Probe and method for obtaining rheological property value

A rheological probe unit for use in a cylindrical container rotatable about its axis and containing a substance having rheological properties, the rheological probe unit comprising:

• a base mountable in a wall of the cylindrical container;
• a resistance member extending from the base in a radial orientation when the base is mounted to the cylindrical container, and onto which a resistance pressure is imparted by the rheological substance when the resistance member is submerged and moved therein by rotation of the cylindrical container;
• a speed sensor adapted to provide speed values indicative of a speed at which the resistance member is moved in the substance at given points in time, in both a low speed range and a high speed range;
• a pressure sensor adapted to provide pressure values indicative of the resistance pressure at given points in time;
• a power source;
• a rheological value calculator powered by said power source and adapted to obtain a calculated value indicative of at least one of said rheological properties of the substance using both:
• a pressure value and speed value in a lower speed range corresponding to a given point in time;
• and
• a pressure value and speed value in a higher speed range corresponding to another given point in time, the rheological value calculator being configured to calculate a slope between the pressure value and speed value in the lower speed range and the pressure value and speed value in the higher speed range, the slope being indicative of a pseudo-viscosity rheological property being expressed in terms of units of pressure over units of speed;
• and
• an emitter;
• wherein the pressure values are measured by the resistance member.