Micro Matrix® Cement Retarder (MMCR) is a liquid retarder designed for use in Micro Matrix cement.
MMCR can be used at bottomhole circulating temperatures (BHCTs) between 140°F and 250°F (60° and 121°C). Normal MMCR concentrations are 0.04 to 0.24 gal of retarder per 50-lb bag of Micro Matrix cement.
MMCR exhibits extreme retardation in conventional cements and should be used in Micro Matrix cement only. Operators should use caution when mixing Micro Matrix cement with conventional cement for the same job.
Micro Matrix cement retarder provides the following benefits:
Extended pumping times
Early cement-strength development
More predictable thickening times
Adaptability for offshore use
Improved slurry displacement rates at steady pressures
Casing and collar leaks are a common problem for injection operations in many wells. These leaks can be caused by corrosion, casing damage resulting from tool wear, or failure of the threads to provide an adequate seal. Squeezing the leaks with low-fluid-loss cement slurries can repair the leaks. However, if the casing collar leak is narrow or tight, standard API cements will not penetrate enough to provide a complete seal without requiring perforation. Tight leaks can restrict the entry of standard cement slurries as much as 500 psi in 10 to 20 minutes.