Cold rolling process for metal tubes
US7188501B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 2006 |
| Grant date | Mar 13, 2007 |
| Priority date | — |
| Expiry date | Jun 27, 2026 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21B38/04
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
In the cold rolling process by pilger rolling that holds a mandrel between each of paired roll-dies, by optimizing the side relief rate SR and the mandrel factors like the taper θ1 in the primary deformation zone of the mandrel and the taper θ2 in the final size reduction zone thereof, and the feed rate F of the workpiece material, and at the same time by properly adjusting the relationship between the side relief rate SR and the feed rate F, the dimension-related shape characteristics (near-perfect round shape) of the tube inside surface after the final finishing rolling process by pilger rolling can be ascertained to thereby ensure excellent surface property without requiring a new apparatus, and further without causing the decrease of the product yield and/or the increase of the manufacturing costs. Thus, this can be widely applied for producing steam generator tubes which exhibits high S/N ratio in the inner coil eddy current testing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.