KLA-CURE Hydration Suppressant | SLB


Hydration suppressant

Schlumberger Oilfield Services

KLA-CURE hydration suppressant is a water-soluble, environmentally acceptable, organic compound that reduces the dispersion and swelling of reactive clay formations. It effectively inhibits shale or gumbo clays from hydrating and minimizes the potential for bit balling.

Typical Physical Properties
Physical appearance Amber liquid
Specific gravity 1.22 at 60 degF [15.55 degC]
pH (1% solution) 6.5–7.5
Solubility in water 100%
Flash point >200 degF [93 degC] (Pensky–Marten closed cup)
Pour point 0 degF [–17.8 degC]
Concentration, lbm/bbl [kg/m3] 4 [11.4]; 6 [17.1]; 8 [22.8]
Equivalents, galUS/bbl [L/m3] 0.392 [9.3]; 0.588 [14.0]; 0.780 [18.6]


  • No special mixing required; add directly to any freshwater, seawater, or saltwater system.
  • Pretreat the system with KLA-CURE suppressant before drilling reactive formations.
  • If M-I GEL viscosifier is used, prehydrate the viscosifier before adding it to a system treated with KLA-CURE suppressant.
  • Most effective in systems with minimal bentonite and low methylene blue test (MBT) values. MBT values in KLA-CURE systems remain relatively low. Large increases in MBT values may indicate undertreatment of KLA-CURE suppressant.
  • Most effective in fluids with 8–9 pH.


  • Effective shale hydration suppressant in all water-based mud systems
  • Lower toxicity and environmental acceptability at recommended concentrations
  • Mixes easily without special shearing equipment
  • Reduces the potential for bit balling when drilling gumbo shales
  • Temperature stable in excess of 300 degF [149 degC]
  • Low MBT values, reducing dilution and chemical treatment costs


  • The KLA-CURE suppressant limits clay hydration. All M-I GEL viscosifier additions for viscosity and fluid loss should be prehydrated in freshwater.
  • In nondispersed and high-solids systems, KLA-CURE suppressants may initially cause flocculation. Dilution or treatments with thinners may be necessary to control excess viscosity.
  • As a by-product of the manufacturing process, KLA-CURE suppressant contains KCl salt crystals. The addition of 1-lbm/bbl [2.85-kg/m3] KLA-CURE suppressant provides 230-mg/L potassium and 205-mg/L chlorides.
  • Not as effective in high pH fluids with values greater than 10.5.

Toxicity and handling

Bioassay information is available upon request. Handle as an industrial chemical, wearing protective equipment and observing the precautions as described in the safety data sheet.

Packaging and storage

KLA-CURE suppressant is packaged in 55-galUS [208.2-L] drums.