Patent ID: 7540838
Filing Date: 2009-06-02
Classification: B04B,E21B

Abstract:
1. A system for controlling viscosity of drilling fluid, the system comprising a container of drilling fluid material, the drilling fluid containing solids, a viscosity sensor for sensing viscosity of the drilling fluid material in the container and for producing viscosity signals indicative of said viscosity, a centrifuge for removing solids from the drilling fluid material, the centrifuge having a rotatable bowl and a rotatable screw conveyor, pump apparatus for pumping drilling fluid material from the container to the centrifuge, bowl drive apparatus for driving the rotatable bowl, conveyor drive apparatus for driving the rotatable conveyor, pump drive apparatus for driving the pump apparatus, and a control system for receiving viscosity signals from the viscosity sensor and for controlling the centrifuge and the pump apparatus in response to said viscosity signals so that selected solids from drilling fluid material processed by the centrifuge are removed to control viscosity of drilling fluid material in the container.