The invention belongs to the field of small-and-medium-
diameter deep hole processing, and particularly relates to a self-deviation-rectifying
system for small-and-medium-
diameter deep hole processingbased on the
hydraulic pressure. The self-deviation-rectifying
system comprises an inner rotation body, an outer rotation body and a driving mechanism; the inner rotation body is arranged on the periphery of a
drill rod in a sleeving mode and is fixed relative to the
drill rod; the position between the inner rotation body and the outer rotation body is filled with
cutting liquid, so that a flow channel is formed between the inner rotation body and the outer rotation body, the flow channel comprises a plurality of wedge-shaped flow channels which are evenly distributed in the circumferential direction, and when the driving mechanism drives the inner rotation body to rotate, the
cutting fluid enters the small ends from the large ends of the wedge-shaped flow channels; and a pressure flow anda
shear flow are superposed to generate
oil film pressure to realize self-centering and self-deviation-rectifying of the
drill rod. A wedge-shaped flowing space is formed between a wedge-shaped solidbody and an outer sleeve, and in a
normal state,
oil film pressure of the wedge-shaped space provides circumferentially-symmetrical self-centering force; and when the drill rod deflects, the wedge-shaped space generates the
oil film pressure, namely self-deviation-rectifying force, the drill rod can be 'pushed back' to the correct axis through the self-deviation-rectifying force, and self-correcting of axis deflection is achieved.