Introduction Blowout preventer stack equipment （介绍防喷器设备堆栈）.pdf

WELL CONTROL EQUIPMENT PROCEDURES WC-1 Introduction Preventing and, when prevention is not sufficient, respond- ing to potential uncontrolled releases of oil or gas (blow- out) is critical to safe drilling operations. A kick is an influx of formation fluids into the wellbore. A blowout is an uncon- trolled kick exiting the well at surface. Well control is a process that begins with spudding the well and is not complete until the well is put on production and all drilling operations cease. This chapter will examine equipment commonly used in well control and processes used to control kicks of oil or gas. Blowout preventer stack equipment Annular blowout preventer The annular blowout preventer is installed at the top of the BOP stack (Figure WC-1) and has the capability of closing (sealing off) on anything in the bore or completely shutting off (CSO) the open hole by applying closing pressure. The sealing device of an annular blowout preventer is re- ferred to as the “packing element”. It is basically a do- nut-shaped element made out of elastomeric material. To reinforce the elastomeric material, different shapes of me- tallic material are molded into the element. This keeps the elastomeric material from extruding when operating system pressure or wellbore pressure is applied to the bottom of the packing element. Since the packing element is exposed to different drilling environments (i.e., drilling fluid/mud, cor- rosive H2 S gas and/or temperature of the drilling fluid), it is Figure WC-1: Schematic (top) and photo of annular blowout important to make sure that the proper packing element is preventers. Photo courtesy GE Oil Gas. Top image, IADC