Then, mud of higher density is injected through the drill pipe and annulus fluid is choked out to remove the gas and the lighter mud while maintaining the pressure.

• 然后,通过钻杆注入浓度更高的泥浆,将环形间隙中的流体闭死,从而在维持压力的同时清除了天然气和较轻的泥浆。