Abstract: A viscometer for measuring liquid viscosities based upon rotational deflections of a suspended bob. The viscometer comprises a deflection indicator, a deflection reader located at a spaced relative position with respect to the indicator, a rotating element which rotates in unison with the bob and includes either the deflection indicator or the deflection reader, and a magnetic bearing assembly which prevents any substantial change in the spaced, relative position of the deflection reader with respect to the deflection indicator.

Abstract: A reciprocating pump and a capillary viscometer utilizing the same. Preferably, the inventive reciprocating pump is a syringe pump comprising: a cylinder, an actuated piston, and a floating piston. A chamber is created between the actuated piston and floating piston which may be filled with a pressurant to establish the quiescent pressure of the test fluid. The capillary viscometer comprises: a capillary tube wound about a heated mandrel, a differential pressure transducer, and a reciprocating pump. Test fluid is first pumped at a known rate from a first chamber, through the capillary tube, and into a second chamber. The pump is then reversed and the test fluid is then pumped from the second chamber, back through the capillary tube, and back into the first chamber. The process may be repeated in a continuous, reciprocating manner.

Abstract: A method of estimating the compressive strength of a foam cement sample from a parametric measurement (base cement compressive strength) obtainable from conventional equipment, wherein standard laboratory measurements are used to establish the relationship between the base cement compressive strength, the volume percent entrained gas and the compressive strength of the subject foam cement.

Abstract: An acoustic method and system for determining the static gel strength of one or more cement slurry samples at wellbore temperatures and pressures. The cement slurry sample to be tested is maintained in a static condition inside an acoustic pressure vessel at a controlled temperature and pressure. A first transducer generates an acoustic signal which is transmitted through the sample. A second transducer measures and records the amplitude of the acoustic signal after it transits the sample. This data is then processed and the static gel strength of the sample is determined according to a predetermined relationship relating signal amplitude to static gel strength.