Abstract: In a well drilling system a fire suppression apparatus includes a pressure rated bell nipple or enclosure member mounted on the blowout preventer and including an elongated central passage opening at one end to an enlarged bore portion adjacent a restabbing flange. Diametrically opposed convergent nozzles open into the enlarged bore portion and are connected to a source of pressure water and/or a source of pressure fire extinguishing fluid by way of a manifold and respective remotely controllable shut off valves and check valves. The enclosure replaces a conventional bell nipple and provides an added measure of fire suppression protection in the event of uncontrolled flow of well fluids from the well. Branch conduit sections are connected to the main conduit section of the enclosure to provide a cuttings evacuation fluid flow line and a fill up or well fluid diversion line.

Abstract: A well drilling system for drilling with gaseous drilling fluid, particularly natural gas, in a closed circulation path including an enclosure or bell nipple mounted on a wellhead between the wellbore and a rotary control head for the drillstem. The enclosure redirects the flow of cuttings laden gaseous drilling fluid being circulated out of the well and includes a plurality of fire extinguishing fluid injection nozzles arranged to inhibit or extinguish fire within the enclosure and the rotary control head. Drill cuttings are separated from the gaseous drilling fluid in a pressure vessel which includes separator baffles and a drill cuttings port and valve arrangement for dumping samples and substantial quantities of drill cuttings collected within the pressure vessel during operation of the system. The enclosure and fire extinguishing system may be used in conjunction with operations using conventional liquid drilling fluids and conventional liquid-solids separation equipment.

Abstract: A well drilling system for drilling with gaseous drilling fluid, particularly natural gas, in a closed circulation path including an enclosure or bell nipple mounted on a wellhead between the wellbore and a rotary control head for the drillstem. The enclosure redirects the flow of cuttings laden gaseous drilling fluid being circulated out of the well and includes a plurality of fire extinguishing fluid injection nozzles arranged to inhibit or extinguish fire within the enclosure and the rotary control head. Drill cuttings are separated from the gaseous drilling fluid in a pressure vessel which includes separator baffles and a drill cuttings port and valve arrangement for dumping samples and substantial quantities of drill cuttings collected within the pressure vessel during operation of the system. The enclosure and fire extinguishing system may be used in conjunction with operations using conventional liquid drilling fluids and conventional liquid-solids separation equipment.