Process for producing a high-grade steel tube and high-grade steel tube
AssigneeSandvik Materials Technology Deutschland GmbH
InventorsJonas GUHRS, Christofer HEDVALL, Thomas FROBOSE, Udo RAUFFMANN
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Abstract
A process for producing a high-grade steel tube includes the steps of: providing a tubular blank of an austenitic high-grade steel, wherein the high-grade steel comprises in weight % no more than 0.02% carbon, no more than 1.0% manganese, no more than 0.03% phosphor, no more than 0.015% sulfur, no more than 0.8% silicon, no more than 17.5% t to 18.5% nickel, no more than 19.5% to 20.5% chromium, no more than 6.0% to 6.5% molybdenum, no more than 0.18% to 0.25% nitrogen, no more than 0.5% to 1.0% copper,and a remainder of iron and unavoidable impurities; and cold-forming the blank into a tube.
Claims19
A method for manufacturing a stainless steel tube comprising the steps of:
- providing a tubular hollow of an austenitic stainless steel, wherein the stainless steel comprises:
- carbon in an amount of not more than 0.02 wt.-%,
- manganese in an amount of not more than 1.0 wt.-%,
- phosphor in an amount of not more than 0.03 wt.-%,
- sulfur in an amount of not more than 0.015 wt.-%,
- silicon in an amount of not more than 0.8 wt.-%,
- nickel in an amount from 17.5 wt.-% to 18.5 wt.-%,
- chromium in an amount from 19.5 wt.-% to 20.5 wt.-%,
- molybdenum in an amount from 6.0 wt.-% to 6.5 wt.-%,
- nitrogen in an amount from 0.18 wt.-% to 0.25 wt.-%,
- copper in an amount from 0.5 wt.-% to 1.0 wt.-%, and
- a remainder of iron and unavoidable impurities;
- cold forming of the hollow into a tube;
- coiling the tube;
- and
- annealing the coiled tube after the cold forming at a temperature in a range from 1,100° C. to 1,200° C.
The method according to, wherein after the annealing step, the method further comprises the steps of:
- decoiling the tube;
- cold forming the tube;
- coiling the tube;
- and
- annealing the coiled tube again at a temperature in a range from 1,100° C. to 1,200° C.
A stainless steel tube comprising;
- carbon in an amount of not more than 0.02 wt.-%;
- manganese in an amount of not more than 1.0 wt.-%;
- phosphor in an amount of not more than 0.03 wt.-%;
- sulfur in an amount of not more than 0.015 wt.-%;
- silicon in an amount of not more than 0.8 wt.-%;
- nickel in an amount from 17.5 wt.-% to 18.5 wt.-%;
- chromium in an amount from 19.5 wt.-% to 20.5 wt.-%;
- molybdenum in an amount from 6.0 wt.-% to 6.5 wt.-%;
- nitrogen in an amount from 0.18 wt.-% to 0.25 wt.-%;
- copper in an amount from 0.5 wt.-% to 1.0 wt.-%;
- and
- a remainder of iron and unavoidable impurities, wherein the stainless steel tube is coiled and in the coiled state has a hardness of less than 90 HRB.
Dependencies are inferred from the claim text.