B28B 21/74
Producing pipe bends, sockets, sleeves
Official title: Producing pipe bends, sockets, sleeves; Moulds therefor (combined with extrusion presses B28B21/54)
B28B21/74 (Producing pipe bends, sockets, sleeves) appears on 7 US grants and 0 published applications in this corpus.
Search patents in B28B- Granted patents
- 7
- Published applications
- 0
- Assignees
- 6
- Inventors
- 10
- Latest grant
- 22 Jan 2002
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 1 | 0 |
| 1978 | 3 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 1 | 0 |
| 1987 | 0 | 0 |
| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 1 | 0 |
By publication year. Applications have been published since 2001.
Recent patents
- Method and apparatus for producing molded tubular objects from polymer concrete22 Jan 2002US 6,340,442 B1
- Pipeline jointing16 Feb 1988US 4,725,165 AS.E.L. Services Limited
- Mold for producing concrete pipe30 Sep 1986US 4,614,324 ANippon Pressed Concrete Co., Ltd.
- Refractory pipe fittings and production thereof25 Jul 1978US 4,102,972 A
- Method of casting beveled pipe18 Jul 1978US 4,101,622 AAmeron, Inc.
No published applications in this class yet.
Most cited
By later US patents
- Mold for producing concrete pipe10US 4,614,324 ANippon Pressed Concrete Co., Ltd. · 1986
- Pipeline jointing9US 4,725,165 AS.E.L. Services Limited · 1988
- Bell-and-spigot concrete pipe joint with plastic liner ring8US 4,084,828 AConstruction Products Corporation · 1978
- System for finishing pipes5US 4,024,006 AU.S. Concrete Pipe Co. · 1977
- Method of casting beveled pipe2US 4,101,622 AAmeron, Inc. · 1978