The manufacturing route for tinplate products（生产马口铁产品路线）.pdf

Corus Packaging Plus The manufacturing route for tinplate products From hot strip to tinplate The basic raw material for the production of tinplate products is hot rolled steel strip. The production process reduces this to the required thickness by cold-rolling. This rolled strip is then coated with tin or chromium in an electrolytic process. For some applications polymer coatings are applied for additional protection of the metal. Hot rolled strip The tandem mill has several stands the strip is passed through an alkaline Hot rolled steel strip is the raw material equipped with a four high arrangement bath through which an electric current for the production of tinplate. Large of rolls. At the bottom and top of each is passed. coils of steel, measuring about 2 – 3mm stand are large back-up rolls with two in thickness and weighing up to smaller working rolls in the centre Next the strip is scrubbed, rinsed, 25 tonnes, are supplied to the plant. through which the strip passes. By dried and rewound into coils. passing the hot strip through these 1 Acid bath pickling rolls, the strip is reduced to less than 4 Continuous annealing Processing begins with the pickling 10% of its original thickness. The strip Cold rolling makes the strip hard and of the hot rolled strip in an acid bath and rolls require lubrication with an oil brittle and in this condition it is to remove the iron oxide layer formed and water mixture. unsuitable for use as a packaging during rolling. After the continuous material. The strip requires annealing pickling process, the strip is rinsed, Water also provides essential cooling to restore it