KLA-GARD shale stabilizer and inhibitor system | SLB


Shale stabilizer and inhibitor system

KLA-GARD system.

KLA-GARD™ shale stabilizer and inhibitor system reduces the swelling of sensitive shales and drill cuttings exposed to water-based drilling fluids. KLA-GARD system inhibits shale hydration, reducing the effect of drill solids on viscosity, and it works to minimize problems such as excessive dilution rates, increased torque and drag, high surge and swab pressures, and bottomhole assembly balling.

KLA-GARD system should be specified for applications where additional inhibition is needed as an alternative to gyp, lime, and potassium systems. This high-quality concentrated product has applications in a wide variety of mud systems and has such low toxicity characteristics it can be considered for offshore applications.

KLA-GARD system is compatible with most drilling fluid additives and is especially suited for use in freshly prepared low-solids polymer systems such as the POLY-PLUS™ high-molecular-weight liquid clay inhibitor. It is most effective when the use of organic thinners, such as SPERSENE™ chrome lignosulfonate, is minimized.

  • Reduces the amount of dilution required and the associated treatment costs
  • Reduces potential for bit balling
  • Highly effective shale stabilizer
  • Effective at all pH levels
  • Environmentally acceptable
  • Stable at temperatures in excess of 204 degC [400 degF]
  • Unaffected by contaminants such as hard water, cement, or CO2
Physical appearance Transparent to blue clear liquid
Specific gravity 1.05–1.15
pH neat 6.5–9.0
Solubility in water at 20 degC [68 degF] 100%
Flash point >99 degC [>210 degF] [PMCC]

All specifications are subject to change without notice.

Due to the powerful effect KLA-GARD system has on active solids, it should only be added to mud systems containing low concentrations of active solids, bentonite-free systems, or freshly prepared low-solids systems containing a minimum amount of prehydrated bentonite. These systems should have a methylene blue capacity of less than 35.6 kg/m3 [12.5 Ibm/bbl] with 5.7 to 14.3 kg/m3 [2 to 5 Ibm/bbl] of prehydrated bentonite for filtration control.

Normal concentrations of KLA-GARD system range from 11.4 to 22.8 kg/m3 [4 to 8 Ibm/bbl] depending on hole size, rate of penetration, interval length, and reactivity of the shale. A minimum concentration of 11.4 kg/m3 [4 Ibm/bbl] is required for the product to be effective. One Ibm/bbl of KLA-GARD system contributes 508 mg/L chlorides. To prevent bacterial attack, a biocide should be used.

KLA-GARD system works by being adsorbed onto active solids, thereby reducing their sensitivity to water. This action causes the product to be depleted from the mud system at a rate dependent on the reactivity of the formation, cuttings size, and amount of hole volume drilled. A test procedure is available to monitor the approximate concentration of excess KLA-GARD system.


  • Should not be added to systems containing high concentrations of active solids; flocculates muds with high methylene blue test (MBT) values, causing excessive viscosity.
  • Limits the hydration of all clay materials, therefore bentonite additions must be prehydrated in freshwater.
  • Due to the interaction of KLA-GARD system with active solids and bentonite, increased attention must be given to filtration control.
  • Product is biodegradable and requires a biocide.