Patent ID: 9605502
Date: 2017-03-28
CPC Classifications: E21B

Claim:
1. A method of operating a system for handling an influx of gas into a marine riser during the drilling of a well bore, the method including the steps of: operating a first riser closure apparatus to close the riser at a first point above a flow spool provided in the riser, there being a riser gas handling line extending from the riser at the flow spool to a riser gas handling manifold; operating a second riser closure apparatus to close the riser at a second point below the flow spool so as to form a volume in the riser between the first riser closure apparatus and the second riser closure apparatus, and to shut-in the well bore so that a flow of fluid from the well bore below the second riser closure apparatus into the volume between the first riser closure apparatus and the second riser closure apparatus does not occur; pumping fluid into an inlet line that extends into the riser at a point above the second point but below the flow spool; and operating a choke provided in the riser gas handling manifold to maintain the pressure in the inlet line or the riser at a substantially constant pressure, wherein, the pumping of the fluid into the inlet line that extends into the riser at the point above the second point but below the flow spool, and the operating of the choke provided in the riser gas handling manifold to maintain the pressure in the inlet line or the riser at the substantially constant pressure are each performed when the first riser closure apparatus has closed the riser at the first point above the flow spool, and the second riser closure apparatus has closed the riser at the second point below the flow spool to shut-in the well bore so that a flow of fluid from the well bore below the second riser closure apparatus into the volume between the first riser closure apparatus and the second riser closure apparatus does not occur.