Donald E Rasmussen

US Patent:

42708761, Jun 2, 1981

Filed:

Dec 27, 1979

Appl. No.:

6/107792

Inventors:

James D. Eklund - Mattawa WA
Joseph M. Halter - Richland WA
Donald E. Rasmussen - Spokane WA
Robert G. Sullivan - Richland WA
Robert B. Moffat - Federal Way WA

Assignee:

The United States of America as represented by the United States
Department of Energy - Washington DC

International Classification:

E21D 900

US Classification:

405133

Abstract:

The apparatus includes a cylindrical retainer form spaced inwardly of the wall of the shaft by the desired thickness of the liner to be poured and having overlapping edges which seal against concrete flow but permit the form to be contracted to a smaller circumference after the liner has hardened and is self-supporting. A curb ring extends downwardly and outwardly toward the shaft wall from the bottom of the retainer form to define the bottom surface of each poured liner section. An inflatable toroid forms a seal between the curb ring and the shaft wall. A form support gripper ring having gripper shoes laterally extendable under hydraulic power to engage the shaft wall supports the retainer form, curb ring and liner until the newly poured liner section becomes self-supporting. Adjusting hydraulic cylinders permit the curb ring and retainer form to be properly aligned relative to the form support gripper ring. After a liner section is self-supporting, an advancing system advances the retainer form, curb ring and form support gripper ring toward a shaft boring machine above which the liner is being formed.