Frac plug device with an anchor mandrel assembly for a locked set configuration

A ramp type frac plug device of the present invention is a simplified, short and compact frac plug device to both maintain seal to the borehole wall and prevent premature release from the borehole. The frac plug device includes a cone, an anchor assembly, a cap member, a slip device, and a sealing member. In a set configuration, the frac plug device has both the friction fit engagement of the cone and the slip device and a single direction rachet locked engagement of an anchor ring with a threaded ring portion and an anchor mandrel with an exterior threaded mandrel portion of the anchor assembly. The ratchet lock engagement between the anchor ring and the anchor mandrel prevents backward movement of the cone away from the anchor mandrel so that the cap member engaged with the anchor mandrel locks the slip device in position on the cone.