Apparatus and method for reducing pressure pulsations within drilling mud being pumped downhole by a plurality of pumps to thereby improve quality of mud-pulse telemetry. The apparatus may include a position sensor disposed in association with each pump and operable to generate a position signal indicative of operational timing of a corresponding one of the pumps, a surface telemetry device fluidly connected with the drilling mud and operable to output a telemetry quality signal indicative of the quality of mud-pulse telemetry, and a controller communicatively connected with the pumps, the position sensors, and the surface telemetry device. The controller may be operable to receive the position signal and the telemetry quality signal, and cause the pumps to change relative operational timing of the pumps based on the position signal and the telemetry quality signal to improve the quality of mud-pulse telemetry.

A fluid flow system may comprise an input line connected to a drilling system, one or more fluid flow lines connected to the input line, and an output line connected to the one or more fluid flow lines. The system may further include one or more valves disposed in each of the one or more fluid flow lines and one or more pressure sensors disposed in each of the one or more fluid flow lines. A method for controlling a fluid flow system may comprise moving a drilling fluid from a borehole into an input line of the fluid flow system, directing the drilling fluid through the input line into a fluid flow line, measuring a first pressure at a first pressure sensor in the fluid flow line, and measuring a second pressure at a second pressure sensor in the fluid flow line.

A fluid flow system may comprise an input line connected to a drilling system, one or more fluid flow lines connected to the input line, and an output line connected to the one or more fluid flow lines. The system may further include one or more valves disposed in each of the one or more fluid flow lines and one or more pressure sensors disposed in each of the one or more fluid flow lines. A method for controlling a fluid flow system may comprise moving a drilling fluid from a borehole into an input line of the fluid flow system, directing the drilling fluid through the input line into a fluid flow line, measuring a first pressure at a first pressure sensor in the fluid flow line, and measuring a second pressure at a second pressure sensor in the fluid flow line.

A fluid pulse generator can include a fluid motor and a bypass flow path in fluid communication with an inlet and an outlet, and a flow control device configured to permit flow through the bypass flow path in response to a predetermined pressure differential applied across the flow control device. A method of generating fluid pulses can include flowing a fluid through a fluid pulse generator, thereby generating fluid pulses, and then applying a predetermined pressure differential from an inlet to an outlet of the fluid pulse generator, thereby permitting flow of the fluid through the fluid pulse generator without generating the fluid pulses. A fluid pulse generation system can include a fluid pulse generator with a fluid motor, a variable flow restrictor, and a bypass flow path. A predetermined pressure differential applied across the fluid motor permits the flow of the fluid through the bypass flow path.

A fluid pulse generator can include a fluid motor and a bypass flow path in fluid communication with an inlet and an outlet, and a flow control device configured to permit flow through the bypass flow path in response to a predetermined pressure differential applied across the flow control device. A method of generating fluid pulses can include flowing a fluid through a fluid pulse generator, thereby generating fluid pulses, and then applying a predetermined pressure differential from an inlet to an outlet of the fluid pulse generator, thereby permitting flow of the fluid through the fluid pulse generator without generating the fluid pulses. A fluid pulse generation system can include a fluid pulse generator with a fluid motor, a variable flow restrictor, and a bypass flow path. A predetermined pressure differential applied across the fluid motor permits the flow of the fluid through the bypass flow path.

The present invention relates to a riser system in the form of a pumped riser (1), i.e. a riser (1) having an outlet (6) from the riser (1) at a depth below the surface (S) of a body of water, where the outlet (6) is coupled to a return pump (7) to return fluid from the riser (1) to the surface (S), and various operational methods to facilitate greater versatility when performing hydrocarbon drilling related operations. The arrangement also comprises a sealing element (15, 16) to seal an annulus (5) of the riser (1), and a by-pass (17) around the sealing element (15, 16). Various methods makes it possible to switch between open mode and closed mode, and vice versa, monitoring leakage across the sealing element (15, 16), as well as performing other operations exploiting the advantages of the two different modes.

Methods determine a state of a well and comprise: receiving a set of well operations data comprising at least some measured well operations data; determining the occurrence of a well operations event based on the received data; evaluating one or more possible state transitions from a current well operations state to one or more possible new well operations states, the current state and the possible new states selected from a configurable plurality of well operations states, wherein evaluating the one or more possible state transitions is based on the current state, the determined event and the received data and wherein evaluating the one or more possible state transitions comprises determining a confidence level associated with each of the possible new states; and determining one of the possible new states to be a new predicted well operations state according to whichever possible new state has a highest confidence level.

Methods determine a state of a well and comprise: receiving a set of well operations data comprising at least some measured well operations data; determining the occurrence of a well operations event based on the received data; evaluating one or more possible state transitions from a current well operations state to one or more possible new well operations states, the current state and the possible new states selected from a configurable plurality of well operations states, wherein evaluating the one or more possible state transitions is based on the current state, the determined event and the received data and wherein evaluating the one or more possible state transitions comprises determining a confidence level associated with each of the possible new states; and determining one of the possible new states to be a new predicted well operations state according to whichever possible new state has a highest confidence level.

A full-metal anti-high temperature cycloid downhole motor comprises an outer tube, a stator, a rotor, a partition plate, a flow distribution disc, and a flow guide mechanism. The inside of the stator is provided with N grooves , the inner side walls of the N grooves form an annular inner contour surface; the rotor is formed with N−1 rotating heads provided along the axial direction of the outer tube, and each rotating head is provided with an embedding slot, one side of the embedding slot is provided with a notch, a rotor copper rod that can be in rolling engagement with the inner contour surface through the notch is provided in the embedding slot, and there is a changing gap between the outer wall of the rotor copper rod and the inner wall of the embedding slot.

A method for estimating the efficiency of hole cleaning of a well-bore during drilling operations includes (a) selecting at least one feature of the drilling operation for monitoring; (b) receiving, from a sensor, data regarding the at least one feature; (c) comparing the data to a predetermined condition for the at least one feature; (d) defining an event when the data meets the predetermined condition; (e) assigning a weight to the event based on a duration of the event; and (f) estimating an efficiency of the hole cleaning based on the event and the weight of the event. The at least one feature being selected from the list consisting of: hole angle, circulation, tight spot, static hole, and bit hydraulics.