The present invention pertains to an improvement in buttress- threaded tubular connections. In particular, the connection is improved by controlling the tubular member thread pitch diameter tolerance to .+-. 0. 0015 inch, to provide a thread bearing contact pressure which is relatively constant over the entire length of the connection. In addition, the improved connection provides a reduction in hoop stress of about 20% over known buttress-threaded tubing connections.PPThe present invention typically includes the use of variable make-up in combination with the control of the tubular member thread pitch diameter tolerance.
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