Threaded joint for tube
US10295091B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 2014 |
| Grant date | May 21, 2019 |
| Priority date | — |
| Expiry date | Dec 14, 2035 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16L15/06
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A threaded joint is adapted for tubes where the stress or the strain concentration hardly occur at a threaded corner portion of box side even when the threaded joint receives repeated tensile-compressive forces or repeated bending forces. In a radial seal type threaded joint, tensile efficiency TE (%) defined by a ratio Sc/Sp between a cross-sectional area Sc, an area of Critical Cross Section (CCS) including a portion where a tensile stress and a strain become the highest in a tube circumferential cross section of a box and a cross-sectional area Sp of a tube body satisfies formula TE (%)≥2.25×t/ρ+99.9 having a ratio t/ρ between an internal thread height t of the box and a radius of curvature ρ of a corner portion of internally-threaded bottom load surface side.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.