The invention relates to the technical field of oil-gas field down-hole tools and provides a hydraulic type sleeve
pipe centralizer. The hydraulic type sleeve
pipe centralizer comprises a core shaft, a
hydraulic cylinder sleeve, a shearing
dowel, an expanding assisting block and a centralizer plate spring; the upper portion of the
hydraulic cylinder sleeve is mounted on the upper portion of the core shaft through a first fixing
assembly, a liquid inflow hole is formed in the side wall of the core shaft, and a
piston cylinder is mounted in a second annular cavity; a
piston rod is mounted at the lower end of the
piston cylinder; the lower end of the
piston rod is mounted on the outer wall of the core shaft through the shearing
dowel; the upper end of the centralizer plate spring is fixedly connected with the lower end of the
piston rod through a second fixing
assembly; the expanding assisting block is fixedly mounted on the outer wall of the middle of the core shaft; and the lower end of the centralizer plate spring is fixedly mounted on the outer wall of the lower portion of the core shaft through a third fixing
assembly. The hydraulic type sleeve
pipe centralizer is compact in structure, and stabbing and scraping over the well wall cannot be caused when the device is placed into a
drill hole; hydraulic expanding seal is adopted, the outer
diameter after expanding seal is large, the centering effect is better, center of a down-hole horizontal-section sleeve pipe is achieved, a
cement loop is uniform, and improvement of the well cementation quality is facilitated.