FIELD: mining engineering.
SUBSTANCE: cementing well unit contains a tubular element, a wiper plug, a window assembly and a bypass stop. The wiper plug includes the first end, the second end and at least one radial wiper. It corresponds to the cross-section of the inner space of the tubular element in shape. The wiper is adapted to push the cement grout, being in contact with it through the second end, through the tubular member due to the pressure applied to its first end by the fluid under pressure. The window assembly is located inside the tubular element and comprises of an opening radially extending through the window assembly. The radial wiper of the wiper plug corresponds in shape to the cross-section limited by the inner surface of the window assembly and the inner surface of the tubular element. The wiper plug is designed to push the cement grout through the window assembly. The bypass stop is positioned adjacent to the opening in the annular space between the outer surface of the window assembly and the inner surface of the tubular element. The bypass stop is configured to reduce the amount of fluid under pressure passing from the first end to the second end through the opening and the annular space.
EFFECT: improved system operation reliability.
20 cl, 10 dwg
