Flowserve Corporation

Sean A Cain

Zachary Dennis

Andreas Dreiss

Howard G Thompson

Xiaonan Lu

Joseph Robert McManus

Ramakrishnan Rengasamy

Joseph Pitino

John M Knapp

Andrew J Brasher

Randal Perisho

Joseph Robert Mcmanus

John L Brown

An integral motor pump (IMP) or integral motor turbine (IMT) includes an axial field permanent magnet synchronous motor (PMSM) having a stator that is sealed by a disk-shaped non-conducting stator cover axially interposed between the stator and PMSM impeller, such that eddy currents are not generated in the stator cover by the rotating permanent magnets of the impeller. The stator cover can be annular, and can be fixed directly to the stator housing, or pressed against the stator housing by brackets. The seal can be formed by an adhesive, and/or by at least one gasket. Either the stator cover or the brackets can include flanges extending axially proximate the stator housing, and attached to the stator housing by any combination of an interference fit, an adhesive, set screws, or a protrusion extending into an indentation. In embodiments, the bracket flanges are welded to the stator housing.

Mechanism for reducing eddy current losses in sealless pumps and turbines having directly driven impellers

Systems and methods for preventing rotation of an ESP motor when the motor is not powered on, thereby preventing the motor from acting as a generator when fluid flowing through the pump section of the ESP applies a torque to the motor. In one embodiment, an ESP has a motor section, a pump section. The ESP may include a directional coupling that allows unidirectional rotation between the motor shaft and a pump shaft of the pump section, and a directional lock that allows unidirectional rotation between the motor shaft and a housing of the motor section. The directional coupling and directional lock allow the pump shaft to freewheel in the forward direction without causing the motor shaft to rotate, and prevent the pump shaft and motor from rotating in the reverse direction.

Systems and methods for prevention of rotation in permanent magnet motors

Axial bearing wear of a directly driven, axial, integral motor pump (IMP) or integral motor turbine (IMT) is monitored without use of sensors by estimating an axial rotor-stator gap according to a known dependence of the back EMF on the impeller rotation rate and the rotor-stator gap. The back EMF can be directly measured, for example between impulses of a variable frequency drive (VFD), or inferred from measurements of voltage applied to IMP stator coils and the resulting current. The rotation rate of an IMT impeller can be determined from a modulation frequency of the EMF. The rotation rate of an IMP impeller can be inferred due to its synchronicity with the applied, amplitude modulated power. A controller can record and report rotor-stator gap estimates over time, and can halt operation of the module if the estimated rotor-stator gap falls outside of a specified range.

Integral motor pump or turbine with sensorless monitoring of axial bearing wear

A system and method of pumping low-density liquids, such as liquid hydrogen (LH2), includes a plurality of integrated motor/pump modules (IMPs) interconnected in series, each having a single IMP impeller. A controller separately adjusts the speeds of the IMP impellers such that a specified head of the pumping system is achieved, while a critical NPSH_c of each IMP remains below its NPSH_A. The IMPs can be identical, and the controller can cause all of the impellers to rotate at the same speed, except for any that require a speed reduction to ensure that its NPSH_c remains below its NPSH_A. The IMPs can comprise induction coils or permanent magnets attached to the impellers that pass in proximate radial or axial alignment with stator coils. The IMPs can be controlled by variable frequency drives (VFDs). A cooling system can transfer heat from within the IMP to an external heat destination.

Efficient system for pumping low-density liquids

Growing community of inventors

Tulsa, OK, United States of America

Sean A Cain