B28B 21/02
Methods or machines specially adapted for the production of tubular articles: by
Official title: by casting into moulds
B28B21/02 (Methods or machines specially adapted for the production of tubular articles: by) appears on 126 US grants and 71 published applications in this corpus.
Search patents in B28B- Granted patents
- 126
- Published applications
- 71
- Assignees
- 83
- Inventors
- 217
- Latest grant
- 3 Feb 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 7 | 0 |
| 1977 | 5 | 0 |
| 1978 | 6 | 0 |
| 1979 | 0 | 0 |
| 1980 | 2 | 0 |
| 1981 | 4 | 0 |
| 1982 | 6 | 0 |
| 1983 | 4 | 0 |
| 1984 | 1 | 0 |
| 1985 | 1 | 0 |
| 1986 | 3 | 0 |
| 1987 | 6 | 0 |
| 1988 | 2 | 0 |
| 1989 | 1 | 0 |
| 1990 | 2 | 0 |
| 1991 | 5 | 0 |
| 1992 | 4 | 0 |
| 1993 | 3 | 0 |
| 1994 | 3 | 0 |
| 1995 | 3 | 0 |
| 1996 | 1 | 0 |
| 1997 | 2 | 0 |
| 1998 | 3 | 0 |
| 1999 | 3 | 0 |
| 2000 | 2 | 0 |
| 2001 | 1 | 0 |
| 2002 | 3 | 1 |
| 2003 | 0 | 5 |
| 2004 | 1 | 4 |
| 2005 | 2 | 5 |
| 2006 | 3 | 2 |
| 2007 | 0 | 2 |
| 2008 | 0 | 0 |
| 2009 | 0 | 2 |
| 2010 | 1 | 4 |
| 2011 | 1 | 6 |
| 2012 | 3 | 4 |
| 2013 | 3 | 2 |
| 2014 | 2 | 4 |
| 2015 | 1 | 2 |
| 2016 | 5 | 2 |
| 2017 | 3 | 1 |
| 2018 | 0 | 6 |
| 2019 | 4 | 4 |
| 2020 | 3 | 1 |
| 2021 | 1 | 4 |
| 2022 | 2 | 0 |
| 2023 | 2 | 3 |
| 2024 | 2 | 2 |
| 2025 | 3 | 2 |
| 2026 | 1 | 3 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Precast column and method of manufacturing the same3 Feb 2026US 12,540,473 B2Ruentex Engineering & Construction Co., Ltd.
- Adjustable magnetic support stand for pallet14 Oct 2025US 12,441,025 B2Hawkeyepedershaab Concrete Technologies, Inc.
- Lightweight aggregate-based non-steam-cured high-performance pipe culvert and preparation method thereof9 Sep 2025US 12,410,099 B1Kunming Shunhong New Materials Co., Ltd
- Pipe forming apparatus4 Feb 2025US 12,214,559 B2Nexgen Pipes Pte. Ltd.
- System and method for producing concrete products by a casting method13 Aug 2024US 12,059,820 B2
- Adjustable Magnetic Support Stand for Pallet16 Jul 2026US 2026/0200131 A1Hawkeyepedershaab Concrete Technologies, Inc.
- Core wall-thinning design method for prestressed high-performance concrete cylinder pipe22 Jan 2026US 2026/0022072 A1Zhengzhou University
- Adjustable Magnetic Support Stand for Pallet8 Jan 2026US 2026/0008203 A1Hawkeyepedershaab Concrete Technologies, Inc.
- Adjustable Magnetic Support Stand for Pallet24 Jul 2025US 2025/0236048 A1Hawkeyepedershaab Concrete Technologies, Inc.
- Method for manufacturing ceramic material, ceramic material and use of ceramic material3 Jul 2025US 2025/0214900 A1Petroleo Brasileiro S.A. - Petrobras
Most cited
By later US patents
- Process for slip casting textured tubular structures50US 6,335,065 B12002
- Self aligning concrete pipe with configured joint21US 4,565,381 A1986
- Concrete pipe making machine18US 4,708,621 AHawkeye Concrete Products Co. · 1987
- Acid resistant concrete articles, especially sulfur concrete pipes, and a method of manufacturing said articles18US 4,981,740 AKkkk A/S · 1991
- Machine and method for making concrete product17US 4,340,553 AHydrotile Machinery Company · 1982