Patent ID: 12241873

DETAILED DESCRIPTION

The present disclosure sets forth a novel system designed to permit testing of samples under a combination of conditions, including pressures, temperatures, bending loads, and tensile (or compression) loads. The system may permit large samples to be tested, including actual production parts, particularly elongated parts and components. In particular, the system is well adapted for testing of tubular products such as those used in oil and gas exploration, well drilling, and mineral production. Environments encountered in subterranean and subsea environments may be simulated by the filling of any desired fluid in the system, and application of pressures and temperatures that may be present. Under such conditions, in combination, mechanical loading may be applied, and data taken to analyze performance of the sample.

Turning to the drawings,FIG.1illustrates an exemplary testing system10that permits combined condition testing of elongated samples. The system has an elongated chamber/autoclave12that itself comprises a fixed chamber assembly14and an elongated movable or flexible assembly16. The two assemblies are joined via a sealed flange but may be separated for loading of samples, inspection, maintenance, and so forth. The fixed chamber assembly14has a closed end (not separately shown), and a heavy cylindrical wide wall that can contain pressures of up to at least 35,000 PSI. The flexible assembly16can contain similar pressures, but can be flexed under the influence of loading systems as discussed below. Both wetted parts (basically the internal and sealing surfaces) of both assemblies are made of a metal capable of resisting corrosion from a wide range of fluids that may be loaded in the chambers. Metals presently contemplated include, for example, specialty steels, stainless steel, nickel alloys, and titanium alloys.

The chamber assemblies14and16are secured within a framework18that holds them in place, and that provides an integral support structure to resist loading applied to the chambers and sample. In the illustrated embodiment, the framework18comprises side members20and a truss or reinforcing structure22. Any desired support structure may be provided, however, and it may take on any desired shape. In the illustrated embodiment, the side members20extend between a fixed end structure24and an opposite end structure26that allows for movement during application of bending loads as discussed below. These parts may be made of any suitable production stock, such as steel. A load extension28allows for mounting of the mechanical loading components. Some or all of these structures may be at least partially dismountable, and could be covered by guards or shields (not shown) during testing. In the load extension28a sliding thrust plate30is provided for application of mechanical loads as discussed below.

The system10includes systems, or subsystems that allow for the desired test conditions, all of which may be separately controlled under the direction of a centralized or common control and data collection system. In the embodiment ofFIG.1, for example, an internal pressure system32is coupled to one or both of the chamber assemblies, and allows the application of desired pressures to the sample positioned in the chambers. It is contemplated that many environments of interest may be simulated by filling the chambers with gasses, liquids, or a combination of these. For example, in the case of subterranean and/or subsea environments, the chambers may be filled with, for example, seawater, simulated seawater, corrosive liquids and gasses, and so forth. In general, it is anticipated that once loaded and sealed in the chambers, such fluids may be subjected to positive pressures (i.e., higher than atmospheric) by one or more pumps or compressors included in the internal pressure system32. The internal pressure system32may also allow for purging the chambers. Moreover, although positive pressures may be of particular interest, the system may be capable of applying negative pressures (i.e., partial vacuum pressures) by use of one or more vacuum pumps. Presently contemplated pressures up to on the order of 35,000 PSI may be applied by the internal pressure system.

A thermal system34is provided that allows for the temperature of the chambers to be raised (or lowered) to desired test conditions. The thermal system may heat (or cool) the fluid in the chambers, or the internal volume surrounding the sample, or parts of the chamber structures, or some or all of these. In a presently contemplated embodiment, desired temperatures are provided by a thermal jacket surrounding the chamber, or internally via fluid feeds through a port of the chamber from a fluid heating or cooling system, having temperature ranges on the order of approximately OF (or lower) and up to 450 F or higher.

Mechanical loading of the sample may include bending loading, tensile (or compressive) loading, or any combination of these. As illustrated, a bending load system36applies bending loading by lateral movement of the flexible chamber assembly16. In particular, in this embodiment a hydraulic cylinder38may be extended and retracted to move the sliding thrust plate30. The cylinder is powered by pressurized hydraulic fluid from a hydraulic power unit40applied via appropriate valving42(e.g., directional control valving). Control circuitry44allows for control of the valving, as well as pressures applied to the cylinder as needed for movement during testing. It may be noted that, owing to the geometry of the support structure, a range of lateral motion may be offered by the cylinder38and plate30. In a presently contemplated embodiment, for example, lateral movement on the order of approximately =/−2 ft. or more may be applied to provide bending over a sample length of 6 ft. or more (e.g., up to approximately 30 ft. Of course, other lateral ranges and lengths may be accommodated by appropriately dimensioning the flexible chamber assembly and framework.

Further, a tensile draw system46allows for application of tensile loads up to approximately 5,000 lbs. to approximately 250,000 lbs. and beyond. The components of system46may be similar to those of the bending load system36, so those parts are not separately illustrated in the figure. In fact, in some embodiments, the two systems may be at least partially combined so that the same hydraulic power unit and valving allow for application of tensile loads to the sample (e.g., by retraction of a tensile loading hydraulic cylinder). It may also be noted that the system may be designed for application of compressive loads by slight modification of the illustrated arrangement (e.g., by capture of the thrust plate30so as to allow for extension of the cylinder of system46). It may be further noted that both bending and tensile loads may be applied at the same time, or in any sequence. In the illustrated embodiment, the load-applying cylinder of the tensile loading system can move along with the sliding thrust plate30as it is displaced laterally by cylinder38. In some embodiments, the framework, and particularly the components of the end structure26may be designed to allow for straight travel paths of the thrust plate (as illustrated) or arcuate travel paths, with the tensile load being applied uniformly or in any alternative way to the sample. For example, for straight travel paths, hydraulic pressures (and resulting forces) of the tensile system46may be altered as the thrust plate is displaced laterally to maintain the desired tensile load.

A control and interface system48is illustrated that allows for both control of the various subsystems, and for collection of data during tests. As illustrated, a control system50is provided for overall control of test conditions, protocols, presentation of data, and so forth. While this control and oversight may be separated for each subsystem, the illustrated common control allows for integrated control of application of complex combinations of loads. In practice, the control system50may comprise an appropriately programmed computer. A data collection component52cooperates with the subsystems and any instrumentation of the sample for logging tests, data entry by a test operator, and so forth. A data analysis component54allows for analysis of the test data (e.g., signal conversion, scaling, presentation of combined test conditions, graphical or numerical analysis, etc.). Finally, a human machine interface or HMI56is provided for permitting operator inputs, oversight, and control of the process. The HMI may include, for example, one or more computer monitors, input devices, and so forth.

FIG.2illustrates exemplary details of how the bending and tensile loading components may be supported and connected to the plate30and framework. As shown, an attachment structure58(e.g., a clevis, tang, or other connection point) allows for attachment of the end of the shaft of the bending load cylinder. Another attachment structure60allows for connecting the tensile load cylinder (while permitting lateral movement of the tensile load cylinder with the plate30). In this embodiment, the thrust plate30slides along rails62fixed to the end structure26.

As noted above, a range of elongated samples may be tested in the system, including solid and tubular structures, such as drill pipe, production pipe, and so forth in oil and gas applications. The instrumentation of such samples may take any desired form, including by way of example, strain gauges.FIG.3shows an instrumented sample64loaded in the system but before final assembly of the chambers around the sample. Couplings or mounting ends66permit holding the sample in place and application of the mechanical loads. In this example, a series of instruments68(e.g., strain gauges) are secured to the sample, and conduits70allow for application of any signals to the instruments, as well as collection of resulting signals (for later conversion and analysis). It should be noted that in presently contemplated embodiments the couplings may be eliminated, and useful shapes, such as tapers may be employed for parts of the system.

FIG.4is an overall view of the system discussed above. As shown, the subsystems32,34,36and46are placed in data communication with the control system48, as are the sample instruments. Of course, various data busses, converters, and interface circuitry and devices may be involved in such connections, as will be readily apparent to those skilled in the art. The control system48, for its part, will include input signal interface circuitry72, such as for performing such operations as receiving, converting, conditioning, and filtering of the received signals and data. Similarly, output signal interface circuitry74is provided for creating and applying control signals to the subsystems by operations such as amplification, conversion, scaling, and so forth. The interface circuitry is coupled to processing circuitry76, such as one or more digital signal processors, microprocessors, and the like (along with its associated components, such as converters, power supplies, and so forth). Memory circuitry78is provided for the processing circuitry and may include both volatile and non-volatile memory as needed for the testing envisaged. In practice, the memory circuitry will store coded instructions and programming that is executed by the processing circuitry based on test protocols, operator inputs, configuration parameters of the subsystems, and so forth. The memory circuitry may also store raw and processed data and files resulting from tests performed.

FIG.5illustrates exemplary logic80that may be followed in the setup and testing of samples in the system described above. As illustrated, in a first operation82the sample is instrumented. As noted, this may involve the application of strain gauges or any other useful instruments to the sample, and these are coupled to any transmission wiring (or wireless systems) for reading signals from the instruments during tests. The sample is then positioned in the autoclave (i.e., the chamber assemblies) and secured for application of mechanical loads. Once sealed in the device, then, the chambers may be filled and/or purged with the desired fluid, as indicated by operation86. It should be noted that where desired, the interior of a tubular sample may be filled with one fluid while a different fluid surrounds the outer surface of the sample to simulate actual use conditions. The subsystems involved in the prescribed test protocol may then be secured or connected to the chamber(s) and sample, as indicated at operation88. In some protocols, all of the subsystems will be called for, though in general the process allows for fewer than all of them to be prescribed and used. At operation90the testing is performed, such as by application of desired pressures, temperatures, tensile and bending loading. Of course, these may be applied in various combination, cycles, rates, and so forth as called for by the test protocol stored in the memory circuitry, and modified by any operator input parameters. At operation92data is collected. In contemplated embodiments, this will include logs of all of the desired test parameters (e.g., pressures, temperatures, and mechanical loads) that may be timestamped to permit correlation with one another. Finally, at operation94the data is analyzed, such as by calculations of elongation, stresses, strains, graphical presentation of applied loads/conditions and the resulting sample performance, and so forth.

While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.