Metal pipe and method for manufacturing metal pipe
US11945020B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 21, 2020 |
| Grant date | Apr 2, 2024 |
| Priority date | — |
| Expiry date | Jun 10, 2040 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21D26/043
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A metal pipe having an outer diameter of 150 mm to 3,000 mm and a wall thickness of 2 mm to 50 mm, and a method for manufacturing the same. The method includes a pipe-end-portion expansion step of expanding pipe end portions that are located at both ends of a mother pipe and an internal pressure application step that is performed after the pipe-end-portion expansion step and in which the mother pipe is expanded by applying an internal pressure, p, to the entire interior of the mother pipe until the internal pressure, p (MPa), that corresponds to changes in an axial compression amount s (mm), the axial compression amount, s, representing an amount of compression in a pipe axial direction against pipe extreme ends which are the both ends of the mother pipe, becomes a preset maximum internal pressure pmax (MPa), and p and s satisfy a specified formula.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.