Abstract: A method is disclosed for determining operability of a motor operated valve combination including a valve having a valve stem, a valve disc, a valve seat, and a motor operator having a motor drive interconnecting the motor to the valve stem for movement of the valve disc toward and into engagement with the valve seat to close the valve and a control switch for deactivating the motor. The method comprises the steps of sensing the real motor power of the motor as a function of time during valve closing with zero differential pressure applied to the valve at a first time. From the sensed information, the rate of motor power build-up is determined after the onset of valve wedging during valve closing at the first time. The real motor power of the motor is again sensed as a function of time during valve closing with zero differential pressure applied to the valve at a second time which is subsequent to the first time.

Abstract: An operating turbine monitor is described incorporating one or more acoustic sensors positioned next to a blade row of a rotor, an analog digital converter, a tachometer sensor at the rotor shaft, a memory, a synchronous averaging circuit, a subtractor circuit, and a comparator. The invention overcomes the problem of monitoring an operating turbine of order-related turbine blade vibration and for non order-related turbine blade vibration as well as for other turbine conditions.

Abstract: A system to determine the position of an electrically conductive element movably positioned in a housing, like a metal disc in a check valve, with greater accuracy and resolution than single magnet systems includes first and second A.C. electromagnets positioned in close proximity to the element on opposing sides of the housing. The magnets are excited with A.C. currents to generate magnetic fields which penetrate the housing and the element. The magnetic fields are sensed by a magnetic field sensor. A control portion of the system includes a microprocessor configured to allow an operator to adjustably select and set a common frequency, individual amplitudes and a phase difference between the two currents supplied to the two magnets so that the currents might be adjusted to cause the magnets to generate magnetic fields at least partially and preferably essentially cancelling one another at the sensor.

Abstract: A system to determine the position of an electrically conductive element movably positioned in a housing, like a metal disc in a check valve, includes an A.C. electromagnet positioned in close proximity to the valve casing and the disc. The magnet is excited with an A.C. voltage to generate a magnetic field which penetrates the casing and the disc. The magnetic field is detected by a sensor. A.C. current and voltage signals from the electromagnet and a magnetic field signal from the sensor are presented to a processor portion of the system. The processor portion digitizes, amplitude and phase modulates each of the three signals and generates four traces: A.C. current amplitude, magnetic field amplitude, A.C. current phase and magnetic field phase. The latter two traces are derived with respect to an A.C. voltage phase signal. Comparable baseline signals previously gathered for the valve are stored.

Abstract: A controller for controlling the operation of a motor operated valve combination, including a valve yoke, a valve stem, a valve disc, a valve seat and a motor operator having a motor and drive means interconnecting the motor to the valve stem for movement of the valve stem in a first direction to move the valve disc into engagement with the valve seat for closing the valve. The controller comprises a sensor for sensing forces experienced by the valve stem during valve closing and for generating related electrical signals. A first detector is employed for receiving the electrical signals from the sensor, for determining when the rate of change in the valve stem forces exceed a first predetermined limit and for generating an electrical signal when the first predetermined limit is exceeded.

Abstract: A monitoring system for use with a conventional actuator system which includes an actuator and control system. The monitoring system comprises a wiring harness including at least three and preferably five ring type current sensors, such as current transformers or Hall effect devices, which are permanently mounted on various leads associated with the control system. The sensors sense currents carried on the leads which are indicative of the state of control system switches connected with the leads. The sensors generate signals responsive to the currents and indicative of the switch states. Each of the sensors is spaced from and wired to a single electrical connector. The connector is adapted to removably mate with a complementary connector to simultaneously electrically couple the complementary connector with each wired sensor.

Abstract: An operating turbine monitor is described incorporating one or more acoustic sensors positioned next to a blade row of a rotor, an analog digital converter, a tachometer sensor at the rotor shaft, a memory, a synchronous averaging circuit, a subtractor circuit, and a comparator. The invention overcomes the problem of monitoring an operating tubine for order-related turbine blade vibration and for non order-related turbine blade vibration as well as for other turbine conditions.

Abstract: A monitor for torsional shaft vibration in an operating turbine is described incorporating two marks longitudinally spaced apart on the shaft, sensors longitudinally spaced apart by a predetermined distance for detecting each mark as it passes by the sensor, a timer for measuring the lapse time of rotation of each mark, and a subtractor. The invention overcomes the problem of accurately detecting, measuring and interpreting transient angular shaft vibration.

Abstract: Devices and methods for determining axial loads on a generally cylindrical member include a clamp portion removably attached by clamping to a portion of a generally cylindrical load-bearing member. The clamp portion of the device moves in response to diametral deformations in the clamped portion of the cylindrical member. A sensor is provided to sense movement of the clamp portion of the device in response to diametral deformations in the portion of the cylindrical member. The sensor generates signals related to the magnitude of the sensed movement and thus the sensed diametral deformations. The sensed movement may be bending in the clamp portion of the device or distance changes between parts of the clamp portion of the device. A signal storage device, which may also be a computer, stores the signals for real time or delayed determination of axial loading in the member.

Abstract: The present invention comprises a thrust actuated control for use in a motor operated valve having a motor operator including a motor drive, a stem nut coupled to the motor drive for rotation about an axis and a stem nut lock coupled to the motor drive for preventing axial movement of the stem nut. The valve includes a valve gate, a valve seat and a valve stem coupled to the valve gate, the valve stem threadingly engaging the stem nut for axial movement in a first direction upon rotation of the stem nut in a first direction to move the valve gate toward and into engagement with the valve seat and for axial movement in a second direction upon rotation of the stem nut in a second direction to move the valve gate out of engagement with and away from the valve seat.

Abstract: A strain sensor device is disclosed for attachment to a structural member for measuring strains experienced by the member along a strain axis. The strain sensor device comprises a tensile strain member secured to the structural member generally parallel to the strain axis. Two strain gages are secured to the tensile strain member, one of the strain gages being longitudinally oriented with respect to the strain member to experience longitudinal strain and the other of the strain gages being transversely oriented with respect to the strain member to experience Poisson strain. The two strain gages comprise a strain gage bridge circuit for generating electrical signals proportional to strains sensed in the structural member.

Abstract: A device for measuring and indicating the forces on a valve stem over at least a portion of the valve strokes is comprised of a strain sensor secured to the valve yoke for sensing strains experienced by the valve yoke. The sensed strains are proportional to the forces on the valve yoke and are equal but opposite to the forces on the valve stem. The strain sensor generates electrical signals proportional to the forces on the valve stem. In one embodiment, a second strain sensor is secured to the valve operator for sensing strains experiences by the valve operator and for generating proportional electrical signals. A display, electrically connected to the strain sensors, is provided for receiving the generated electrical signals and for indicating the forces on the valve stem and the forces on the valve operator.

Abstract: A device is disclosed for in situ detecting of axial motion of a generally cylindrical member in which both ends of the member are unavailable for the installation of a prewound coil. The device comprises a predetermined length of generally flat multiconductor cable. A first connector component is secured to one end of the cable, the first connector component having a plurality of electrical contacts, the number of contacts being at least two greater than the number of conductors of the cable. A second connector component is secured to the other end of the cable, the second connector component having a plurality of electrical contacts, the number of contacts being at least two greater than the number of conductors of the cable.

Abstract: A device for measuring and indicating the forces on a valve stem over at least a portion of the valve strokes is comprised of a strain sensor secured to the valve yoke for sensing strains experienced by the valve yoke. The sensed strains are proportional to the forces on the valve yoke and are equal but opposite to the forces on the valve stem. The strain sensor generates electrical signals proportional to the forces on the valve stem. A display, electrically connected to the strain sensor, is provided for receiving the generated electrical signals and for indicating the forces on the valve stem. A system for evaluating the performance of a valve and valve operator also utilizes the yoke strain sensor in combination with other sensors, including a valve stem motion sensor, a spring pack motion sensor, a motor current sensor and, possibly, a stem strain sensor, as well as an indicator of the condition of torque and limit switches.

Abstract: A method and apparatus for detecting and identifying one or more excessively vibrating blades of the rotating portion of a turbomachine utilizing analysis of the characteristic Doppler waveform that results as the rotating, vibrating blade passes a fixed sensor. The acoustic energy in the vicinity of the rotating portion of the turbomachine is sensed to generate a composite electrical signal representative of the broadband acoustic spectrum. Then, through both time domain and frequency domain signal manipulations, the undesirable noise components of the composite signal are removed. The resulting signal is then displayed to reveal the characteristic Doppler waveform of the blade vibrations, which may be analyzed to indicate the location of the excessively vibrating blade as well as its relative vibration amplitude. Changes in the latter with time indicate the initiation or propagation of a blade crack.