Abstract: A method of mitigating undesired pressure variations in a wellbore due to movement of a well tool string in a well can include selectively decreasing and increasing fluid communication between sections of a wellbore on opposite sides of at least one well tool in the well tool string, the fluid communication being increased in response to detecting a threshold movement of the well tool string relative to the wellbore. A well tool string can include a well tool connected in the well tool string, and having an enlarged outer dimension relative to adjacent sections of the well tool string, a flow passage extending between the well tool's opposite ends, a sensor, and at least one flow control device which selectively permits and prevents fluid communication between the opposite ends via the flow passage, in response to an output of the sensor indicative of movement of the well tool string.

Abstract: A method of mitigating undesired pressure variations in a wellbore due to movement of a well tool string in a well can include selectively decreasing and increasing fluid communication between sections of a wellbore on opposite sides of at least one well tool in the well tool string, the fluid communication being increased in response to detecting a threshold movement of the well tool string relative to the wellbore. A well tool string can include a well tool connected in the well tool string, and having an enlarged outer dimension relative to adjacent sections of the well tool string, a flow passage extending between the well tool's opposite ends, a sensor, and at least one flow control device which selectively permits and prevents fluid communication between the opposite ends via the flow passage, in response to an output of the sensor indicative of movement of the well tool string.

Abstract: Methods and assemblies that can be used to orient a second pipe with respect to a first pipe in a wellbore are disclosed. The first pipe may be a casing string that includes one or more recessed latch couplings, and the second pipe may be a tubing string that includes one more complementary radially extendable latch keys that may be received within the latch couplings. The tubing string may include one or more switches associated with the latch keys that are actuated when the latch keys are received within the latch couplings. The actuation of the switches is communicated to an operator at the surface via control lines within the tubing string.

Abstract: A method of mitigating undesired pressure variations can include flowing fluid between wellbore sections, thereby mitigating a pressure differential due to drill string movement, and the fluid flowing between the wellbore sections via a bypass passage extending through a drilling motor. A drill string can include a drilling motor, a bypass passage in the drilling motor, a sensor, and a flow control device configured to selectively increase and decrease fluid communication between opposite ends of the drilling motor via the bypass passage, in response to an output of the sensor indicative of drill string movement. A method of mitigating undesired pressure variations in a wellbore due to drill string movement can include selectively preventing and permitting fluid communication between wellbore sections on opposite sides of a drilling motor, the fluid communication being permitted in response to detecting a threshold drill string movement.

Abstract: Methods and assemblies that can be used to orient a second pipe with respect to a first pipe in a wellbore are disclosed. The first pipe may be a casing string that includes one or more recessed latch couplings, and the second pipe may be a tubing string that includes one more complementary radially extendable latch keys that may be received within the latch couplings. The tubing string may include one or more switches associated with the latch keys that are actuated when the latch keys are received within the latch couplings. The actuation of the switches is communicated to an operator at the surface via control lines within the tubing string.

Abstract: A method of mitigating undesired pressure variations in a wellbore due to movement of a well tool string in a well can include selectively decreasing and increasing fluid communication between sections of a wellbore on opposite sides of at least one well tool in the well tool string, the fluid communication being increased in response to detecting a threshold movement of the well tool string relative to the wellbore. A well tool string can include a well tool connected in the well tool string, and having an enlarged outer dimension relative to adjacent sections of the well tool string, a flow passage extending between the well tool's opposite ends, a sensor, and at least one flow control device which selectively permits and prevents fluid communication between the opposite ends via the flow passage, in response to an output of the sensor indicative of movement of the well tool string.

Abstract: A method of mitigating undesired pressure variations can include flowing fluid between wellbore sections, thereby mitigating a pressure differential due to drill string movement, and the fluid flowing between the wellbore sections via a bypass passage extending through a drilling motor. A drill string can include a drilling motor, a bypass passage in the drilling motor, a sensor, and a flow control device configured to selectively increase and decrease fluid communication between opposite ends of the drilling motor via the bypass passage, in response to an output of the sensor indicative of drill string movement. A method of mitigating undesired pressure variations in a wellbore due to drill string movement can include selectively preventing and permitting fluid communication between wellbore sections on opposite sides of a drilling motor, the fluid communication being permitted in response to detecting a threshold drill string movement.

Abstract: A method of providing substantially continuous circulation of fluid through a drill string and an annulus can include sealing off the annulus from atmosphere, regulating flow of the fluid from the annulus, thereby controlling pressure in the wellbore, and diverting flow of the fluid from a pump to an uppermost connector of the drill string and an inlet extending in a sidewall of the drill string, the regulating and the diverting being performed concurrently. A pressure and flow control system can include one or more flow control devices which divert flow from a pump to a valve which selectively permits and prevents communication between an uppermost connector of the drill string and a flow passage extending longitudinally through the drill string, and to a valve which selectively permits and prevents communication between the flow passage and an inlet extending in a sidewall of the drill string.