Threaded joint for steel pipes
US7770935B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jan 11, 2006 |
| Grant date | Aug 10, 2010 |
| Priority date | — |
| Expiry date | Aug 16, 2027 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2050/08
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A threaded joint for steel pipes comprises a pin (1) and a box (2) each having a threaded portion (3a or 3b) and an unthreaded metal-to-metal contact portion (4a or 4b) as contact surfaces which contact each other when the joint is fastened. The contact surfaces (3a and 4a and/or 3b and 4b) of at least one of the pin (1) and the box (2) are coated with a lower layer of a solid lubricating coating containing a solid lubricating powder (e.g., molybdenum disulfide, tungsten disulfide, or graphite) and a binder (e.g., an epoxy or other organic resin) and an upper layer of a solid corrosion protective coating formed by an organic resin which does not contain solid particles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.