| 摘要 |
<p>A snubbing rig comprises a device for feeding a pipe (32) into or out from an oil/gas well. The raising-lowering device includes an upper catcher means (22) having activatable-deactivatable catchers (34a, 34a') and a lower catcher means (26) having corresponding catchers (34b, 34b'). The catcher means (22, 26) are adapted alternately to grip firmly around the pipe (32) and to release the same, respectively, so that the pipe (32) at any time is retained by at least one catcher means (22 or 26; or 22 and 26), the upper catcher means (22) being displaceable vertically up and down by means of hydraulic piston cylinders (20a). In order to achieve a substantially continuous feeding of the pipe (32) in one or the other direction vertically, also the lower catcher means (26) has been assigned hydraulic piston cylinders (20b), so that the lower catcher means (26) can be brought to take its lower end position when the upper catcher means (22) takes the upper end position thereof, the lower catcher means (26) being displaced toward its upper end position while the upper catcher means (22) feeds the pipe (32) downwardly toward its lower end position, where the lower catcher means (26) takes over the pipe feeding downwardly.</p> |
