C21D 9/44
Heat treatment: for equipment for lining mine shafts
Official title: for equipment for lining mine shafts, e.g. segments, rings or props
C21D9/44 (Heat treatment: for equipment for lining mine shafts) appears on 6 US grants and 9 published applications in this corpus.
Search patents in C21D- Granted patents
- 6
- Published applications
- 9
- Assignees
- 12
- Inventors
- 42
- Latest grant
- 22 Jul 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 2002 | 0 | 1 |
| 2003 | 0 | 0 |
| 2004 | 1 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 1 |
| 2011 | 0 | 0 |
| 2012 | 1 | 0 |
| 2013 | 0 | 0 |
| 2014 | 0 | 1 |
| 2015 | 0 | 2 |
| 2016 | 1 | 0 |
| 2017 | 0 | 1 |
| 2018 | 0 | 1 |
| 2019 | 1 | 0 |
| 2020 | 0 | 0 |
| 2021 | 1 | 0 |
| 2022 | 0 | 1 |
| 2023 | 0 | 0 |
| 2024 | 0 | 0 |
| 2025 | 1 | 0 |
| 2026 | 0 | 1 |
By publication year. 2026 runs to 8 Oct.
Recent patents
- Drill string component with high corrosion resistance, and method for the production of same22 Jul 2025US 12,365,960 B2Schoeller-Bleckmann Oilfiend Technology GmbH
- Enhanced wear resistant steel and methods of making the same26 Oct 2021US 11,155,905 B2ExxonMobil Research and Engineering Company
- Precipitation hardened martensitic stainless steel and reciprocating pump manufactured therewith9 Jul 2019US 10,344,758 B2A. Finkl & Sons Co.
- Recrystallization, refinement, and strengthening mechanisms for production of advanced high strength metal alloys15 Mar 2016US 9,284,635 B2The NanoSteel Company, Inc.
- Fire resistant steel excellent in high temperature strength, toughness, and reheating embrittlement resistance and process for production of the same17 Jan 2012US 8,097,096 B2Nippon Steel Corporation
- Drill String Component With High Corrosion Resistance, And Method For The Production Of Same30 Apr 2026US 2026/0117335 A1Schoeller-Bleckmann Oilfield Technology GmbH
- Drill string component with high corrosion resistance, and method for the production of same3 Feb 2022US 2022/0033924 A1Schoeller-Bleckmann Oilfield Technology GmbH
- Enhanced wear resistant steel and methods of making the same13 Sep 2018US 2018/0258515 A1ExxonMobil Research and Engineering Company
- Precipitation Hardened Martensitic Stainless Steel and Reciprocating Pump Manufactured Therewith12 Oct 2017US 2017/0292515 A1A. Finkl & Sons Co.
- Recrystallization, Refinement, and Strengthening Mechanisms For Production Of Advanced High Strength Metal Alloys16 Apr 2015US 2015/0101714 A1The NanoSteel Company, Inc.
Most cited
By later US patents
- Fire resistant steel excellent in high temperature strength, toughness, and reheating embrittlement resistance and process for production of the same3US 8,097,096 B2Nippon Steel Corporation · 2012
- Precipitation hardened martensitic stainless steel and reciprocating pump manufactured therewith1US 10,344,758 B2A. Finkl & Sons Co. · 2019