| 摘要 |
<p>A kind of thread connection structure for a steel tube is provided. Said structure includes a steel tube factory end (1), a steel tube scene end (2) and a connecting hoop (3). The ends of the steel tube factory end (1) and the steel tube scene end (2) both have a male thread, and the connecting hoop (3) has a female thread; then after two steel tubes are jointed by the connecting hoop (3), the small end face (5) with the male thread of one steel tube's steel tube factory end (1) mutually and tightly contacts with that of the other steel tube's steel tube scene end (2). The male threads of the steel tube factory end (1) and the steel tube scene end (2) are right-hand screw thread or left-hand screw thread simultaneously, the thread pitch of the male thread of the steel tube factory end (1) is smaller than that of the male thread of the steel tube scene end (2), and the thread pitch of the female thread of the connecting hoop (3) screwing with the male thread of the steel tube factory end (1) is smaller than that of the female thread of the connecting hoop (3) screwing with the male thread of the steel tube scene end (2); or the rotation directions of the male threads of the steel tube factory end (1) and the steel tube scene end (2) are reverse. Said tube can be an oil tube, a sleeve or a pipeline tube used in an oil field. Said structure improves the comprehensive properties such as connection sealing property and anti-galling property.</p> |
