Plating solution for threaded connection for pipe or tube and producing method of threaded connection for pipe or tube
US10370770B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 15, 2015 |
| Grant date | Aug 6, 2019 |
| Priority date | — |
| Expiry date | May 15, 2035 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16L15/04
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Provided is a plating solution for a threaded connection used for forming a plating film excellent in galling resistance, crevice corrosion resistance, and exposure corrosion resistance. The plating solution contains no cyanide, but contains copper pyrophosphate, tin pyrophosphate, zinc pyrophosphate, pyrophosphate as a metal complexing agent, and a sulfur-containing compound of 40 g/L or less (excluding 0). The sulfur-containing compound includes: a mercapto compound and a sulfide compound defined by Chemical Formula (1); a dimer formed through a disulfide bond of the mercapto compounds; and one or more types of salts thereof: RS—(CHX1)m—(CHX2)n—CHX3X4 (1),
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.