Advanced Materials Research Vols. 524-527

Abstract: In China, Three oil companies use all sorts of beam pumping units, but the operation of balancing adjustment is labor-intensive, low efficiency and adjustment accuracy in general. Many engineers try to improve these, so they design various kinds of devices to adjust the balance of pumping units, however, the intelligent level of most balance devices is low and the installation and maintenance is complicated and security is not high. In this design, pumping unit balancing adjustment technology for theoretical support, combined with mechanical and electrical system, an intelligent balancing adjustment device is designed. The experiment shows that after the installation of device, current degree of balance is optimized at 106%, besides energy saving reach to 8.5%.

Abstract: In view of the problem that fluid channeling between zones resulting from poor quality of cement sheath, a new casing centralizer is designed. The centralizer can make casing string in position as usual and seals micro-channels by the oil/water swellable rubber. Swellable rubber slices are inlaid in centralizer edges to add sealing efficiency. In order to seal diversion trenches effectively, axial moveable rubber bars are designed. During slurry injection, rubber bars are pushed upwards by differential pressure to open the flowpathes; after displacement, rubber bars reset under spring force. So, a circular sealing strip is formed by rubber slices and rubber bars for zonal isolation. In the paper, structure and working principle of this tool are described, materials and components are matched, structure strength is calculated, and the feasibility of the new tool is discussed.

Abstract: Introducing several new types of fracturing fluid which consist the low damage fracturing fluid (HPF), a new clean fracturing fluid (EFAS), alcohol radical fracturing fluid, summarizing several new technology such as floating prop pant fracturing technology, end sand strip controlling seam height fracturing technology, hydraulic injection layer fracturing technology and seam height controlled technology during fracturing, analyzing the corresponding fracturing Modification Techniques of different reservoir types. Developing the hydraulic fracturing technology for their oil fields based on the study at home and abroad is proposed.

Abstract: Due to the high temperature , great pressure and complex lithology of super-deep well bottom, there exist such problems such as high solid concentration, multiple but inaccurate treating chemicals, complex formulation with instability of drilling fluid system, resulting in a frequent occurrence of underground complex accident and a waste of a lot of manpower and material resources. Therefore, based on the analysis of performance factors of ultra-deep drilling fluid system, the approach of regulating water based drilling fluid properties of super-deep well has been found. Moreover, through screening and processing optimization of treating chemicals of ultra-deep well by single-factor method, three sets of anti-high-density and anti-high-temperature saturated brine drilling fluid systems with few kinds of treating chemicals, concise and simplified system, including: ① saturated brine drilling fluid with anti-temperature 180 °C and density 2.40 g/cm3 ; ② saturated brine drilling fluid with anti-temperature 200 °C and density 2.40g/cm3; ③ saturated brine drilling fluid with anti-temperature 220 °C and density 2.40g/cm3 . After the the evaluation of the overall performance of these three systems under respective experimental conditions, the results show that all of these systems have such advantages as good and strong rheology, water loss building capacity, inhibition, lubricity and blocking ability, etc, which could meet the requirements of ultra-deep drilling under different circumstances.

Abstract: To make binary low-tension system play a vital role in improving oil displacement efficiency and foam system expand swept volume, binary low-tension system alternates with binary foam system flooding laboratory research is carried out after the polymer flooding technology. The method of airflow is used to proceed with foaming performance experiments by nitrogen gas. Surfactant CYL which foaming performance is stronger has good compatibility with alkali-free surfactant. The evaluation of the interfacial tension experiments shows that surfactant HLX has a low interfacial tension; the HLX's ability of reducing interfacial tension is less affected by CYL. It is shown through experiment that displacement recovery of binary foam system is 7.84% and binary low-tension system is 5.87% after polymer flooding, as well as the injection pattern of (0.05PV binary foam system+0.05PV N₂+0.1PV binary low-tension system) alternating three times is best, which displacement recovery is 14.22% and 12.26% in natural core after polymer flooding. The injection pattern of profile control and oil displacement can attain a perfect effect after polymer flooding.

Abstract: In this paper, The tesile damage process of the blowout preventor shell material ZG25GrNiMo was researched using acoustic emission technique. Analyzed the acoustic emission characteristics in different damage phases of this material using parameter analysis and waveform analysis. The result indicated that the acoustic emission characteristics are different in yielding, plastic deformation and rupture process. The differences of frequency spectrums of different damage modes are evident.

Abstract: Simulation lateral well for ball sealer diversion was established in this paper. Experiments under different conditions were conducted in the laboratory. The results show that ball sealer diversion technique can really improve water injection profile. When the number of blocking balls in one layer is less than 10, flow rate change of layers is not obvious. When the number of blocking balls is more than 10, flow rate of the layer reduces quickly. When the formation variation coefficient is 0.62 and 0.79, the goal of ball sealer is very clear. Generally 42 to 48 balls are needed to achieve good diversion effect. Balls injected near the target layer can improve diversion effect, and increase of total flow rate can improve diversion effect. In the experiment, the overall utilization rate of the injected balls is from 30% to 50%, and accurate blocking rate is from 20% to 30%.

Abstract: According to the scaling status of the water injection wells in XianHe, scaling experiment using coupon is carried out with the pipe material N80 and J55, which are used in the water injection wells in XianHe. The results of the experiments show that the scales separated from the injection water are carbonate. Combined with the results of the experiments, comprehensive analysis of the effect the parameters on the scaling of the injection system are made, these parameters including the concentration of the scaling ion, temperature, pressure, flowing condition, surficial condition of the pipe, total suspend matter, pipe material and so on.

Abstract: The tubing, as a key ingredient in the well development, worked always under very complex stress and corrosion conditions, the failure of the tubing could cause huge losses. In this paper, a fractured 3-1/2″ P110SS tubing was analyzed through physical and chemical properties testing, SEM, EDS, and XRD method. The results showed that the failure of the tubing was belong to hydrogen sulfide stress corrosion cracking. The tubing material could not pass the SSC test, it was inappropriate to use in well contained high hydrogen sulfide.

Abstract: The fluid level of swabbing wells with packers or without packers is different from other wells’ when the swabbing wells are stopped swabbing, because the effect of gravity differentiation is obvious, which is used to calculate the sand face pressure. In the homogeny reservoir, flow mathematic model of build-up of fluid swabbing well in circular sealed stratum is built up under considering the well bore effect and skin factor. Then, the non-homogeneous equation’s exact solution in Laplace space of the model are acquired by using theory of Laplace transform and Bessel function ,then the chart of type curve and the matching of type curve are analyzed. Finally, the software of swabbing well’s fluid level build-up is developed which is used to calculate the formation parameters that are fitted the formation parameters calculated with other methods.