| 摘要 |
It is common practice to rotate casing in shallow holes (to approx. 1000m). This has been found to noticeably enhance the bond between the casing and cement and wellbore wall and cement and to decrease the chance of microchannelling along the annulus. The rotating casing assembly and method, as described herein, allows for rotation of the casing at any depth. Only the lower portion is rotated. This lower portion is generally that portion crossing the production zone. This method is extremely economical compared to other methods and requires no additional rig time or surface equipment. The casing is driven to rotate by the energy of the fluid being pumped through the casing and across vanes in the casing.
|
