Annular BOP (Imperial) FH28-70/105

1) Scope of Capability

The working pressure of this annular BOP is 70Mpa. It must be fitted with corresponding hydraulic control system. To be used independently, and can be used with FZ18-35 ram blowout preventer together, as well. To seal annuli of different sizes with one sealing element when drill tools, tubings or casings are in the hole.

To fully seal the wellhead when drilling tools are not in the hole. To seal the annular between the kelly, coring tools, wireline, slickline etc and the borehole when well blowout occurs during the operations such as drilling, coring and logging. To snub drill tools by 18°unscrewed butt welding tool joint with depressuring valve.

2) Main Structure and Principle

FH28-105 annular BOP mainly consists of shell, top cap, sealing element and piston. When the well is needed to be shut due to well kick, high-pressure oil pumped from control system passes from the lower oil port into the piston lower close chamber to move the piston upward and force the sealing element moving upward along the ball surface, and support braces will move closer to each other, thus the rubber between them will extrude toward the middle of the wellhead to seal the drill tools or completely seal the wellhead.

When opening the well, the piston is forced to move downward with hydraulic pressure, and the sealing element can reset by elastic force to open the well.