their anti-corrosion properties, they can also be used in ammonia evaporation equipment.
In short, my country’s stainless steel composite plates have great potential in the manufacture, upgrading and transformation of coking equipment. They are the only choice to increase the service life of equipment, improve equipment production efficiency and reduce operating costs.