Patent ID: 7237778

Claim:
A shut-off seal assembly for use with a vessel for holding a flowable material, the vessel employing a rotatable shaft with a longitudinal axis extending through an orifice in a wall of said vessel and having a vessel mechanical seal for assisting in preventing the escape of the flowable material along the shaft, said shut-off seal assembly comprising: a seal carrier comprising: a substantially cylindrical seal carrier body having a first side facing the vessel and a second side facing away from the vessel; at least one notch in said seal carrier body, said at least one notch having at least one engageable portion; at least one seal carrier hole extending through said seal carrier body; at least one connector corresponding to said at least one seal carrier hole and extending through a respective hole of said at least one seal carrier hole of said seal carrier body; and a seal on said second side of said seal carrier body; a sleeve disposed within said seal carrier, said sleeve comprising: a substantially cylindrical sleeve body having a cross-sectional interior diameter for securely receiving said shaft, said sleeve body having an outer surface; a first sleeve body end; a second sleeve body end; and a plurality of angled slots on said outer surface of said sleeve body, each of said slots corresponding to and able to receive said respective connectors extending through said seal carrier holes; a seal seat secured to said sleeve at said second sleeve body end of said sleeve for engaging with said seal when said assembly is in operation; a moveable rotation restriction device for restricting the rotation of the shaft engageable with said engageable portion of said seal carrier notch in response to the movement of said rotation restriction device; and a mounting flange for mounting said assembly to the vessel mechanical seal, said mounting flange having a first side facing said vessel and a second side facing away from the vessel, said mounting flange including a sealing ring on said side facing said vessel for engaging with said seal when said assembly is in operation, wherein said seal, said seal seat and said sealing ring are configured to form a flowable material-tight engagement when said assembly is in use.