Abstract: A rotating control device can include an annular seal, and a latch including a rotary cam and an engagement member which releasably secures the seal and/or a bearing relative to the housing, such that rotation of the cam relative to the housing displaces the member. A method of latching an annular seal relative to an outer housing of a rotating control device can include rotating a rotary cam, thereby linearly displacing an engagement member that releasably secures the seal relative to the housing while permitting rotation of the seal relative to the housing. Another rotating control device can include an outer housing, an annular seal, and a latch including a rotary cam and multiple separate engagement members disposed in the housing, and in which rotation of the cam relative to the housing displaces the members in the housing.

Abstract: A rotating control device can include an engagement member that secures relative to an outer housing an annular seal and/or a bearing, the member displacing in response to a pneumatic pressure differential. A method can include applying a pneumatic pressure differential, thereby displacing an engagement member that secures an annular seal relative to an outer housing, with rotation of the seal relative to the housing being permitted when the member is displaced to a position in which removal of the seal from the housing is prevented. A rotating control device can include a piston and an engagement member which secures an annular seal relative to an outer housing, the piston having piston areas exposable to a pneumatic pressure differential, and with increased pressure applied to another piston area of the piston displacing the piston to a position in which the member does not secure the seal relative to the housing.

Abstract: A rotating control device can include an annular seal, and a latch including a rotary cam and an engagement member which releasably secures the seal and/or a bearing relative to the housing, such that rotation of the cam relative to the housing displaces the member. A method of latching an annular seal relative to an outer housing of a rotating control device can include rotating a rotary cam, thereby linearly displacing an engagement member that releasably secures the seal relative to the housing while permitting rotation of the seal relative to the housing. Another rotating control device can include an outer housing, an annular seal, and a latch including a rotary cam and multiple separate engagement members disposed in the housing, and in which rotation of the cam relative to the housing displaces the members in the housing.

Abstract: Disclosed embodiments include a surge relief system for a bottom hole assembly (BHA) and drill bit on an offshore drill string. One embodiment includes flow passages and external ports arranged to manage flow of wellbore fluids during sudden movements of the BHA and drill bit caused by waves. A first relief valve in the first flow passage is disposed to activate at a predetermined pressure to allow flow therethrough. Additional flow passages and pressure relief valves may be sequentially positioned along the length of the BHA/drill bit system to further assist in a managed bleed of pressurized fluid through the surge relief system. The sequential pressure relief valves may have activation pressures that sequentially increase or decrease.