Powder lubricant composition and method for manufacturing seamless steel pipe

Patent metadata

Field	Value
Publication number	US-10227540-B2
Application number	US-201314412783-A
Country	US
Kind code	B2
Filing date	Aug 13, 2013
Priority date	Aug 13, 2012
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

A powder lubricant composition according to the present invention includes 65 parts by mass to 95 parts by mass of sodium borate, and 5 parts by mass to 35 parts by mass of cryolite. A method for manufacturing a seamless steel pipe according to the present invention includes adhering the above-described powder lubricant composition to a pipe inner surface of a work piece which is piercing rolled to have a tubular shape, and elongation rolling on the work piece after the adhering of the powder lubricant composition.

First claim

The invention claimed is:

1. A method for manufacturing a seamless steel pipe, comprising:
adhering a powder lubricant composition to a pipe inner surface of a work piece which is piercing rolled to have a tubular shape; and
elongation rolling on the work piece after the adhering of the powder lubricant composition,
wherein the powder lubricant composition comprises:
sodium borate: 65 parts by mass to 95 parts by mass;
cryolite: 5 parts by mass to 35 parts by mass; and
at least one selected from the group consisting of a fatty acid sodium salt and a fatty acid calcium salt: 0 parts by mass to 25 parts by mass,
wherein a total of sodium borate and cryolite is 100 parts by mass,

and wherein a temperature of the work piece before initial rolling in the elongation rolling is 700° C. or higher and lower than 820° C.

2. The method for manufacturing a seamless steel pipe according to claim 1 , wherein
a total reduction in the elongation rolling is 50% to 80%.

3. The method for manufacturing a seamless steel pipe according to claim 2 , wherein
the elongation rolling is performed by a mandrel mill rolling.

4. The method for manufacturing a seamless steel pipe according to claim 1 , wherein
the elongation rolling is performed by a mandrel mill rolling.

5. The method for manufacturing a seamless steel pipe according to claim 1 , wherein a concentration of the sodium borate in the powder lubricant composition is 70 parts by mass to 95 parts by mass, and a concentration of the cryolite in the powder lubricant composition is 5 parts by mass to 30 parts by mass.

6. The method for manufacturing a seamless steel pipe according to claim 1 , wherein a concentration of the sodium borate in the powder lubricant composition is 70 parts by muss to 90 parts by mass, and a concentration of the cryolite in the powder lubricant composition is 10 parts by mass to 30 parts by mass.

7. The method for manufacturing a seamless steel pipe according to claim 1 , wherein a concentration of the sodium borate in the powder lubricant composition is 70 parts by mass to 80 parts by mass, and a concentration of the cryolite in the powder lubricant composition is 20 parts by mass to 30 parts by mass.

8. The method for manufacturing a seamless steel pipe according to claim 1 , wherein
the total of sodium borate and cryolite is 80 mass % to 100 mass % of the powder lubricant composition.

9. The method for manufacturing a seamless steel pipe according to claim 1 , wherein a concentration of the sodium borate in the powder lubricant composition is 65 parts by mass to 95 parts by mass, a concentration of the cryolite in the powder lubricant composition is 5 parts by mass to 35 parts by mass, and a concentration of the at least one selected from the group consisting of a fatty acid sodium salt and a fatty acid calcium salt is 5 parts by mass to 25 parts by mass.

10. The method for manufacturing a seamless steel pipe according to claim 1 , wherein
the elongation rolling starts when the work piece has a temperature of 700° C. or higher and lower than 820° C.

Assignees

• Nippon Steel & Sumitomo Metal Corp

Inventors

• Iida Sumio
• Imamura Masami
• Fukushima Takayuki

Classifications

• C10N2050/08

  Solids · CPC title

• C10N2040/241

  Manufacturing joint-less pipes · CPC title

• C10M2201/0873

  used as base material · CPC title

• C10M2201/081

  containing halogen · CPC title

• C10M169/04

  Mixtures of base-materials and additives · CPC title