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Liaohe oilfield is the biggest production base of the heavy oil in China. There are more than 800 horizontal wells with thermal recovery in the heavy oil reservoirs. Most of them adopt screen to complete the wells without packer outside of the casing, which results in packing off annulus space between screen and layer and only commingled steam or step steam can be injected inside the screen. Because of the areal and vertical anisotropy of the reservoirs, the horizontal sections are exploited unequally. According to the statistics, the horizontal wells with nonuniform exploitation accounts for 80 percent of all the horizontal wells with thermal recovery, and only 1/3 to 1/2 of the horizontal sections are comparatively well produced. The oil well productivity is seriously affected. So based on step steam injection inside the screen, we have developed the segregated completion and segregated steam injection technology applied to the horizontal wells with thermal recovery in heavy oil reservoirs. By means of the research on the segregated completion technology and development of high temperature ECP and casing thermal centralizer, which formed the corresponding technology applied in the horizontal wells with thermal recovery. Till now this technology has been applied in 8 wells, and average cyclic steam/oil ratio increased 0.1 plus, and the uniform development level of the horizontal section has been improved and the oilfield’s development effect has been advanced obviously.

Influence of strain rate on mechanical properties of Fe-30Mn-3Si-4Al TWIP steel was studied by compression experiments, indicating that TWIP steel has strain rate softening effect, strain rate insensitivity, and also strain rate hardening effect. According to strain rate sensitivity m changing with strain rate, effect of strain rate on TWIP steel mechanical properties can be divided into three stages: quasi-static stage with strain rate ranging from 0.001 to 100 1/s; high-strain rate stage with strain rate ranging from 701 to 5108 1/s; super-high-strain rate stage with strain rate ranging from 10335 to 30147 1/s. Adiabatic temperature rise tends to increase with strain rate. Strain hardening exponent is divided into three parts: dislocation strengthening stage, twinning strengthening stage and thermal softening stage.