Annular blowout preventer

According to the structure of the packing unit, the annular blowout preventers are divided into the tapering packing unit annular BOP and the spherical packing unit annular BOP.

The features of tapering packing unit annular BOP:

> The tapering packing units are exchangeable with the HYDRIL's.

> The added wear-belts to the original design can prevent and improve the cylinder-grinding because of unbalanced loading.

> The fortified rings can lift the whole BOP stack.

> Screws connection type is convenient for assembling/disassembling and exchange of the packing units.