Ball-Type Storm Valve System Improves Safety and Saves Rig Time

Abstract

ABSTRACT Safety and economy of offshore operations have been improved by application of a ball-type storm valve system (SVS) that can be installed without left hand rotation, thus eliminating the danger of unscrewing drill pipe joints. The new valve system is latched by setting an overshot down over a stinger and applying weight; releasing is accomplished by right hand rotation and lifting. A retrievable test, treat, and squeeze packer is installed below the valve. Design of the ball-type SVS offers these advantages : Ease of operation. When the system is set down, the ball valve automatically closes to shut the well in. Latching onto the system is accomplished without opening the ball. Since the ball valve is not opened by latching on for removal, it can be closed by setting back down in the event high pressure is detected below the SVS. Wireline equipment can be run through the SVS. High volumes of drilling fluid may be circulated through the SVS to condition the mud system prior to removing the SVS from the hole. Present paper discusses design of the valve, with operational schematics illustrating its operation. Field results are presented describing use of the SVS in stress situations and for some maintenance functions, and resumption of operations. Rig time savings are discussed.