Abstract: The present invention provides a method and apparatus for handling tubulars and drilling with tubulars such as casing into a formation. In one aspect of the invention, the apparatus comprises a circulating head and a cementing head operatively connectible to a gripping member. The circulating head is used to circulate drilling fluid while drilling with casing, and the cementing head is used to cement the casing string within the formation at a desired depth. The present invention also relates to methods and apparatus for isolating a tensile load from a drilling apparatus rotated by a top drive. In one aspect, the present invention provides a load isolator apparatus having an isolator body operatively connected to the top drive and a torque body at least partially disposed in the isolator body. In operation, the bearing assembly transfers the tensile load from the torque body to the isolator body.

Abstract: An apparatus for reducing pressure surges in a wellbore comprising a body having a bore therethrough, the bore providing a fluid path for wellbore fluid between a first and second end of the body, at least one fluid path permitting the wellbore fluid to pass between the bore and an annular area formed between an outer surface of the body and the walls of a wellbore therearound, and a number of closure mechanisms whereby the at least one fluid path is selectively closable to the flow of fluid.

Abstract: An apparatus for reducing pressure surges in a wellbore comprising a body having a bore therethrough, the bore providing a fluid path for wellbore fluid between a first and second end of the body, at least one fluid path permitting the wellbore fluid to pass between the bore and an annular area formed between an outer surface of the body and the walls of a wellbore therearound, and a number of closure mechanisms whereby the at least one fluid path is selectively closable to the flow of fluid.