Threaded joint for steel pipes
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Dec 9, 2003
Grant Date -
Aug 28, 2003
app pub date -
Feb 11, 2003
filing date -
Apr 11, 2001
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
This invention relates to a threaded joint for steel pipes which comprises a pin and a box each having a contact surface including a threaded portion and an unthreaded metal contact portion and which guarantees galling resistance and gas tightness in a stable manner without application of a compound grease. A solid lubricating coating comprising a lubricating powder (e.g., molybdenum disulfide) and an organic or inorganic binder is formed on the contact surface of at least one of the pin and the box. The proportion of area of a cross section along the thickness of the solid lubricating coating which is occupied by secondary particles of the lubricating powder having an equivalent circular diameter of 15-60 .mu.m is from 5-90%. Alternatively, the solid lubricating coating comprises, in addition to the lubricating powder, a fibrous filler (e.g., inorganic whiskers) in such an amount that the mass ratio of the fibrous filler to the binder is 0.01-0.5. As a result, galling resistance is improved, particularly at high temperatures.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Advertisement
Advertisement
Advertisement
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully