Recent evolution of global tinplate and can lid technology

Recent evolution of global tinplate and can lid technology

Zhang Wencan

1. Chrome-plated iron and laminating iron
Tin is the main strategic resource, but developed countries do not have this mineral. So after World War II, the Bethlehem Steel Plant in the United States, with the cooperation of Heintz, built the first chrome-plated iron in 1953 (abbreviated as TFS or ECCS). production line. After that, the US Steel Corporation, Yangston Steel Plant, etc. also quickly followed up. So the United States is still one of the two countries that produce the most chrome-plated iron (with 15 production lines) and the other is Japan.
Japan later in the United States, in 1961, the first chrome-plated iron production line was established by Toyo Steel Co., Ltd. The product was named Hi-Top and mass-produced, and the quality was very good. At that time Fuji (the later Nippon Steel) company. It was also built in 1962, and after that, the chrome-plated iron production line, soon, Toyo Steel Pipe NKK, Hachiman, and Kawasaki all worked hard. When the output was the highest, eight production lines were used throughout Japan. After 1998, the output of Japanese chrome-plated iron TFS has remained above 600,000 tons, more than 50% of his total use. Especially in recent years, on the one hand, the price of tin has increased by 60-70% (from 50,000 yuan to 80,000 yuan / ton), on the other hand, the manufacture of chrome-plated iron is simpler than tin plating because it No need to reflow, just plating in chromic acid solution. In general, the normal TFS product has a corrosion resistance comparable to that of a tinplate of 2.8/2.8 g/?, while the adhesion to the inner and outer prints is much better than that of the tinplate. So before the 1990s, it was widely used in the United States and Japan. This can be covered from the cans of the United States (such as tomato sauce, asparagus, sweet corn, etc.), most of which can be confirmed by chrome-plated iron.
However, TFS has a great disadvantage, that is, both sides must be coated with a protective coating film, and the printing process will cause serious benzene pollution to the environment and humans. And some of the inevitable trace residues of many paints have been considered harmful to human health in the past 10 years.
Therefore, from Japan in the late 1980s, the laminating iron was successfully produced. In 1991, the laminating iron in Europe was also put into production. The film covered (bonded) by the laminating iron is a multi-layer polyester composite film (thickness of about 20-25 microns), which blocks the penetration of corrosive media. , far superior to the printed film, and close to "complete repression." Therefore, it can directly cover the multi-layer polyester composite film on the steel substrate without the tinplate which protects the tin layer. This completely abolished the food science cans (especially in other tanks) for more than a hundred years. In theory, only a steel substrate can be used. However, in practice, chrome-plated iron TFS is still used as a substrate in various countries.

Production of iron and steel in Asia and Europe in early 2005
Production plant output (tons) Total production (tons)

Nippon Steel Nagoya 170,000

490,000

Fukuyama 120,000

Toyo cans Simomatsu 200,000

Korea

TCC Toyo 55,000

105,000

Donbu Dongbu 50,000

Colas Corus Group

British Trostre 30,000

135,000

Belgium Duffel 40,000

Germany Rasselstain 50,000

Lorraine Sollac, France 15,000

As shown in the table, since the laminating iron eliminates the high pollution problem of printing and printing, and Japan has a small number of people, it has forced it to become a big country for production and all laminating iron (the total domestic consumption is about 1.2 million tons). 40%).
The laminating iron of Japan's major groups is highly complex due to the use of high-temperature lamination and rapid recrystallization techniques, etc., so the composite fastness is extremely high (as is the case in Western European countries). China's laminating technology has already started, but because of the low-temperature bonding, the adhesion fastness is not as good as that of Japan, and improvement is still needed.
Second, the progress of DRD stamping tanks and secondary cold rolled sheets
The skyrocketing tin resources and harsh environmental requirements have forced the rapid development of laminar iron in recent years. Also, due to various lamellar irons (including laminated aluminum), laminating iron (coated aluminum) which is not suitable for leaving is mostly. As a result, a wide variety of stamping tank DRDs (and cupping DI) are becoming more popular. The three-piece cans have been gradually reduced in developed countries due to the complicated production, and instead, the stamping cans DRD and the cupping DI are used. Their largest applications are in the field of food cans and beverage cans.
I have pointed out many times that in the developed countries, most of the empty cans with a volume of less than 1000 ml have been used as secondary empty-rolled sheets with a thickness of 0.16 mm or less. Here, if a three-piece can empty can, the conventional secondary cold-rolled sheet is of course no problem and can be competent. However, if used for DRD stamping food cans, the mechanical properties of the secondary cold rolled sheet must also greatly improve its ductility.
From the quality of secondary cold-rolled laminar iron, Corus Group cooperated with Crown cans to study the doubling of the two-piece cans for food. The problem of adaptability between secondary cold rolled sheets and existing equipment. The concrete result is: with the French Lorraine sheet plant as the representative, it produces the secondary cold-rolled laminating iron with excellent elongation. It is most suitable for two-piece stamping cans and easy-opening caps (required when manufacturing easy-opening rivets) The elongation of the sheet is excellent). They named this material "Malai board." Its performance is as follows:
Ordinary tinplate

It can be seen from the table that the elongation of the mane plate is 10% at the hardness of DR-8, and that of the ordinary plate is 3%. According to reliable information, Japan also has products similar to the Manet board. The key to making such a thin and good stretchable sheet is vacuum smelting during steel making, which greatly reduces the non-metallic content of the steel, including carbon and certain metals. (To dozens of PPM levels), there is such performance.
Third, easy to tear cover
In the past two or three years, ESE has become more popular in China, with an annual output of about 2 billion. Of course, the quantity and quality must be further improved.
However, in foreign countries, in recent years, it has gradually become popular as an Easy Peeled End. The cover is actually a secondary cold-rolled aluminum sheet or a secondary cold-rolled steel sheet with a thickness of 70-130 μm (0.07-0.13 mm), which is cleverly sealed on an empty can by mechanical and heating techniques. Due to the tearing of the use, certain types of EPE can withstand high temperature sterilization. Now, in the global empty cans appraisal organized by the International Can Making Association in recent years, the awards related to EPE easy to tear cover are listed below:

years

Type of prize

winner

Can lid name

1998

Cover award

Germany Lacroix Factory

EPE (gourmeT fileT) for meat cans

1999

Gold medal

Golden Ring Fruit Factory

EPE (made with Swiss equipment)

2002

Can gold medal

Colas Corus Group
Proflex plant

500ml beer can EPE
80-130μm secondary cold-rolled tinplate

2003

Silver medal

Crown Group

EPE (aluminum fish tank)

Can silver award

Crown Group

EPE (Pet Tin Can)

2004

Crown Group
Impression Group*

EPE
Fish tank EPE

2005

Can gold medal

Brazilian National Metallurgical Company

Aluminum easy to tear cover

Can Bronze Award

French Impression Group*

EPE (pet can)

Bronze medal

French Impression Group*

EPE (microwave food can)

It can be seen from the table that in 2005, there are 3 prizes in each of the four categories, including three-piece cans, three-piece cans, two-piece cans, and beverage cans. There are 12 prizes in total, and EPE accounts for 25% of the prizes. In addition, the world's largest The Easy Open Cover Manufacturing Group* is the US Sonoco Phoenix. It produces various types of EOE and EPE annually, with a total of 9 billion/year. The production plants are distributed as follows:

Production site

Production line volume

product type

Ohio, Canton

2 pieces

Iron easy to open cover (Fe EOE)

Kentucky, Henderson

1
1

Aluminum easy to open cover (Al EOE)
Aluminum easy to tear cover (Al EPE)

Tennessee, Memphis

1
2 pieces

Aluminum easy to tear cover (Al EPE)
Special cover, etc.

Wisconsin, Vaso

1

Aluminum easy to tear cover (Al EPE)

Brazil, Rayson

1

Iron easy to open cover (Fe EOE)**

Note**: Cover material is supplied by Brazilian National Metallurgical Company CSN (Companbia Siderurgica Nacional)
It can be seen from the table that although the aluminum easy-to-tear cover (AL EPE) iron easy-to-tear cover (Fe EPE) produced by it has no specific figures, it is estimated that the total amount will not be too small. The products of Soro? Phoenix are 80% sold to the United States and 20% to South America and Europe. Its EPE is of course also used to heat food. It is sold to: Boer Cans, Campbell Soups, Del Monte, Dole, Kraft Foods, Maxell Coffee, ConAgra's Sauces and Thai Pineapple Plants, etc. .
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Note*: The world's largest canning group, also one of the two largest tank makers in Europe, is Impress Holding. It has a plant with an annual output of 1.4 billion canned fish at Cuxhaven (80km northwest of Hamburg). It is 70% color-coated laminated aluminum cans. In its canning plant, there are 23 tank lines and 29 cover lines. The easy-opening cover (including EPE) has a total output of 7 billion/year, making it the second largest easy-opening plant in the world. Some of the products are EPE (square cover and 63-99 mm diameter dome). Its EPE production equipment was supplied by the Hans Rychiger plant in Switzerland in 1995. The annual sales of the Cuxhaven Fish Cannery is $7.2 billion. The Australian Packaging Containers Company (with six can making plants) also purchased Hans Rychiger's EPE equipment and technology in 1998.
Now Crown has four production plants in France and Italy, including Concorneau, which produces mainly canned meat (5 million cans per year) and uses Al EPE.
The canned fish factory of INESA Holding Company in Chile, South America, which has three plants in Chile and Argentina; one factory in Uruguay and Brazil, which has also adopted the EPE cover, which purchased the Alcan Rorschach AG plant in Switzerland. device of.
The Soudronic Group Company, in 2002, developed the "Universal Sealing Equipment", which can seal the EPE cover made of secondary cold-rolled sheet. The machine is 4 heads with 240 caps/min. The first of these machines is sold. middle East.
Therefore, from this point of view, easy to tear cover is a direction for future development. According to my judgment, it is still in the development stage. It has been reported that the cost of aluminum easy to tear cover is only 50% of the easy opening of aluminum. From the perspective of Europe and the United States, the technology of laminating aluminum is more mature than laminating iron. In addition, from the situation of building a laminating iron production plant in Australia in the past two years, they calculated that the laminating iron is cheaper than the aluminum sheet, which is contrary to the actual situation in China. The knowledge and mystery of it is worthy of our careful analysis and deduction.

In summary, in the past ten years, due to the harsh requirements of environmental protection and the growing shortage of resources, the global canning materials industry, canning industry and the cap manufacturing industry are undergoing revolutionary major changes. Secondary cold-rolled sheet, laminating iron, laminated aluminum, stamping cans, punching and pulling shaped cans and easy-to-tear covers are slowly becoming the mainstream of the can manufacturing industry in developed countries. The key (foundation) of these changes is the advancement of secondary cold-rolled iron (which is behind the advancement of steelmaking technology) and the development of laminating technology. This is very worthy of our attention and must be taken seriously. Otherwise, it will cause the whole industry to be passive and the loss is difficult to estimate.