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CT-RHM is a liquid rheology modifier used in oil‐base mud systems. It increases low‐shear‐rate viscosities (LSRV) and gel strengths for improved hole-cleaning. The primary application is in large‐diameter, high‐angle, horizontal and extended‐reach wells to increase cuttings‐carrying capacity. This permits higher rates of penetration while maintaining wellbore stability. It produces the highly shear‐thinning rheological profile in oil mud systems, when used in proper concentrations. Normal concentrations range from 1 to 4 lb/bbl (2.85 to 11.4 kg/m3), depending on the brine content. It is activated by calcium, shear and temperature.



  • It is used to improve cuttings transport in large‐diameter or directional wells, especially wells with diameters greater than 8 ½“. or deviations greater than 25°.

  • It modifies the rheological profile of oil‐base muds, increasing their shear‐thinning and thixotropic characteristics without using additional clay‐base additives.

  • It can be used in the existing oil‐base mud systems, as well as in freshly prepared mud, to prepare a system with increased LSRV and gel strengths. Sufficient shear is required to develop this increase in rheology, especially in freshly prepared muds.


  • Improves the rheological profile and hole cleaning capacity of oil base mud

  • Produces a more shear‐thinning rheology profile as compared to alternative oil‐mud gelling agents

  • Increases LSRV and gel strengths with minimal yield point and plastic viscosity changes; gels tend to be fragile and non‐progressive

  • It can be used in existing systems or in freshly prepared mud

  • Less maintenance required in the system.



Appearance:        Amber Viscous Liquid

Specific Gravity:  0.90-0.91

Pour Point:           35°F

Flash Point:          175°F


CT-RHM is packed in 55 gal HDPE or Steel Drums.



CT-RHM is equivalent to VERSAMOD (M-I) and RHEMOD L (Baroid)

For TDS, MSDS or further enquiries, please write to

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