A downhole drilling motor, system, and method for using same are disclosed. A downhole drilling motor can include a power section stator having a first end, a second end, an internal cavity passing therethrough. The downhole drilling motor can further include a rotor assembly positioned and fully encased in the internal cavity. The rotor assembly includes a power section rotor, a drivetrain operably coupled to the power section rotor and a bearing set. The power section rotor is positioned at the first end within the internal cavity of the power section stator. The power section rotor, the drivetrain, and the bearing set are fully encased in the internal cavity of the power section stator. Additional apparatuses, systems, and methods are disclosed.

A downhole drilling motor, system, and method for using same are disclosed. A downhole drilling motor can include a power section stator having a first end, a second end, an internal cavity passing therethrough. The downhole drilling motor can further include a rotor assembly positioned and fully encased in the internal cavity. The rotor assembly includes a power section rotor, a drivetrain operably coupled to the power section rotor and a bearing set. The power section rotor is positioned at the first end within the internal cavity of the power section stator. The power section rotor, the drivetrain, and the bearing set are fully encased in the internal cavity of the power section stator. Additional apparatuses, systems, and methods are disclosed.

A hydraulic tool includes a stator and a rotor rotatably disposed within the stator. At least one of at least an inner portion of the stator and at least an outer portion of the rotor includes an insert comprising a hard material. A method of forming a hydraulic tool includes attaching at least one insert comprising a hard material to a surface of a stator or a surface of a rotor. A downhole motor or pump includes a stator and a rotor. The stator includes at least one insert comprising a hard material disposed over at least a portion of an interior surface thereof and a matrix material at least partially surrounding the at least one insert. The rotor includes at least one insert disposed over at least a portion of an exterior surface thereof and a matrix material at least partially surrounding the at least one insert.

A mud motor, system, and method for using same are disclosed. A mud motor can include a continuously formed power section stator housing having a first end, a second end, and an internal cavity comprising a series of stator lobes and a housing portion passing. The stator lobes can extend from the first end of the power section stator housing until a first end of a transition portion. The transition portion can form a unitary combination with the stator lobes. The mud motor further includes a rotor assembly including a power section rotor having rotor lobes to be disposed completely within the internal cavity. Additional apparatuses, systems, and methods are disclosed.

A downhole drilling motor, system, and method for using same are disclosed. A downhole drilling motor can include a power section stator having a first end, a second end, an internal cavity passing therethrough. The downhole drilling motor can further include a rotor assembly positioned and fully encased in the internal cavity. The rotor assembly includes a power section rotor, a drivetrain operably coupled to the power section rotor and a bearing set. The power section rotor is positioned at the first end within the internal cavity of the power section stator. The power section rotor, the drivetrain, and the bearing set are fully encased in the internal cavity of the power section stator. Additional apparatuses, systems, and methods are disclosed.

A downhole drilling motor, system, and method for using same are disclosed. A downhole drilling motor can include a power section stator having a first end, a second end, an internal cavity passing therethrough. The downhole drilling motor can further include a rotor assembly positioned and fully encased in the internal cavity. The rotor assembly includes a power section rotor, a drivetrain operably coupled to the power section rotor and a bearing set. The power section rotor is positioned at the first end within the internal cavity of the power section stator. The power section rotor, the drivetrain, and the bearing set are fully encased in the internal cavity of the power section stator. Additional apparatuses, systems, and methods are disclosed.

A uniaxial eccentric screw pump includes: a stator 32 having a female threaded inner peripheral surface; a rotor 33 configured to be insertable into the stator 32, and formed of a male threaded shaft body; an exterior body 31 configured to be movable between a first position where the exterior body 31 is capable of compressing the stator 32 and a second position where the exterior body 31 at least alleviates a compression state of the stator 32; and guide members 55, 56 configured to restrict a movement of the exterior body 31 in a circumferential direction of the stator while allowing a movement of the exterior body 31 in a radial direction of the stator by guiding an end portion of the exterior body 31.

The subject matter of this specification can be embodied in, among other things, a seal assembly that includes a compressible seal slidably mounted on a central longitudinal shaft of a rotor assembly, the seal having a first lateral surface adapted for contacting a first end surface of a first stator and a first end surface of the second stator and a first end surface of a first longitudinal vane and a first end surface of a second longitudinal vane, a compression member slidably mounted on the shaft, and a locking piston slidably mounted on the shaft, the locking piston including an opening sized to receive the shaft, an end surface adapted to contact the compression member, a circumferential surface sized to be received in the bore of the housing, and a lateral surface adapted to receive actuation fluid.

The subject matter of this specification can be embodied in, among other things, a seal assembly that includes a compressible seal slidably mounted on a central longitudinal shaft of a rotor assembly, the seal having a first lateral surface adapted for contacting a first end surface of a first stator and a first end surface of the second stator and a first end surface of a first longitudinal vane and a first end surface of a second longitudinal vane, a compression member slidably mounted on the shaft, and a locking piston slidably mounted on the shaft, the locking piston including an opening sized to receive the shaft, an end surface adapted to contact the compression member, a circumferential surface sized to be received in the bore of the housing, and a lateral surface adapted to receive actuation fluid.

A rotary compressor (100A) includes a closed casing (1), a compression mechanism (48), a lower end-face plate (34), and a communication hole (50). An oil reservoir (12) is formed at the bottom of the closed casing (1). The lower end-face plate (34) divides the oil reservoir (12) into a plurality of sections (12a) and (12b) in the vertical direction. The plurality of sections of the oil reservoir (12) communicate with each other through the communication hole (50). The communication hole (50) is located on the same side as a discharge port (8b) of the compression mechanism (48) with respect to a reference plane (H1).