... . Style: Shaffer, Cameron, Hydril 2. Standard: API 16A ram bopAnnular BOP is an important part of well-control equipment. It mainly ... etc. to prevent well blowout effectively and realize safe construction.Annular BOP shall be equipped with hydraulic control system. It is usually ... during drilling, coring or well logging, it can seal the annular spaces between Kelly, coring tools, cable,wire line and ...