Method for producing secondary mold elements
US6143235A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 3, 1998 |
| Grant date | Nov 7, 2000 |
| Priority date | — |
| Expiry date | Aug 3, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21C37/294
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method and a device for manufacturing secondary mold elements such as necks, protrusions, raised elongate flat locations and the like on elongate, circumferentially closed hollow shapes by means of internal-high-pressure shaping. The secondary mold element is shaped locally by widening of the hollow shape using a high-pressure fluid therein, and is supported under control during the shaping process by a counter plunger that expands outward with increasing shaping. In order to expand the method limits during the manufacture of a secondary mold element for an increase in its height in a safe and simple manner, the hollow section is upset inward by the counter plunger at the point where the secondary mold element is to be produced, whereupon the hollow shape material in the vicinity of the inward upsetting point is pressed circumferentially and endwise by the high-pressure fluid and the plunger. After the inward upsetting process, the hollow section is upset outward under internal high pressure by retracting the plunger that constantly abuts the hollow section, and the secondary mold element is formed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.