A known method of production of steel bars or sheets for deep stretching to manufacture thin-wall cans provides for formation of up to 100 mm-thick slab from a liquid low-carbon steel in a continuos-casting installation, rolling of the slab in the austenitic zone and use of the heat released in casting, reduction of the slab to a blank intermediate thickness, cooling of the rolled slab down to the ferrite zone temperature, and consequent reduction of the slab from intermediate thickness (in the ferrite zone) to final thickness.

In the new technology, in the austenitic zone slab is rolled from initial thickness down to intermediate thickness (lower than 1.5 mm). General reduction from the intermediate thickness in the ferrite zone down to the final thickness is in the range of 75 to 90%.

The newly-developed method has several modifications. Chief peculiarities of the said modifications are as follows:

1. General reduction in the ferrite zone is below 87%.

2. Partially cold rolling starts in the ferrite zone, at least.

3. A slab, existed in the ferrite zone, consequently passes the first cold rolling line, a re-crystallization furnace and the second cold rolling line.

4. A slab, existed in the ferrite zone, is reduced in the first cold rolling line by a mill stand (one at least) with a reduction ratio of 30% per run.

5. A slab, formed from a liquid low-alloy steel, is reduced from its thickness in the ferrite zone to the targeted thickness of below 0.14 mm in the second cold rolling line.

6. A slab, formed from a liquid low-alloy steel, is rolled in the austenitic zone down to an intermediate thickness without cooling and remains in the said austenitic zone.

7. An up to 100 mm-thick slab is rolled in the austenitic zone to produce an intermediate slab. The temperature of the intermediate slab is leveled in one furnace at least. The intermediate slab is coiled in a coiling machine and after consequent re-coiling is rolled down to the intermediate thickness.

8. Unlike Pos.7, intermediate slab thickness is 5 to 25 mm (5 to 20 mm, preferably).

9. A slab is stayed in the austenitic zone in a non-oxidized gas atmosphere within a certain time.

10. Unlike Pos.7 and Pos.8, non-oxidized gas atmosphere is maintained in the said furnace or coiling machine at least when an intermediate slab exists over there.

PRONK Cornelis, etc.

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