发明名称 |
Production method of seamless tube using round bar made of high Cr-high Ni alloy |
摘要 |
A continuously cast slab with a rectangular cross section, and made of high alloy containing Cr of 20 to 30 mass %, Ni of 30 to 50 mass %, and at least one of Mo and W as Mo+0.5W of 1.5 mass % or more is subjected to blooming and billet-making to yield a round bar having a diameter of 150 to 400 mm as a starting material of the seamless tube. The blooming and billet-making process is performed under a condition satisfying a relation of 1.3≦H/D≦1.8 where a short side length of the cross section of the cast slab is defined as H (mm), and the diameter of the round bar is defined as D (mm). The round bar is pierced-rolled to make a hollow blank; the hollow blank tube is elongation-rolled, and then diameter-adjusting-rolled to make the seamless tube, thereby preventing end cracking during piercing-rolling, and increasing yield. |
申请公布号 |
US9468959(B2) |
申请公布日期 |
2016.10.18 |
申请号 |
US201113996157 |
申请日期 |
2011.12.20 |
申请人 |
NIPPON STEEL & SUMITOMO METAL CORPORATION |
发明人 |
Hirase Naoya;Satou Takanori |
分类号 |
B21B1/04;B21B19/04;C21D9/00;C21D9/08;C22C30/00;C22C19/05;C22C38/00;C22C38/02;C22C38/04;C22C38/42;C22C38/44;C22C38/58;C22F1/10;B21B1/02;B21B3/02;B22D11/00;B21B23/00 |
主分类号 |
B21B1/04 |
代理机构 |
Clark & Brody |
代理人 |
Clark & Brody |
主权项 |
1. A production method of a seamless tube with a Mannesmann tube-making process comprising:
subjecting a continuously cast slab with a rectangular cross section, and made of high Cr-high Ni alloy containing Cr of 20 to 30 mass %, Ni of 30 to 50 mass %, and at least one of Mo and W as Mo+0.5W of 1.5 to 10 mass % to a blooming and billet-making process to yield a round bar having a diameter of 150 to 400 mm; subjecting the round bar to a piercing-rolling process through a piercing mill to yield a hollow blank; and subjecting the hollow blank to an elongation-rolling process through an elongation-rolling mill; followed by a diameter-adjusting-rolling process through a diameter-adjusting-rolling mill; wherein the blooming and billet-making process is carried out under a condition satisfying a relation of 1.3≦H/D≦1.8 where a short side length of the cross section of the cast slab is defined as H (mm), and the diameter of the round bar is defined as D (mm). |
地址 |
Tokyo JP |