Chevron U.s.a. Inc.

California Institute of Technology

Hailing An

Baha Tulu Tanju

Darmindra D Arumugam

Robert Kwan Meng Seah

Thomas Edward O'Donnell

Omid Oujani

George Siappas

Ashish Karamchandani

James Nileshwar

Chukwuemeka U Emecheta

A method for evaluating performance of a choke valve includes collecting baseline performance data for the choke valve during a first time period; establishing a relationship between a flow area and positions of the choke valve for the first time period; collecting measurements of parameters associated with the choke valve during a second time period; generating a predicted flow area of the choke valve during a second time period;, generating an estimated flow area through the choke valve during the second time period using the relationship established during the first time period; comparing the estimated flow area with the predicted flow area for the second time period; and determining that the performance of the choke valve is no longer within the range of acceptable performance values when a difference between the estimated and predicted flow areas for the second time period falls outside a range of threshold values.

Evaluating choke valve performance during subterranean field operations

Magneto-quasistatic signals may be used to enable under-liquid communication between devices. A magneto-quasistatic signal transmitter of an under-liquid device may transmit a magneto-quasistatic signal conveying communication data through liquid. A magneto-quasistatic signal receiver of another under-liquid device may receive the magneto-quasistatic signal and extract the communication data from the magneto-quasistatic signal. The under-liquid device that received the magneto-quasistatic signal may use the communication data, store the communicate data, and/or relay the communication data (e.g., to another under-liquid device, to an above-liquid device) using another magneto-quasistatic signal.

Under-liquid communication using magneto-quasistatic signals

Magneto-electric quasistatic (MEQS) field may be used to track positions of persons and/or objects inside metallic environments. A magneto-electric quasistatic field generator may generate a magneto-electric quasistatic field inside a metallic environment. A magneto-electric quasistatic field detector inside the metallic environment may detect the magneto-electric quasistatic field and generate output signals conveying characteristics of the magneto-electric quasistatic field. The relative position of the magneto-electric quasistatic field detector with respect to the magneto-electric quasistatic field generator may be determined based on the output signals. The position of the magneto-electric quasistatic field detector/generator and/or the position of a person/object carrying the magneto-electric quasistatic field detector/generator may be tracked using the relative position of the magneto-electric quasistatic field detector with respect to the magneto-electric quasistatic field generator.

Position tracking inside metallic environments using magneto-electric quasistatic fields

A magneto-quasistatic field may be used to align hydrogen of materials within a structure and/or to disrupt the alignment of hydrogen of materials within the structure. Realignment of the hydrogen after the disruption may cause emission of energy from the hydrogen. The characteristic(s) of the energy may be detected and used to generate image(s) of interior portion(s) of the structure.

Imaging inside a structure using magneto quasistatic fields

An apparatus and method for providing a controllable supply of fluid, and optionally power and/or communication signals, to a subsea equipment are provided. The fluid may be a water-based fluid, oil-based fluid, or chemicals. The apparatus includes a reservoir disposed on a seabed for storing a supply of fluid for delivery to the subsea well equipment. A subsea pumping device is configured to receive the fluid from the reservoir, pressurize the fluid, and deliver the pressurized fluid to an accumulator of a hydraulic power unit disposed on the seabed. The hydraulic power unit can store the pressurized fluid and control an output of the pressurized fluid to the subsea well equipment, thereby providing a subsea fluid source for the subsea equipment.

Apparatus and method for providing a controllable supply of fluid to subsea well equipment

Accurate, dependable methods for analyzing operational parameters of subsea control systems and diagnosis/prediction of failures are provided, in particular, methods for detection of leaking and/or clogging in hydraulic control system using recorded pressure signals and evaluating response communication strength (signal amplitude) of field equipment from, for example, subsea control systems. Prediction of failure(s) allows an opportunity to prepare for intervention to minimize the impact of failure before failure occurs, for example, by ordering equipment, tools and/or scheduling an intervention vessel. Similarly, diagnosing a failure drastically shortens the intervention time.

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Houston, TX, United States of America

Hailing An