| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide the screw joint for an oil well pipe excellent in an air tightness for restraining the occurrence of a goaling against the repeated tightening and loose back in the crude oil mining under such a high temperature environment as a deep oil well, high temperature oil well or vapour injection oil well. SOLUTION: A Cu plated layer 9 is formed on the nonthreaded metal contact part of at least either oneside of a pin 2 and box and a lubrication film 6 is further formed on the Cu plated layer 9, with an inorganic high polymeric compound whose skeleton is a resin or M (metal)-O dispersed and mixed molybdenum disulfied and/or graphite. Or the Cu plated layer 9 is formed on the nonthreaded metal contact part of either oneside of the pin 2 and box and the lubrication film of the inorganic high polymeric compound whose skeleton is the resin or M (metal)-O dispersed and mixed molybdenum disulfied and/or graphite is formed on the other nonthreaded metal contact part. The weight ratio (B/A) between the contact (A) of the inorganic high polymeric compound whose skeleton is the resin or M (metal)-O and the total content (B) of molybdenum disulfied and graphite is favorably 0.3∼0.9.</p> |
