A stator element of a progressive cavity pump having a reinforcement tube having a longitudinal axis, an inner face (22), and an outer face, and an elastomer liner fixed to the inner face of the reinforcement tube, wherein a portion of the reinforcement tube has a substantially constant thickness (e) and in that said portion of the reinforcement tube is deformed such that it comprises at least a first relief pattern and a second relief pattern, the first relief pattern having the shape of a helical strip that is right-handed relative to the longitudinal axis, the second relief pattern having the shape of a helical strip that is left-handed relative to the longitudinal axis, the first and second relief patterns meeting in at least one section.

A sealing assembly for a progressive cavity pump and a progressive cavity pump assembly having a retaining sleeve, a ring, and an elastic diaphragm terminating in a first end of the diaphragm in a first opening, and in a second end of the diaphragm, opposite the first end, in a second opening larger than the first opening. The second opening is held in contact with the retaining sleeve by the ring, and the first opening is configured to grip a rotor of the progressive cavity pump, and the ring is configured to hold the second opening fixed with respect to a stator of the progressive cavity pump.

A stator for a downhole motor configured for use in a downhole environment. includes an inner tubular member formed from a first metallic material having an outer surface and a helically lobed inner surface, and an outer tubular member comprising a second metallic material that is different from the first metallic material. The inner tubular member is connected to the outer tubular member by compressive force passing from the outer tubular member through the inner tubular member to a rigid mandrel removably disposed within the inner tubular member. The inner tubular member and the outer tubular member form the stator of the downhole motor.

The invention relates to a bi-helical toothed wheel (1) with non-encapsulating profile for a hydraulic gear apparatus, of the type bound to a support shaft (5) to form a driving or driven wheel of the hydraulic apparatus and comprising a plurality of teeth (6) extended with variable helix angle with continuous function in the longitudinal direction, wherein the teeth profile keeps a shape continuity in each cross section thereof. More particularly, each tooth of the toothed wheel is longitudinally split in three zones: initial (A), central (B) and terminal (C) zones, and the central zone (B) has a variable helix angle, while the initial (A) and terminal (c) zones have a constant helix angle. The invention allows to manufacture contra-rotating rotors, having a non-encapsulating profile and a helix shape such as to suppress the angular point at the center of the rotors themselves and therefore all the problems related to their machining.

The invention relates to a bi-helical toothed wheel (1) with non-encapsulating profile for a hydraulic gear apparatus, of the type bound to a support shaft (5) to form a driving or driven wheel of the hydraulic apparatus and comprising a plurality of teeth (6) extended with variable helix angle with continuous function in the longitudinal direction, wherein the teeth profile keeps a shape continuity in each cross section thereof. More particularly, each tooth of the toothed wheel is longitudinally split in three zones: initial (A), central (B) and terminal (C) zones, and the central zone (B) has a variable helix angle, while the initial (A) and terminal (c) zones have a constant helix angle. The invention allows to manufacture contra-rotating rotors, having a non-encapsulating profile and a helix shape such as to suppress the angular point at the center of the rotors themselves and therefore all the problems related to their machining.

Cylindrical symmetric volumetric machine (1), which machine (1) includes two cooperating rotors (6a, 6b), namely an outer rotor (6a) which is rotatably mounted in the machine (1) and an inner rotor (6b) which is rotatably mounted in the outer rotor (6a), whereby the machine (1) is provided with an electric motor (15) with a motor rotor (16) and a motor stator (17) to drive the outer and inner rotor (6a, 6b), characterised in that the electric motor (15) is mounted around the outer rotor (6a), whereby the motor stator (17) is directly driving the outer rotor (6a), and whereby the electric motor (15) extends along only a part of the length (L) of the outer rotor (6a) and the inner rotor (6b), whereby the motor (15) is located at an end (9b) of the inner rotor (6b) with a smallest diameter (D).

Cylindrical symmetric volumetric machine (1), which machine (1) includes two cooperating rotors (6a, 6b), namely an outer rotor (6a) which is rotatably mounted in the machine (1) and an inner rotor (6b) which is rotatably mounted in the outer rotor (6a), whereby the machine (1) is provided with an electric motor (15) with a motor rotor (16) and a motor stator (17) to drive the outer and inner rotor (6a, 6b), characterised in that the electric motor (15) is mounted around the outer rotor (6a), whereby the motor stator (17) is directly driving the outer rotor (6a), and whereby the electric motor (15) extends along only a part of the length (L) of the outer rotor (6a) and the inner rotor (6b), whereby the motor (15) is located at an end (9b) of the inner rotor (6b) with a smallest diameter (D).

A progressive cavity pump includes at least one of a jacketed stator casing and a jacketed inlet body. The jacketed stator casing includes a stator heating chamber, a stator assembly, and a rotor rotatably disposed within the stator assembly. The stator heating chamber forms a first space around the stator assembly and receives heating fluid therein. The stator assembly includes a cylindrical wall and a stator segment that forms a helically-convoluted chamber within the cylindrical wall. The jacketed inlet body includes an inlet heating chamber and a working fluid chamber in fluid communication with the helically-convoluted chamber. The inlet heating chamber forms a second space around the working fluid chamber and receives heating fluid therein. The stator heating chamber and the inlet heating chamber are isolated from each other, the helically-convoluted chamber, and the working fluid chamber.

A progressive cavity pump includes a torque input disposed on a rotational axis, a resilient stator cylinder, a screw rotor situated within the resilient stator cylinder, and a universal joint. The universal joint rotationally couples the screw rotor to the torque input, and includes a swivel block, a linkage, a universal joint coupler, and a fastener. The swivel block has opposite laterally extending trunnions. The linkage extends parallel to the rotational axis, and laterally captures the laterally extending trunnions. The universal joint coupler is disposed around the swivel block and adjacent the linkage. The fastener connects the universal joint to the swivel block. The fastener and the laterally extending trunnions cooperate to transmit torque about the rotational axis through the linkage, while permitting lateral translation of the universal joint coupler in a plane orthogonal to the rotational axis.

The invention relates to fluid drive systems used in fluid wells and brake systems for permanent magnet wellhead direct drives. The braking controller connects or disconnects a brake resistor from a back EMF. A variable frequency drive (VFD) drives the motor and communicates with the control circuitry of the brake controller. The control circuitry monitors the brake resistor and depending on the rotational speed and direction of the motor and operating state of the VFD, disconnects or connects the brake resistor. If the direction of the motor is in reverse and above a threshold speed, it connects the brake resistor. If the direction of the motor is in reverse and below the threshold speed, the control circuitry dissipates stored back EMF through the brake controller. The amount of stored back EMF corresponds to the time to empty a pump.