Patent ID: 11933137
Assignee: ARMOR TOOLS INTERNATIONL INC.
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 16:
17. A pressure control apparatus, comprising:
a tubular body with an inner bore, a connection at an upper end and a connection at a lower end, the connections enabling the body to be connected in-line with a wellbore tubular;
a hollow piston slideably moveable within the inner bore of the body;
seals between the piston and the inner bore's inner surface;
a releasable holding structure for holding the piston in place until pressure on one side of the piston exceeds a threshold pressure, the piston being moveable when the releasable holding structure is released to slide within the inner bore;
a disc, being breakable and having a circular edge with a disc ledge and a domed surface, the disc ledge coupled to, spanning across and moveable with the piston, at least a portion of the disc being exposed to the inner bore, the disc dividing the inner bore into two volumes, each volume in fluid communication with one of the upper end and the lower end of the tubular body;
a disc breaking sleeve secured within the inner bore and positioned concentrically within the hollow piston, the disc breaking sleeve forming an annular chamber in which the hollow piston, when released by the releasable holding structure, can move axially relative to the disc breaking sleeve and the disc breaking sleeve including:
a cutting end, the cutting end being positioned such that when the releasable holding structure releases the piston for movement, the piston and the disc are free to move to strike the disc against the cutting edge and thereby break the disc to open fluid communication between the upper end and the lower end through the inner bore;
wherein the disc has a weakened portion in its body at a junction of the disc's circular edge with the disc ledge;
the disc has a circumferential groove with a circumference approximately equal to an inner diameter of the disc ledge disposed about where the domed surface meets an outer surface of the disc ledge; and
the disc ledge includes a ring sized to permit the disc breaking sleeve to strike the disc's body while preventing at least a portion of the broken disc from entering the wellbore tubular.