Authors:Eugene M. Khartukov Pages: 1 - 13 Abstract: The past, current status and future of the oil sector of Spain are considered and analyzed. The author uses methods of comparative and systematic analyses, which are implemented for assessing the Spanish oil in the context of the world, Europe and the EU. The article mainly concludes the Covid-19 pandemic has seriously hit the Spanish oil market, however, the pandemic has made inland oil demand and petroleum imports of Spain lower but the domestic crude oil production, which is currently close to zero, will unlikely increase in the near term. PubDate: 2022-05-26 DOI: 10.3968/12552 Issue No:Vol. 21, No. 1 (2022)
Authors:Ke LI, Gaofeng ZHANG Pages: 14 - 17 Abstract: Well-bore instability problems often occurred when drilling in the formations of Dongying Group and Shahejie Group in Block Chengbei of Shengli Offshore in the past, which led to various down-hole complex problems and seriously affected the comprehensive benefits. In view of this situation, a seawater compound-salt plugging drilling fluid system is developed. The system is obviously superior to the traditional polysulfonate system in rheology, inhibition, high temperature resistance, bentonite contamination resistance and lubricity, and the temperature resistance can reach more than 180°C. The application results of more than ten wells on several platforms in Shengli offshore show that the drilling fluid system has stable performance, convenient maintenance, strong clay inhibition, plugging and collapse prevention, the average well diameter swelling rate of all wells is less than 8.0%, and the cementing quality qualification rate is 100%. It can effectively control the formation mud making, and the waste drilling fluid is only 1/3~1/4 of the conventional water-based drilling fluid. After well completion, the plug can be removed by acidizing, which has achieved good formation damage controlling effect. PubDate: 2022-05-26 DOI: 10.3968/12555 Issue No:Vol. 21, No. 1 (2022)
Authors:Jiliang YU Pages: 18 - 26 Abstract: Pengzhou 5-4D well is a three-spud directional well deployed by Southwest Oil and Gas company in yadehe structure, Longmenshan Piedmont structural belt, West Sichuan depression, Sichuan Basin. The designed vertical depth is 7545m, the designed maximum well deviation is 89.59°, the actual completed drilling depth is 7150m, and the completed drilling deviation is 91.58°. The strata encountered by the well are Penglaizhen formation, Suining formation, Shaximiao formation, Qianfoya formation, Xujiahe formation, Xiaotangzi formation, Maantang formation and Leikoupo formation. Potassium polysulfonate drilling fluid is used for the first and second spuds of the well, and oil-based drilling fluid is used for the third spud. During the second spud in, Ma’antang formation collapsed and fell seriously, making tripping difficult. After sidetracking, by adjusting the treatment idea of drilling fluid, making rational use of pre hydrated bentonite slurry, using asphalt with different softening points and nano plugging materials, the problem of collapse and falling blocks was well solved, and the operations such as tripping, electrical logging and casing running were safe and smooth. The white oil-based drilling fluid system is used in the third spud in a pioneering manner, and the construction is smooth without downhole complexity, which provides valuable experience for the construction of marine formation drilling fluid in Pengzhou block in the next step. PubDate: 2022-05-26 DOI: 10.3968/12556 Issue No:Vol. 21, No. 1 (2022)
Authors:Licheng HE, Huaizhen ZHAO, Fei ZHOU, Xiuling LI Pages: 27 - 33 Abstract: The characters of deep wells in the central area of Junggar Basin include the burial depth of the reservoir is deep, the temperature of borehole bottom is high and the middle and the lower formations are developed with hard and brittle mudstones. The Toutunhe Formation and the Badaowan Formation are full of micro fissures which frequently caused sloughing, borehole wall collapse to happen. The average well diameter expansion rate exceeds 15% and logging instruments got blocked frequently. Based on the analyses of mineral composition and physical and chemical properties, Optimized drilling fluid formula was presented after evaluation of different size plugging agents and lubricants in order to heighten tight plugging performance. The result of Pressure Transmission experiment indicates that after optimization drilling fluid can prevent or stay the pressure transmission in mudstone effectively. The formula has been applied in Well Cheng 6 and the high-temperature and high-pressure filtration loss was only 8.0mL, the average well diameter expansion rate was less than 5%. The logging success rate reached 100%, exceeding the research target of 80%. Using this formula, the goals of stabilizing borehole wall and enhancing logging success rate have been achieved. PubDate: 2022-05-26 DOI: 10.3968/12557 Issue No:Vol. 21, No. 1 (2022)
Authors:Lu ZHANG Pages: 34 - 37 Abstract: In the drilling blocks of shengli oilfield, the application of compound salt drilling fluid is becoming a new normal. Utilize compound salt drilling fluid could make a contribution to reduce the enlargement rate of hole diameter, also resolve the sticky and reaming problems in the upper section of Guantao formation and the wellbore instability problem of Shahejie formation under the condition of wellbore is clean. This paper is going to introduce what is compound salt drilling fluid system and the advantages of this system, and analyze the application of this drilling fluid in Yong559 drilling block. According to the wellbore diameter data, it approves that the compound salt drilling fluid system has a significant effect on reducing the enlargement rate of hole diameter. PubDate: 2022-05-26 DOI: 10.3968/12558 Issue No:Vol. 21, No. 1 (2022)
Authors:Eugene M. Khartukov Pages: 38 - 50 Abstract: The past, current status and future of the oil sector of Italy are considered and analyzed. The author uses methods of comparative and systematic analyses, which are implemented for assessing the Italian oil in the context of the world, Europe, and the EU. The article mainly concludes that the COVID-19 pandemic has impacted the Italian oil market more seriously than any other European countries, but its prospects are still quite good. PubDate: 2022-05-26 DOI: 10.3968/12553 Issue No:Vol. 21, No. 1 (2022)
Authors:Guohai ZHAO Pages: 51 - 57 Abstract: In order to solve the problem of wellhead equipment damage caused by vibration, impact and eccentric wear of wellhead drill string in the process of offshore extended reach well drilling, the finite element method is used to simulate and calculate the load state and deformation of cantilever beam of drilling platform under different working conditions, and the deformation is converted into wellhead offset according to the geometric relationship of position, so as to analyze the influence of wellhead deviation on eccentric wear of drill string; Based on the mechanical analysis of the drill string, the lateral force and casing wear of the wellhead are quantitatively analyzed. Taking an extended reach well in Chenghai as an example, the problem of wellhead drill string collision is analyzed. The theoretical analysis method of wellhead collision is helpful to guide the drilling operation of offshore extended reach wells. PubDate: 2022-05-26 DOI: 10.3968/12559 Issue No:Vol. 21, No. 1 (2022)
Authors:Daniel Oji Ndem, Stanley I. Onwukwe, U. J. Obibuike, N. U. Okereke, N. C. Izuwa, C. M. Ohaegbulam Pages: 58 - 64 Abstract: Sand production has been the prime challenge daring the hydrocarbon industry due to its unacceptable influences on oil recovery factor, surface and subsurface production facilities especially in the Niger Delta where the landscape is festooned with unconsolidated sand face. The production of sand reduces the oil recovery volume resulting to deficit economic withdrawal due to shutdown periods for remedial works and replacement cost of damaged equipment. So much exertion has been made on forecasting the sand face breakdown and/or sand production rate, most of these prediction models typified high reliance on geo-mechanistic approach which is hinged on rock mechanism alone. This paper therefore homogenized the rock, reservoir and production data such as compressive strength pressure drawdown, water cut, and production rate, confining pressure, viscosity and sand grain size to develop a simplistic predictive model for sand production rate by applying Buckingham Theorem. The model through its development proved that the collapse of formation sand face does not necessarily translate to sand production but the onset of water-cut triggers sand production. The model was explicit on sand grain size affect on sand production, it nullified the argument expressed in some researches that sand grain size affects sand production; it also showed that viscosity of the fluid is not influential on sand production rate. The model was validated using a real reservoir data from one of the wells in the Niger Delta. PubDate: 2022-05-26 DOI: 10.3968/12560 Issue No:Vol. 21, No. 1 (2022)
Authors:Eugene M. Khartukov Pages: 65 - 72 Abstract: The past, current status and future of the oil and gas sector of Bahrain are considered and analyzed. The author uses methods of comparative and systematic analyses, which are implemented for assessing the Bahraini hydrocarbons in the context of the world, the Middle East, and the Persian Gulf area. The article mainly concludes that the Covid-19 pandemic has seriously hit the Bahraini oil market (harder than the other sectors of the national economy), however, the pandemic has made inland oil demand and petroleum imports of the kingdom lower but the domestic crude oil production will unlikely increase in the foreseeable future above 200 kb/d, despite the significant discovery of HCs announced by Bahrain’s officials in early 2018. PubDate: 2022-05-26 DOI: 10.3968/12604 Issue No:Vol. 21, No. 1 (2022)
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