Bell-and-spigot concrete pipe joint with plastic liner ring
US4084828A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 26, 1976 |
| Grant date | Apr 18, 1978 |
| Priority date | — |
| Expiry date | Jul 26, 1996 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16L21/035
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A thin-walled joint face liner ring providing a smooth and continuous face is applied to the bell or to both the bell and the spigot of concrete pipe. The outer end of the ring is formed as a reversely curved flange so that its edge enters and is buried in the concrete. Its inner end extends part way outward along the shoulder of the pipe and thence axially so that its edge also enters and is buried in the concrete. Each ring is applied by placing it on the usual joint face-forming portions of the pipe mold, casting the concrete against the ring and about its edges, and subsequently curing the concrete in place against the ring or rings. When used on the spigot face, it can be made to form the usual gasket groove at such end, and thereby permit use of a more simple mold structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.