Method and apparatus for performing cementing operations on top drive rigs

摘要

A remotely operated lifting top drive cement head is provided having a high tensile strength, as well as the ability to swivel or rotate about a central vertical axis. The cement head permits selective launching of darts, setting plugs, balls or other objects which can be held in place within the cement head without being damaged or washed away by slurry flow, but which can be beneficially launched into said slurry flow at desired point(s) during the cementing process. The internal components of the cement head can be easily accessed using interrupted thread connections that can be quickly and easy connected and disconnected in the field without requiring specialized equipment. The cement head can be rigged up and remotely operated without requiring the lifting of personnel off the rig floor to actuate the tool or observe tool status.

主权项

1. A cement head comprising:
a) a body member having an upper end defining at least one dog recess, a lower end and a bore extending from said upper end to said lower end, and a first box end threaded connector having interrupted threads at said upper end; b) a sub assembly having an upper end, a lower end, a bore extending from said upper end to said lower end, and a pin end threaded connector having interrupted threads disposed on said lower end, wherein said pin end connector is mated with said first box end threaded connector of said body member; c) a ring having a top, a bottom and at least one face dog, wherein said ring is slidably received on said sub assembly, and said at least one face dog is received within said at least one dog recess on said upper end of said body member; d) a locking assembly for selectively securing said ring against said body member; e) at least one droppable object disposed within said body member; f) a port extending through said body member; and g) a transparent window disposed over said port adapted to permit visual observation of said droppable object.