kelly valve description:
Kelly valves are also known as Kelly plug valves or drill pipe safety valves. A manual control valve in the drillstring cycle
System, it is one of the effective tools to prevent blowout. Kelly valve is divided into upper Kelly valve and
Lower the kelly valve. The upper kelly valve is connected between the rotary joint and the kelly. Lower kelly valve connected
Between the lower end of Kelly and the top of the drill pipe or between the lower end of Kelly. Full swivel spanner
Open the relief valve 90° to open and close. In the drilling operation, in order to avoid the occurrence of malignant accidents,
The kelly valve should be connected to both ends of the kelly to prevent fluid loss and blowout.