Patent · US Expired

Process for improved manufacture of shells for tunnel tubes

US4454978A · kind A · utility

1Cited by
5References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 3, 1983
Grant dateJun 19, 1984
Priority date
Expiry dateMay 3, 2003

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE02D29/073
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

This invention relates to improved apparatus and process for manufacture of tunnel modules and tunnel sections used to build underwater tunnel tubes. A collapsible fixture is situated to roll up flat steel plate into a circular shell for the tunnel modules. A hydraulic cylinder is utilized to adjust the diameter of the fixture without collapsing it, in order to close any gaps between the ends of the plate when it is rolled into a shell.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.