The invention discloses a
pressure control device for continuous circulating drilling. The
pressure control device for continuous circulating drilling comprises a body, a through hole for allowing a
drill rod to penetrate through is formed in the middle of the body, four rams are further installed in the through hole of the body, each ram is formed by splicing two half rams of the symmetrical structure, and each half ram is driven by a
hydraulic cylinder. The four rams comprise the blind ram, the slip ram, the bearing ram and the
pipe ram sequentially from top to bottom, wherein the blind ram, the bearing ram and the
pipe ram are arranged in parallel, and the slip ram and the bearing ram are crossed by 90 degrees. The
pressure control device can reduce pressure fluctuation of a
wellhead when single-joint unit or three-joint unit connection and disconnection circulation stops or starts, keep the pressure of the
wellhead stable, and can ensure that the formed well wall does not collapse to the greatest extent, drilling accidents are greatly reduced, and the risks of circulation loss, stratum
cracking, well kick, pressure differential sticking, and jamming of a
drill bit or bottom
drill combination are greatly reduced.