Metal, tinplate and the products derived from it.
Cold-rolled steel is a raw material used in the production of tinplate, galvanized steel, and polymer-coated steel. Due to the high strength of steel and the possibility of slitting and forging it with minimal tolerances, col-rolled steel found extensive use in mechanical engineering, shipbuilding and instrument making, as well as production of packaging.
Sheet steel covered with special anti-corrosive protective layer of tin is called tinplate. The application of a protective layer is performed by electrolysis. Sheet still without the protective layer of steel is called blackplate.
Originally, the tinplate production process was a secret (like the production of porcelain). For about 300 years the secret was only owed by Austria and Germany.
However, in 1665 the secret of making tinplate was stolen by the British, who gradually emerged as leaders in the field and overtaking the Germans not only by adopting their experience, but also creating proprietary production technologies.
In 1720, several tinplate plants were built in Wales that used hot-rolled metal sheets for as raw material, as well as improved etching and tinning processes, which enabled the British to seize the market and take the lead in manufacturing with the center in Wales.
In the first half of the 20th century, a system for the continuous rolling of steel strip was developed. In addition, in 1915 the first technologies for electrolytic tinning were developed. In 1930, electrolytic tinning of cold-rolled steel strip allowed to launch industrial production of tinplate in Germany. The Second World War served as a catalyst to the rapid spread of the electrolytic thinning method because of the interruptions in the supply of tin. In 1943, the United States also launched the production of tinplate by electrolytic tinning and in five years half of all the tinplate produced in the United States was produced by this method.
In the next thirty years, equipment for hot tinning of tinplate almost everywhere was replaced by electrolytic lines. In the years since, other technological developments such as continuous annealing, double rolling of cold-rolled steel tape and the use of differential coatings were introduced to manufacture of tinplate, which allowed to produce more than 13,000,000 tons of tinplate in 37 countries by 1980.
Rolled steel is classified based on the production method. The single-rolled sheet (SR) rolling and double (DR) types are distinguished, also by annealing type there is continuous annealing (CA) and annealing in bell-type furnaces (BA). By the method of applying a protective coating – electrolysis. The thickness of the tin can be from 0.10 to 0.4 mm, the form is usually sheet or rolls. The dimensions and weight of tin packs correspond to special technical standards; at the request of the customer tinplate can be cut or slit, according to the required specifications.