Dmar Engineering, Inc.

Zhiming Huang

Dagang Zhang

Yongtian Kang

Quan Yuan

Apparatus and methods related to pipeline freespan support are described. For example, some embodiments may contain an upper structure, which contains at least four legs connected to one another by a number of bracing members, and a number of attachment points through which the upper structure can be lifted, and a lower structure, which contains at least four posts that can be connected to, and disconnected from as needed, the four legs of the upper structure, two spaced mud mats on which the posts stand, and at least two horizontal arms that can be attached to the posts, rotate about the posts, connect to and be locked with the posts on the other mud mat, and be lifted to an appropriate height to provide suitable support at the pipeline freespan location.

Pipeline freespan support

Apparatus and methods related to low cycle fatigue testing are described. For example, some embodiments may contain a control box, two fitting connections, a pressure gauge, a plurality of clamps, a plurality of hydraulic cylinders, a plurality of control cables, and a strain gauge, for testing the low cycle fatigue properties of a testing specimen, for example, a steel tube umbilical.

Low cycle fatigue testing

Apparatus and methods related to umbilical bend-testing are described. For example, some embodiments may contain a three-level support structure, umbilical terminal locker, bending machine, compression testing device, and stress-strain collection system, and may be used for the bending fatigue endurance test for umbilical samples.

Umbilical bend-testing

Apparatus and methods related to riser joint connection are described. For example, some embodiments may contain a central coupler, a plurality of reaction collars, collar stoppers, collar caps, and C-rings, for connecting riser joints.

Riser joint connection

Apparatus and methods related to damping testing are disclosed. For example, some embodiments may contain a testing platform supported on wheels and moveable by hydraulic cylinders, and two fasteners for fastening the testing sample, one fixed on the testing platform and the other moveable along the testing platform by another hydraulic cylinder, and may be used for the damping testing of slender structures such as umbilicals and flexibles used in oil and gas underwater field development.

Damping testing

Apparatus and methods related to fatigue testing are described. For example, some embodiments may contain a terminal fixer, a terminal support, a bending machine, and a stress-strain collector, and may be used for testing fatigue properties of offshore pipes, risers and their connectors. Some embodiments may be used to apply extruding, twisting and high frequency bending to the testing sample during one testing period, so that the various fatigue properties of the testing sample can be obtained.

Fatigue testing

A hydraulic power unit, a flow meter, and a pressure gauge couple to a first end of a tube under testing. The hydraulic power unit provides an inlet pressure to move a testing fluid through the tube. The flow meter measures a flow rate of the testing fluid and the pressure gauge measures the inlet pressure. An accelerometer measures sound and vibration of the tube. A reservoir couple to an outlet of the tub and an inlet of the hydraulic power unit. The reservoir supplies the testing fluid to the hydraulic power unit and collects the testing fluid from the tube. Hoses interconnect the components in a closed loop that reuses the testing fluid. By analyzing the flow rate, it is determined if an obstruction exist in the tube. By analyzing the inlet pressure and the sound and vibration of the tube, a location of the obstruction is determined.

Flow rate testing to locate tube obstruction

Apparatus and methods related to catenary riser testing are described. For example, some embodiments may contain a ground platform, elevated deck, a catenary-shaped testing sample, a fixed clamp on one end of the testing sample and a rotatable clamp on the other end of the testing sample, and a plurality of hydraulic cylinders for controlling the vertical and horizontal positions and motions of the elevated deck and the positions and rotations of the rotatable clamp, for analyzing the characteristics of the testing sample, such as its touchdown point dynamic motions and stresses.

Catenary riser testing

Apparatus and methods related to umbilical buckling testing are described. For example, some embodiments may contain two damps, a plurality of test fittings, one or more pressure gages, a hydraulic cylinder, and a testing platform, and may be used for testing the umbilical buckling behavior and capacity of an umbilical testing sample.

Umbilical buckling testing

Apparatus and methods related to bending testing are described. For example, some embodiments may contain a clamp with pivot pin, pellet, tensioning device, and supporting platform, which can be used for testing the bending characteristics, such as bending stiffness, of a testing sample, which can be slender structures such as umbilicals, flexibles, and rigid pipes.

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Missouri City, TX, United States of America

Zhiming Huang