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As a typical coating material for fire protection and heat insulation of offshore platforms, the intumescent fireproof coating can slow down the flame and heat propagation rate, thus it can gain time for fire fighting and personnel escape. However, the effective implement of the intumescent fireproof coating is subject to the quality control of the fireproof coating during the construction process. Therefore, this article systematically describes the key points and requirements of quality control in the construction process of intumescent fireproof coating on offshore platforms so as to provide reference for the construction quality control of fireproof coating in the field of marine engineering. [ABSTRACT FROM AUTHOR]

Objective The aim is to solve the problem that a triethylene glycol(TEG) dehydration unit on an offshore platform could not meet the dehydration requirements. Methods Based on the actual production data, the simulation analysis of the process system was carried out by HYSYS software to found out the causes of the operation problems of the system. Results The high water content in the natural gas at the inlet of the dehydration tower is the main factor affecting the effect of the dehydration system. Both the inlet filter separator and the reboiler should be considered in the transformation plan. Combined with the actual situation of the platform, the transformation scheme was finally determined to replace the inlet filter separator filter element and the electric heater of reboiler. After the transformation, the dew point of dry gas water at gauge pressure of 5.2 MPa was reduced from 6 ℃ to -23 ℃ which achieved the expected effect and reserved the operation space for subsequent expansion. Conclusions The reason why the processing capacity of the TEG dehydration unit on the offshore platform cannot reach the design value might be that the performance of the inlet filter separator was not up to standard, which leads to the excessive water content of the natural gas at the inlet of the dehydration tower. It was suggested that the processing index of the inlet filter separator should be strictly controlled during the process design of the TEG dehydration unit, and the TEG dehydration device should be matched according to the treatment index of the inlet filter separator. [ABSTRACT FROM AUTHOR]

Copyright of Metal Working (1674-165X) is the property of Metal Working Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Under the background of rapid digital transformation in the oil industry, in order to improve the development efficiency of offshore platform simulation system, this paper proposes a simulation method of offshore platform based on virtual reality technology. This method completes the rendering and output of the screen by using a physics based rendering framework; Develop adaptive tools to produce a large amount of repetitive content such as sensor range and handrail; The external general file driven editing mode, such as Excel, allows users to directly modify some information. The actual project application shows that the above methods can reduce more than 90% of the screen rendering time, improve the production and modification efficiency of repetitive work, and improve the flexibility and robustness of the system. This method provides reference for the subsequent simulation project production and helps the digital construction of offshore oil. [ABSTRACT FROM AUTHOR]

Aimed at the operating failure problem of a shaft end mechanical seal of the oil-gas multiphase pump on the offshore platform, the causes were analyzed, and the structure was improved. Through the performance test of the improved mechanical seal, the change of sealing performance with pressure the wear condition of sealing end face under different spring specific pressure conditions were compared and analyzed, and the change of sealing performance with pressure and rotational speed under different end face widths was compared and analyzed. The results show that reducing the spring specific pressure can slightly reduce the friction power of the seal end face, but it will increase the risk of leakage, and reducing the end face width can effectively improve the sealing performance under poor lubrication conditions. The optimal design parameters of the seal were determined, and the 100 h qualification test of the domestic sealing prototype was carried out. The stability of the friction power of the sealing end face and the leakage index during its operation were examined. The experimental results show that the friction power of the improved sealing end face is basically stable, with small fluctuations, and the leakage meets the standard index requirements. This verifies the rationality of the improved sealing structure, the effectiveness and the adaptability of operating conditions of optimizing design parameters. [ABSTRACT FROM AUTHOR]

In the course of towing of offshore platform, it is of great significance to calculate the towing resistance ahead of time and select the main tugboat with proper power for towing safety. In this paper, the calculation formulas or recommended methods for towing resistance of mainstream classification societies were investigated, and a CFD/AQWA finite element numerical simulation was conducted for the typical jack-up offshore platform in Shengli Petroleum Engineering Company.Based on the comparative analysis of the results, a suitable model for the calculation of towing resistance of platforms in domestic waters was optimized, and a suitable towing factor of safety was proposed.

Using the crude oil ultrasonic treatment experimental device, the effects of ultrasonic action time, action temperature, ultrasonic frequency, ultrasonic power, and crude oil viscosity changes on the viscosity reduction characteristics are analyzed. The results show that when the temperature is lower than 70 °C, the viscosity of crude oil is significantly reduced by ultrasonic treatment. When the temperature is higher than 70 °C, the viscosity of crude oil after ultrasonic treatment increases, mainly due to the effect of the cavitation threshold. With the increase of ultrasonic action time, the viscosity reduction of crude oil after ultrasonic treatment increases first and then decreases, which is mainly related to the thermal effect of ultrasound. When the ultrasonic power increases, the time required to achieve the same ultrasonic cavitation effect becomes shorter, and the optimal ultrasonic action time becomes shorter. With the increase of ultrasonic power, ultrasonic viscosity reduction first increases and then decreases, and there is a critical optimal ultrasonic power. The viscosity reduction effect of ultrasonic treatment is better for crude oil with viscosity ranging from 500 mPa ⋅ s to 1 081 mPa ⋅ s at 50 °C. [ABSTRACT FROM AUTHOR]

ObjectiveA string-type mooring system is proposed for the permanent berthing demands of special offshore platforms. So it is necessary to study the hydrodynamic performance of the berthing platform using this mooring system to verify its adaptability to the permanent berthing demands.MethodsBased on the three-dimensional potential flow theory, a numerical model of the platform berthed alongside a terminal wharf is established using the boundary element method, and the frequency domain numerical simulation of the moored platform at different tide levels is carried out. Two mooring systems, i.e., string-type and traditional dock mooring, are used to simulate the hydrodynamic performance of the platform in the time domain under extreme wave conditions, and parameterized analysis is conducted to analyze the influence of different tide levels on the motion response of the platform.ResultsBy providing omni-directional restoring force, the string-type mooring system strengthens the rotational motion limitations of the platform, greatly reduce the most violent rolling motion, transfers the energy of environmental load to translational motion, and further strengthens the restriction of the overall motion of the platform; the motion range of the platform is balanced, stable and controllable; and the effects of the system on the motion limit of the platform are less affected by the change in tide level.ConclusionCompared with the traditional mooring system, the string-type mooring system is more suitable for the permanent berthing of special offshore platforms.

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Numerical simulation of typhoon is conducted based on the YanMeng wind field model and the results are compared with the measured data. The feasibility of the wind field model in the southeast coastal engineering sea area of China is verified. Afterward, the CMA's tropical cyclone best-track dataset is statistically analyzed to fit the typhoon key parameters for probability density distributions. Monte Carlo simulation method is used to simulate the extreme wind speed series of typhoon in the project sea area in 1000 years, and the extreme wind speed once for 50 years is calculated according to Gumbel distribution. It is found that the YanMeng wind field model simulation effect is good, and the results could be used as a reference basis for the structural design of coastal offshore platforms. [ABSTRACT FROM AUTHOR]

The superstructures of offshore platforms are usually complex in shape, and wind tunnel test is the most reliable method to obtain the wind loads. Few researches about the procedures of uncertainty analysis (UA) and key points have been conducted, and the influences of error sources are not clear. The UA of an offshore platform wind load tests is first performed based on the International Towing Tank Conference (ITTC) recommended procedures. According to the wind load test procedure of the offshore platform, the uncertainties due to many error sources are analyzed. In order to obtain the remark of all error sources and propose the approach of reducing uncertainties, error sources are evaluated and graded. The results show that the wind profile, the accuracy of the model, the air pressure measurement, and the balance measuring state have a great influence on wind load coefficients, which contribute to 96.13% of the combined uncertainty. The uncertainties can be effectively reduced by model simplification, high quality wind profile, high precision air pressure measurement, and stable measurement state.

A method for constructing a novel offshore platform was proposed. Based on the cooperative control of multiple unmanned vessels, a self-assembling platform was realized, which could be reconfigured into different shapes according to requirements. A docking controller was designed to realize the docking of two modules. A connecting rod and electromagnetic forces were adopted to complete the docking and reduce the difficulty. Besides, a test site was constructed using the conditions of pool, and a model test was performed to verify the functions of the proposed self-assembling platform. The results show that the design can realize the docking of any unmanned vessel. Compared with the single platform, this self-assembling platform can perform more complex tasks, whose decentralized design makes it more flexible and reliable.

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problem of increasing the volume of polymer injection system on offshore platform due to the long dissolution time of hydrophobically associated polymer, a high gravity instant dissolution device was developed・ The effects of high gravity factor on polymer dissolution time and the properties of target solution were studied by laboratory experiments・ The results show that with the increase of high gravity factor, the dissolution time of hydrophobically associated polymer AP-P4 gradually shortens, the high gravity factor increases from 0 to 1 298, and the basic dissolution time shortens from 80 min to 40 min; after Wuyin shearing, the viscosity of the target liquid first gradually decreases and then tends to be stable, and the resistance coefficient and residual resistance coefficient gradually decrease. [ABSTRACT FROM AUTHOR]

Copyright of Energy Chemical Industry is the property of Energy Chemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas & Oil is the property of Editorial Department of Natural Gas & Oil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives This paper studies the feasibility of the vibration isolation structure loop which is used to reduce the average vibration level of deck structures and to block the transmission of low-frequency vibration of deck structures.Methods The influence of forms and section parameters of vibration isolation structure loop on the low-frequency vibration transmission of deck and its adjacent bulkhead structure is explored by using numerical prediction method. By comparison, the form of vibration isolation structure loop with better vibration isolation effect is obtained. On this basis, the section parameterization of vibration isolation structure loop is carried out, and a better design scheme of deck structure with low-frequency vibration isolation is proposed. Results The results show that when the vibration isolation structure increases the total weight of the main engine room by no more than 5%, a rectangular multi-stage vibration isolation structure loop with the same mass has a better vibration isolation effect than other vibration isolation structure loops. For vibration isolation structures with a width of not less than 50 mm, when 500 mm is selected as a relatively optimum height and the relatively narrow hollow square steel is selected, the effect of reducing the average vibration level of deck and adjacent bulkhead structure is improved. Conclusions This research provides new insight relating to the design of low-frequency vibration isolation of the deck structures on offshore platforms.

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Petrochemical Universities / Shiyou Huagong Gaodeng Xuexiao Xuebao is the property of Journal Editorial Department Of Liaoning Shihua University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Petrochemical Universities / Shiyou Huagong Gaodeng Xuexiao Xuebao is the property of Journal Editorial Department Of Liaoning Shihua University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objectives] As one of the key marine equipment technologies,drag chains can provide protection for pipelines on offshore platforms. In order to study the topological relationship and structural strength of drag chains,we take one large drag chain as the research object.[Methods] First,according to the articulated relationship between the inner chain and outer chain,as well as the geometric dimension relationship between the articulated hole and circular arc groove of the inner chain plate,the topological relationships of drag chain are analyzed. The factors,rotation angle and pitch affecting the gyration radius of the drag chain are then acquired. Next,we adopt ANSYS Workbench to analyze the structural strength of the drag chain and obtain its structural response in an unloaded state. On this basis,we retain the original boundary conditions and increase the material density to simulate the stress state of a loaded drag chain,and the ultimate bearing capacity of the drag chain is acquired.[Results] The results show that the articulated shaft at the turning of a drag chain bears the greatest stress.[Conclusions] The findings of this paper show that drag chains are reliable in their use on offshore platforms.

Due to long-term used in the harsh environment,the functional degradation of the FPSO crane such as corrosion,fatigue crack,local failure occurred. The functional degradation could affect the normal use of the FPSO crane. According to the actual surveying data,the finite element model of the FPSO crane has been established by finite element software Ansys. The stress of high stress area has been tested according to the stress distribution of the FPSO crane. The calculation results of Ansys have been compared with the test data. The errors between calculation results and test data are in 14%,except of point 1941.The stress value of the most dangerous area is 247. 96 MPa,which is less than the allowable stress of the crane. Thus the strength requirement is satisfied. The relation between stress of key area of crane and the angle β of lifting has been analyzed. When the weight of lifting is close to the maximum working load,the working condition of β > 15°is preferred.

Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At present, trawl fishing as a traditional method is widely used in shellfish harvesting at home and abroad. However, using this method to catch the scallops has many disadvantages, such as huge energy consumption, high labor intensity, and poor fishing efficiency, which have become the key questions to restrict the sustainable development of marine fishing industry. Therefore, it’s very worth researching alternative scallop fishing equipment to meet the requirements of green development. The offshore scallop capture equipment is made up of platform deck, floating body and mooring, which is a kind of floating offshore engineering structure. This equipment occupies multiple functions, such as fishing, sorting, refining, storage and so on. Winch motors (ground net machine and anchor winch), cargo winch, generator unit, scallop separator, working cabin, accommodation and diesel generator were installed on the platform, and solar power as the source of power. In addition, to keep the scallops fresh and achieve the purpose of saving space, 2 shellfish purification storage networks were also set below the platform. Compared with the trawl fishing, it would substantially reduce energy consumption, realize precision fishing, raise fishing efficiency, and decrease the cost of purification. In this paper, based on the comparative methods, the technologic and economic parameters and the economic assessment indices were selected for the establishment of the technical and economic evaluation model, which was to investigate the economy of offshore scallops capture working platform. Firstly, the platform trawling engine power, the platform span, the hauls of platform anchored one time, the lateral movement time of platform anchored one time, the trawling speed of platform and the total construction cost of platform were selected as the technologic and economic parameters. Secondly, the capture fuel consumption per unit area, the unit cost of fishing and the capture efficiency were selected as the economic assessment indices. Next, the technical and economic evaluation model was established according to the technologic and economic parameters and the economic assessment indices. At last, based on this model, the economic calculation of fishing methods including fishing vessels and scallops capture working platform was carried out by using the comparative method. The results showed that when the platform trawling engine power was 400-470 kW, the platform span was 0.5-3.0 km, the lateral movement time of platform anchored one time was less than 2 h, the trawling speed of platform was beyond 1.4 kn, the total construction cost of platform was less than 27.5 million yuan, the scallops capture working platform project had more advantages over the fishing method of fishing vessels. Meanwhile, from these data, it was concluded that the haul of platform anchored one time was not very sensitive to the effect of scallops capture working platform project. The offshore scallops capture working platform conformed the policy of energy saving and emission reduction that was in line with the national “Twelfth Five-Year Plan”. By further experimental verification, the analysis model and method can provide the economic theory reference for the fundamental changes in fisheries production mode in China. [ABSTRACT FROM AUTHOR]

Offshore platform is the base for ocean oil resources development, and it is an effective means to determine offshore platform' s injuries to inspect its low frequency vibration. A kind of wireless sensor and its acquisition systems for low frequency vibration inspection of offshore platform are presented. Firstly, the wireless low frequency vibration sensor is designed by modularization method, the choice of low frequency accelerometer and the design of power circuit are illustrated. Secondly, the embedded programs of the wireless low frequency vibration sensor and PC's acquisition software are introduced. Finally, inspection experiments using wireless low frequency vibration sensors on shake table are performed. The experimental results show that, the designed wireless low frequency vibration sensor has the characteristics of high resolution, easy installment, good low frequency performance and reliability, so it is very suitable for fast vibration inspection of offshore platform. [ABSTRACT FROM AUTHOR]

Super sonic separator is a new technology for natural gas dehydration and dehydrocarbon. Comparing to the traditional natural gas dehydration technology, it has advantages of low investments, high efficiency, low power consumption and small equipment dimension, but it has the disadvantage of high pressure drop. This paper discussed the application feasibility of the new technology on offshore platform dehydration and dehydrocarbon process, made a comparison with the traditional natural gas dehydration technology. [ABSTRACT FROM AUTHOR]

To deal with the difficulties in confirming the structure of neuron model and low forecast accuracy of grey theory, the grey situation decision theory based on new effect measure is proposed for the first time, and it is adopted to construct the structure topology of neural networks and determine the number of neurons in various layers and input-output computation of neurons. Then the grey neural network is taken as adaptive predictive inverse controller, which is implemented to the active control of jacket offshore platform. The simulation results show that the obtained grey neural network has strong robustness, and thus can be used to effectively control the displacement response on the top of jacket offshore platform under the random loads. [ABSTRACT FROM AUTHOR]

Ice load is the dominative load in the design of offshore platforms in the ice zone, and the extreme ice load is the key factor that affects the safety of the platforms. Firstly, the statistical properties of the global resistance and extreme responses of the JZ20-2 MSW, JZ20-2 NW jacket platforms in Bohai Bay are studied using random sampling analysis by Monte-Carlo method, considering the randomness of ice load, dead load, steel elastic modulus, yield strength and structural member dimensions. Then, based on the above conclusions, an efficient approximate method of the global reliability analysis for the offshore platforms is provided, which converts the implicit nonlinear performance function in the conventional reliability analysis to linear explicit one. Finally, numerical examples of offshore jacket platforms in Bohai Bay demonstrate the satisfactory efficiency, accuracy and applicability of the proposed method. [ABSTRACT FROM AUTHOR]

The effectiveness under optimal design of a Tuned Liquid Column Damper (TLCD) in suppressing wave-induced vibrations of offshore platform is studied in this paper. The problem is analyzed in the frequency domain with white noise excitation and wave spectrum excitation in this study. Optimum parameters of the TLCD for maximum reduction of peak structural responses to both models are calculated and compared. The numerical analysis results show that better control performance can be obtained when wave spectrum model is chosen. Directional wave spectrum which can describe the full nature of wind-induced wave is first addressed in the analysis so that the directional distribution can be considered. [ABSTRACT FROM AUTHOR]

Objective: To understand the status of occupational health surveillance for workers on offshore platforms. Methods: The research period was from 2014 to 2016. From 2014 to 2016, a cross-sectional survey method was adopted to select 429 people for offshore oil production, drilling and operation platforms and their first - line workers to conduct workplace occupational hygiene. Investigation, occupational hazard factor testing, occupational health check of workers, collation and statistical analysis of surveys and test data, and comparison of occupational health surveillance among workers of different types of offshore platforms. Results: From 2014 to 2016, the results of chemical harmful factors detection of occupational diseases in the offshore platform were in line with the national occupational health exposure limit requirements. The noise of some platform posts exceeded the standard, such as: oil platform oil, oil and oil and gas processing workers, diesel engines for drilling and working platforms. Worker noise exceeds national occupational health limits p[L(ex, 8 h)>85 dB(A)].There was a statistically significant difference in the occupational health of workers on the same platform with the age and length of service ( P <0.05). Conclusion: Workers on different platforms at sea may be subject to different levels of occupational health damage, and the occupational hazards brought by noise to platform workers are particularly prominent.