Williams P.,Louisiana State University |
Liakat M.,Louisiana State University |
Khonsari M.M.,Louisiana State University |
Kabir O.M.,Cameron International Inc.
Materials and Design | Year: 2013
An in situ technique for predicting the Remaining Fatigue Life (RFL) of metal specimens is used to study welded joints. Uniaxial tension-compression tests were carried out using welded and heat treated tubular specimens of carbon steel 1018. An infrared camera was used to capture thermographic data from the specimens during testing. Short-time excitation (STE) tests were used to determine the slope of temperature increase at several points throughout the fatigue life to characterize the damage. Verification tests were carried out at different stress levels to study the accuracy of the RFL prediction method on welded specimens. The presented results show good agreement between the predicted and experimentally measured fatigue lives. However, tests with welded specimens containing flaws showed significantly shorter fatigue lives. The prediction method discussed in this paper does not characterize the RFL of flawed specimens. © 2013 Elsevier Ltd.
Nathan M.L.,University of Texas at Austin |
Nathan M.L.,Cameron International Inc. |
Dyson T.E.,University of Texas at Austin |
Dyson T.E.,General Electric |
And 2 more authors.
Journal of Turbomachinery | Year: 2014
There have been a number of previous studies of the adiabatic film effectiveness for the showerhead region of a turbine vane, but no previous studies of the overall cooling effectiveness. The overall cooling effectiveness is a measure of the external surface temperature relative to the mainstream temperature and the inlet coolant temperature, and consequently is a direct measure of how effectively the surface is cooled. This can be determined experimentally when the model is constructed so that the Biot number is similar to that of engine components, and the internal cooling is designed so that the ratio of the external to internal heat transfer coefficient is matched to that of the engine. In this study, the overall effectiveness was experimentally measured on a model turbine vane constructed of a material to match Bi for engine conditions. The model incorporated an internal impingement cooling configuration. The cooling design consisted of a showerhead composed of five rows of holes with one additional row on both pressure and suction sides of the vane. An identical model was also constructed out of low conductivity foam to measure adiabatic film effectiveness. Of particular interest in this study was to use the overall cooling effectiveness measurements to identify local hot spots which might lead to failure of the vane. Furthermore, the experimental measurements provided an important database for evaluation of computational fluid dynamics simulations of the conjugate heat transfer effects that occur in the showerhead region. Continuous improvement in both measures of performance was demonstrated with increasing momentum flux ratio. © 2014 by ASME.
Gavanluei A.B.,Cameron International Inc. |
Mishra B.,Colorado School of Mines |
Olson D.L.,Colorado School of Mines
NACE - International Corrosion Conference Series | Year: 2013
Corrosion rate of a low alloy tempered martensite downhole tubular steel was studied at different temperatures and CO2 partial pressures using direct weight loss measurement. Experiments were carried out in a high pressure high temperature autoclave. CO2 partial pressures of 40 (276), 80 (552), 160 (1103), and 320 (2206) psi (kPa) were examined at temperatures 25, 40, 50, and 75 °C. A linear trend between corrosion rate and CO2 partial pressure was observed at different temperatures and increasing CO 2 partial pressure increased the slope of the lines. In addition, at constant CO2 partial pressure, increasing temperature increased the corrosion rate. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to study the corrosion products formed on the surface. At 50 °C and below, only iron and iron carbide were detected using XRD analysis, but, at 75 °C, in addition to iron carbide, iron carbonate was also detected. Formation of scattered iron carbonate crystals was studied using SEM. Finally, having the corrosion rate at different temperatures and CO2 partial pressures, the activation energy of the corrosion process was calculated using the de Waard Equation. © 2013 by NACE International.
Wood M.,Cameron International Inc.
GPA Annual Convention Proceedings | Year: 2011
The molecular sieve dehydration unit is an important process in any plant that uses natural gas as a feedstock. Molecular sieve dehydration is currently the process by which almost all water is removed from gas. The switching valves (gas in, gas out, regeneration in, regeneration out, pressuring and depressuring) are critical components in this process. A discuzssion covers selection of the proper valve type for use as a molecular sieve switching valve; common pitfalls; construction, start-up, and plant commissioning phases; common problem in the operation of switching valves; turnarounds, shutdowns, repair, and maintenance; and recommendations to extend the operating life on switching valves used in molecular sieve dehydration service. This is an abstract of a paper presented at the 90th Annual Convention of the GPA (San Antonio, TX 4/3-6/2011).
Citirik E.,Cameron International Inc.
Journal of Pressure Vessel Technology, Transactions of the ASME | Year: 2012
A comprehensive methodology is developed to understand and characterize the fracture behavior of circumferentially cracked boiler tubes in this study. Weld overlay is applied on the coal-fired boiler tubes in order to prevent the degradation of corrosive and erosive environment that the boiler tubes are exposed to in the power plants. Finite element modeling and analysis are employed for all of the computations including steady-state and transient stress intensity factor (SIF) calculations in this study. Circumferential cracking has been one of the failure modes in waterwall boiler tubes, which results in high maintenance and replacement costs. Thermomechanical stresses and corrosive environment are basically the two remarkable contributors that bring about this failure mode. The former one is investigated and quantified in this study in order to explain the fracture behavior of weld overlay coatings during the power plant operation. Periodic soot blowing operations cause cyclic transient thermomechanical stresses on the weld overlay coating that results in crack propagation and fatigue failure. Three-dimensional fracture analysis of circumferentially cracked boiler tubes is examined using enriched finite element method in this study. Transient temperatures and thermomechanical stresses are computed using ANSYS for five different periodic crack spacing values (h), which are 2, 4, 6, 10, and 20 mm in the axial direction. 3D fracture analysis was performed, and stress intensity factors were computed using FRAC3D, which is Finite Element Analysis (FEA) software developed at Lehigh University. The maximum stress intensity factor is obtained at the deepest penetration of the crack in the model which has the largest periodic axial crack spacing, h 20 mm. The stress intensity factors due to welding residuals decrease as the axial crack spacing, h, decreases. The FEA methodology developed in this research would provide the engineers with the ability to understand the fracture problem and predict component life and improve the reliability of the weld overlay coated boiler tubes utilized in the power plants. © 2012 American Society of Mechanical Engineers.
Bhatnagar M.,Cameron International Inc. |
Sverdrup C.J.,Cameron International Inc.
Proceedings of the Annual Offshore Technology Conference | Year: 2014
The Cameron TST-CFU® is the next generation compact flotation unit that uses gas flotation and additional centrifugal forces to separate and remove hydrocarbons as liquid and gas, aromatic compounds, hydrophobic substances and small solid particles from produced water. The technology uses special fixed internals for mixing of gas and oil through several stages within one vessel. This next generation compact flotation unit is capable of handling high inlet oil concentrations and providing lower outlet OIW concentrations (less than 10ppm). This compact flotation technology requires less equipment, has a lower weight, smaller footprint, is less dependent on chemicals and can potentially replace multiple produced water treatment technologies. This paper will cover some of the test results from pilot testing conducted on this next generation compact flotation unit. Copyright 2014, Offshore Technology Conference.
Cameron International Inc. | Date: 2010-06-15
In at least some embodiments, an apparatus includes a hydraulic directional control manifold and a plurality of electric piezopumps. The apparatus also includes an electric piezopump controller that operates the plurality of electric piezopumps in varying combinations to provide generation and directional control of hydraulic power to linear hydraulic actuators using localized closed-loop hydraulic fluid.
Cameron International Inc. | Date: 2010-06-15
In at least some embodiments, a system includes a first remote tool. The system also includes a variable frequency drive (VFD) coupled to the first remote tool, wherein the output of the VFD powers the first tool and wherein at least part of the VFD is in situ with the first remote tool.
Cameron International Inc. | Date: 2012-03-02
A system including, a first component of a mineral extraction system, and a first radio frequency identification (RFID) module coupled to the first component, wherein the first RFID module comprises first component data relating to the first component, and first location data relating to a first location of the first component.
Chen X.,Cameron International Inc. |
Bartos J.,Cameron International Inc. |
Salem H.,Cameron International Inc. |
Zonoz R.,Cameron International Inc.
Offshore Technology Conference, Proceedings | Year: 2016
This study demonstrates the characteristics of elastomers with excellent sealing performance at both low and high temperatures, as required by subsea wellheads and blowout preventers (BOP). Elastomers with excellent rapid-gas-decompression (RGD) resistance and high temperature sealing normally have limited low temperature sealing performance due to their high modulus characteristics. It is, therefore, challenging to identify elastomers with RGD resistance that have both high and low temperature sealing performance. This study investigates the glass transition temperature (Tg) and high pressure compression stress relaxation behavior of various elastomers at low temperatures, and presents their influence on low temperature sealing performance under test conditions of static as well as cycling pressure/temperature. Additionally, the effect of high pressure N2 test gas on elastomer sealing performance was investigated. Copyright 2016, Offshore Technology Conference.