Definition:
Texas Iron Works (valve), it is the same as kelly cock! (see comment!)
Subject Area 1:
Drilling & Operations
Remarks:
It is a Kelly Valve which is also named Kelly Cock/Drill Pipe Safety Valve allowing free passage of drilling fluid. The valve can be used as a dill pipe safety valve or upper kelly valve to control blowout pressures, or as a lower Kelly Valve to prevent loss of drilling fluid when the kelly is disconnected. It has a pressure rating of 5,000psi or 10,000psi.