Pipe rheometer

A method of measuring a rheological graph of a fluid, the method comprising:

• retrieving a sample of fluid from a body of fluid;
• at least partially filling a reservoir with the sample of fluid;
• draining the sample of fluid from the reservoir through a measurement pipe;
• monitoring a level of fluid in the reservoir as the reservoir is drained, thereby determining a flow rate through the measurement pipe;
• identifying a pressure within the reservoir at a plurality of measurements as the reservoir is drained;
• calculating a shear stress for the sample of fluid from the identified pressure drop along rheometer pipe;
• calculating a non-Newtonian factor, n′ from the pressure drop and flow rate along the rheometer pipe;
• calculating a shear rate from n′ and the flow rate;
• and
• obtaining the rheogram of the fluid as a relation of shear stress versus shear rate.

A system for measuring rheological properties of a drilling mud for use with a drilling operation, the system comprising:

• a mud tank and mud circuit, wherein the mud tank holds the drilling mud and the mud circuit circulates the drilling mud from the mud tank to a drilling region and back to the mud tank;
• a mud diverter circuit fluidly coupled to the mud circuit and configured to retrieve a sample of the drilling mud from the mud circuit at a region proximate to the drilling region;
• a reservoir configured to receive the sample from the mud diverter circuit, the reservoir being further configured to determine a pressure within the mud in the reservoir and a level of fluid in the reservoir;
• a measurement pipe fluidly coupled to the reservoir and configured to drain the drilling mud from the reservoir;
• and
• a calculation component configured to plot shear stress against shear rate of the drilling mud of the sample from the pressure and the level.