PRESSURE RELIEF NOZZLES

摘要

A pressure relief nozzle installs on the face of a drill bit, and provides a flow path for drilling fluid. The pressure relief nozzle has a larger internal flow area when flow rates through the drill bit are high, and a smaller flow area when flow rates are low. Upon reduction of the pressure relief nozzle's internal flow area, the pressure drop across the drill bit tends to stabilize due to the reduced flow area through the drill bit.