CTE Model 7000 Constant Speed Mixer

The CTE Model 7000 and 7100 Constant Speed Mixers provide all the necessary functions to mix cement slurries according to API and ISO specifications and recommended practices. These mixers can also be used to thoroughly mix other shear-sensitive dry or fluid materials. Detailed testing within the API has shown that the methods of mixing cement slurries will significantly effect the thickening time.

The Model 7000 and 7100 Mixers are designed in accordance to API Spec 10 and have constant speed operation independent of the line voltage and rate that cement is added to the mix water.Good practice indicates that the cement be added slowly over a fifteen second period as specified by the latest addition of API Spec 10.The Model 7000 and 7100 Mixers will hold speed constant during the fifteen second period without operator attention, so wide variations in shear rate are avoided. Variations in shear rate have been found to be a major source of differences in thickening time tests when other variables are held constant.

Tests within the API have also shown significant variations in thickening time as a result of worn or eroded mixer blades. Major differences in thickening time are eliminated by the use of hardened blades in the Model 7000 and 7100. The hardened blades resist erosion during the mixing process and retain their original shape and pattern many times longer than standard blades normally found on regular industrial mixers. Of course, worn, hardened blades will need to be replaced with new hardened blades after showing signs of erosion. The hardened blades offer two advantages when used with Constant Speed Mixer:

Increased reproducibility when measuring thickening time to reach 100 Bc units.
More efficient utilization of mixer blades.