A recently developed, portable cement laboratory instrument has been used to test cement consistency under actual downhole conditions. Control variables include pressure, temperature, and shear experienced by a cement slurry in the test. During a simulated temporary suspension of pumping, the device can perform static gel strength evaluations to help predict pumpability of the cement. In addition, the device can also perform static gel strength tests after the job to allow further cement quality evaluations.

When a computer is used with the instrument, the user simulates actual conditions of the lead, tail, or intermediate cement slurry. The computer uses this information to control pressure, temperature, and shear rate during simulation. Accurate simulation of job parameters can provide closer predictions of cement performance.

Portability of the instrument gives an additional option for the user as to where the instrument is used. In the laboratory, the cement testing instrument is used as an aid in slurry design to better meet job requirements. On location, such as on an offshore rig, the cement testing device can be used with well instrumentation and a microprocessor to acquire information about a cement job. The computer can calculate proper job parameters to be used to test the slurry. Slurry samples to be tested can be taken from the lead or tail cement. A closer prediction of the cement on-job performance is provided.

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