Blowout Preventers – Annular Blowout Preventer and Ram Blowout Preventer

Blowout preventers (BOPs) are used to control blowout. The crew usually install several blowout preventers (BOP stack) on top of the well, with an annular blowout preventer at the top and at least one pipe ram and one blind ram blowout preventer below. Also, some well control techniques require both the annular and the ram blowout preventers.

An annular blowout preventer has a rubber sealing element that, when activated, seals the annulus between the kelly, the drill pipe, or the drill collar. If no part of the drill stem is in the hole, the annular blowout preventer closes on the open hole.

Ram blowout preventers are large steel rams, that have sealing elements. One type of ram blowout preventer is called a pipe ram because it closes on the drill pipe; it cannot seal on open hole. Blind ram blowout preventers are straight-edged rams used to close an open hole.

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Drilltech Manufacturing Company is a professional company engaged in R&D, design manufacturing of blowout preventers (BOP), diverters, electromagnetism eddy current brakes and hydraulic disc brakes and Silicon control rectify system(SCR) for offshore and onshore drilling operations.We have provided our products and services applied in offshore platforms,land rigs well testing,well test mining,coal bed methane extraction,shale gas exploitation,to many countries Such As the United States, Norway, Canada, Russia, Iran, Dubai, India, Indonesia, Azerbaijan and others.The quantity of well control systems we supplied specializing in drilling platform has been ranked third in the world.Among our products,49 1/2” diverter for offshore drilling operation is the most remarkable which has been patented with 9 items,Moreover,Drilltech is the second supplier that owns this technology after the GE company in the world.

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