For those not familiar with the oil & gas drilling process, the cement that is between the well bore and outside of the well casing is critical to the overall integrity of the well. PetroWiki defines its role:
Controlling the pressure is very important in the cement curing process to meet the specifications outlined in API and ISO standards. Improper curing can lead to well integrity issues, which may in turn affect safety, environmental, and production performance.
Cement is used to hold casing in place and to prevent fluid migration between subsurface formations.
This 1:51 YouTube video, Cement Analyzer Application: Be Confident that Your Cement Will Perform as Specified, describes the operation of the TESCOM ER5000 series electropneumatic controller.
It accurately controls the pressure when testing the cement at the same pressures it will experience when pumped downhole—regardless of temperature or density variations.