No abstract

With the deepening of oilfield development, the amount of highly deviated (≥30°) layered water injection wells have increased year by year. In order to solve the technical bottlenecks such as poor sealing of the columns and short effective period of dispensing. The self-supporting step-by-step releasable packers with the outer diameter of 114mm and the highly deviated well ball seat are developed. The packer integrates the function of centering-righting, ball centering, spiral righting and stepping unblocking and the ball seat has self-locking function and able to meet the requirements of pipe string used in highly deviated wells within 60°. Through the field application, a highly deviated well-dispensing process technology suitable for the characteristics of Huabei Oilfield has been formed, it has a strong popularization and application value.

In order to solve the problems in the surface casing removal, the casing milling process is proposed to be used. Through the size and material selection of casing milling pipe, mechanical analysis of connection thread and the innovative design of casing milling shoes, a series of casing milling tools and the efficient casing milling process are formed. The field application results show that the milling process can smoothly mill to the predetermined position. After the milling process, the surface casings can be successfully removed by cutting and fishing. The efficient milling process studied in this paper can make the removal of the surface casing with low cast and high efficiency. Both social and economic benefits are remarkable and it has a broad application prospect.

A series of new anionic-nonionic surfactants, biophenol polyoxyethylene ether carboxylate (BPPC), were synthesized using biophenol as raw material. The chemical structure of anionic-nonionic surfactant was determined by Fourier transform infrared spectroscopy and elemental analysis. The effects of concentration and degree of polymerization on surface tension were investigated. These new surfactants have good surface activity. The critical micelle concentration (cmc) is 9.30 × 10−3 mol/L, 8.50 × 10−3 mol/L, 8.10 × 10−3 mol/L, and 7.71 × 10−3 mol/L. The corresponding surface tensions at CMC are 28.38. mN/m, 28.60 mN/m, 30.40 mN/m, and 30.00 mN/m. Then focus on the foaming properties of BPPC. The results showed that the concentration of surfactant and Ca2+/Mg2+ had certain effects on the foaming properties and foam stability of cashew nut-based surfactants. Due to the relatively good foam properties of BPPC, it has broad application prospects in detergents and petroleum recovery.