A wellbore intervention tool conveyance system includes an upper pipe injector disposed in a pressure tight housing. The upper injector has a seal element engageable with a wellbore intervention tool and disposed below the injector. The upper housing has a coupling at a lower longitudinal end. A lower pipe injector is disposed in a pressure tight housing, the lower housing has well closure elements disposed above the lower pipe injector. The lower housing is configured to be coupled at a lower longitudinal end to a subsea wellhead. The lower housing is configured to be coupled at an upper longitudinal end to at least one of (i) a spacer spool disposed between the upper pipe injector housing and the lower pipe injector housing, and (ii) the lower longitudinal end of the upper pipe injector housing.

A method of estimating a state of a rotary steerable drilling system comprising applying a control input to a rotary steerable drilling system, sensing an actual output of the rotary steerable drilling system, inputting the control input into a mathematical model of the rotary steerable drilling system, receiving an estimated output of the rotary steerable drilling system from the mathematical model, generating an error compensation signal based on a difference between the actual output and the estimated output, and applying the error compensation signal to the mathematical model.

A downhole pump is used for a reciprocating pump system having a rod string disposed in a tubing string. A barrel of the pump is disposed, and a plunger of the pump coupled to the rod string is movably disposed in the barrel. The plunger has an external surface disposed at an annular gap relative to the barrel's internal surface. The external surface has circumferential grooves defined thereabout that hold wipers. An inner ring of the wipers composed of a swellable material is engaged in the one or more circumferential grooves, while an outer ring composed of a second material is disposed about the inner ring. The swellable material of the inner ring energizes the outer ring in slideable engagement with the internal surface of the barrel.

A downhole pump is used for a reciprocating pump system having a rod string disposed in a tubing string. A barrel of the pump is disposed, and a plunger of the pump coupled to the rod string is movably disposed in the barrel. The plunger has an external surface disposed at an annular gap relative to the barrel's internal surface. The external surface has circumferential grooves defined thereabout that hold wipers. An inner ring of the wipers composed of a swellable material is engaged in the one or more circumferential grooves, while an outer ring composed of a second material is disposed about the inner ring. The swellable material of the inner ring energizes the outer ring in slideable engagement with the internal surface of the barrel.

Disclosed is a device for solid-state fluidized mining of natural gas hydrates in a shallow seabed, including: a sea surface support system, a pipeline delivery system, and an undersea drilling system. The sea surface support system includes a hydrate drilling vessel floating on seawater. The pipeline delivery system includes a continuous double-layer oil pipe, a recyclable conduit installed in a sediment cover, an open-hole steering packer installed outside the recyclable conduit. The undersea drilling system includes a hydrate slurry separator, a single screw pump, a hydraulic motor, a jet head and a differential pressure sliding sleeve close to the hydrate drill bit. The present invention has the following beneficial effects. The device achieves a multi-directionally horizontal drilling and production in the hydrate reservoir with a single well head, improving the drilling efficiency and single well production.

Disclosed is a device for solid-state fluidized mining of natural gas hydrates in a shallow seabed, including: a sea surface support system, a pipeline delivery system, and an undersea drilling system. The sea surface support system includes a hydrate drilling vessel floating on seawater. The pipeline delivery system includes a continuous double-layer oil pipe, a recyclable conduit installed in a sediment cover, an open-hole steering packer installed outside the recyclable conduit. The undersea drilling system includes a hydrate slurry separator, a single screw pump, a hydraulic motor, a jet head and a differential pressure sliding sleeve close to the hydrate drill bit. The present invention has the following beneficial effects. The device achieves a multi-directionally horizontal drilling and production in the hydrate reservoir with a single well head, improving the drilling efficiency and single well production.

A downhole pump is used for a reciprocating pump system having a rod string disposed in a tubing string. A barrel of the pump is disposed, and a plunger of the pump coupled to the rod string is movably disposed in the barrel. The plunger has an external surface disposed at an annular gap relative to the barrel's internal surface. The external surface has circumferential grooves defined thereabout that hold wipers. An inner ring of the wipers composed of a swellable material is engaged in the one or more circumferential grooves, while an outer ring composed of a second material is disposed about the inner ring. The swellable material of the inner ring energizes the outer ring in slideable engagement with the internal surface of the barrel.

A downhole pump is used for a reciprocating pump system having a rod string disposed in a tubing string. A barrel of the pump is disposed, and a plunger of the pump coupled to the rod string is movably disposed in the barrel. The plunger has an external surface disposed at an annular gap relative to the barrel's internal surface. The external surface has circumferential grooves defined thereabout that hold wipers. An inner ring of the wipers composed of a swellable material is engaged in the one or more circumferential grooves, while an outer ring composed of a second material is disposed about the inner ring. The swellable material of the inner ring energizes the outer ring in slideable engagement with the internal surface of the barrel.

A system and method for magnetic survey uses an autonomous vehicle configured to traverse over the area in a grid pattern with a magnetometer coupled to the autonomous vehicle and configured to obtain magnetic measurements at a controlled rate, the magnetometer obtaining a uniform sampling of the magnetic measurements in each grid of the grid pattern; and a processor configured to obtain the magnetic survey based on the magnetic measurements.

System and methods for optimizing parameters for drilling operations are provided. A target value of a user-selected operating variable is estimated for each stage of a drilling operation to be performed along a planned well path, based on a first set of wellsite data. Values of one or more drilling parameters are determined for performing each stage of the operation, based on the estimated target value of the operating variable for that stage. The target value of the operating variable is updated based on a second set of wellsite data obtained during a current stage of the operation. The values of the drilling parameters are optimized for subsequent stages of the drilling operation based on the updated target value. The planned path of the well is adjusted for the subsequent stages, based on the optimized drilling parameter values. The subsequent stages are performed along the adjusted path of the well.