Patent ID: 7526941

Claim:
A method of calibrating a rheometer comprising: obtaining a calibrating object with a certified moment of inertia calibrated by traceable means; recording the certified moment of inertia of the calibrating object; measuring a moment of inertia of the rheometer; recording the moment of inertia of the rheometer; fitting the calibrating object to one end of a drive shaft of the rheometer; measuring a total moment of inertia of the rheometer with the calibrating object fitted to the drive shaft; recording the total moment of inertia of the rheometer with the calibrating object fitted to the drive shaft; calculating a moment of inertia of the calibrating object by subtracting the moment of inertia of the rheometer from the total moment of inertia of the rheometer with the calibrating object fitted to the drive shaft; recording the moment of inertia of the calibrating object; calculating a torque adjustment factor by dividing the certified moment of inertia of the calibrating object by the moment of inertia of the calibrating object; recording the torque adjustment factor; applying the torque adjustment factor to subsequent rheological values measured using the rheometer.