Laser-welded steel pipe and method therefor
US6140601A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1999 |
| Grant date | Oct 31, 2000 |
| Priority date | — |
| Expiry date | Jun 28, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/909
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A laser welded steel pipe having a weld zone containing a steel pipe containing 0.01 to 0.2 weight % C, 1 weight % or less S, 0.05 to 2 weight % Mn and 6 weight % or less Mn. The weld zone has a melted and solidified metal structure containing carbon and oxygen which satisfy the following equations: EQU (carbon weight %)(oxygen weight %).ltoreq.0.006 for a steel pipe containing carbon in an amount of less than 0.2 weight %, and EQU (oxygen weight %).gtoreq.0.02. A method for manufacturing a laser-welded steel pipe including producing an open pipe made from a hot-rolled steel strip with opposing edge portions facing each other by employing a formal roll, preheating the two edge portions, pressing the two edge portions to butt against each other by using squeeze rolls and welding the butted edge portions by irradiation with a laser beam to heat and melt the two edge portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.