KLA-STOP Liquid Polyamine Shale Additive | SLB


Liquid polyamine shale additive

KLA-STOP additives.

KLA-STOP™ liquid polyamine shale additive is used in polymer-based drilling and drill-in fluids.

Shale inhibition is achieved by preventing water uptake by clays and by providing superior cuttings integrity. The KLA-STOP additive effectively inhibits shale or gumbo clays from hydrating and minimizes the potential for bit balling. The KLA-STOP additive can be added directly to the mud system with no effect on viscosity or filtration properties.

KLA-STOP additive is a liquid additive that acts as a clay hydration suppressant by intercalating and reducing the space between clay platelets so that water molecules will not penetrate and cause shale swelling. The KLA-STOP additive provides outstanding shale inhibition and minimizes dilution rates.

KLA-STOP additive chemistry additionally provides a buffered pH in the 9.0–10.0 range, possibly eliminating any required additions of caustic soda or potassium hydroxide. The recommended concentration is 1%–4% by volume, depending on shale reactivity and the amount of shale in the interval to be drilled. KLA-STOP additive concentrations should be monitored using a filtrate amine titration method. Premix dilution rates should be based on the depletion rates and the polyamine inhibitor concentration in the premix.

For reservoir drill-in fluid applications such as in the FLOPRO NT™ water-based reservoir drill-in fluid system, KLA-STOP additive compatibility with the reservoir should be evaluated through formation damage testing and filtrate and formation fluid compatibility testing.

It is important to monitor the cuttings condition at the shakers during drilling operations. Cuttings should be firm and dry inside. Sticky and balled-up cuttings may indicate insufficient inhibition from a low KLA-STOP additive concentration. The initial mixture may contain more KLA-STOP additive than specified in the mud program to act as a buffer against high consumption (e.g., 4–5 vol %).

KLA-STOP additive can also be used as a shale inhibitor in gravel-pack fluids to maintain wellbore stability during high-rate water packs.


  • Provides excellent shale inhibition and limits cuttings dispersion
  • Reduces accretion potential and consequently bit and BHA balling
  • In proper concentration, possibly eliminates the need for additions of caustic soda or potassium hydroxide by providing a buffered pH in the 9.0–10.0 range
  • Tolerates common contaminants such as cement, hard water, CO2, drill solids, and crude oil
  • Performs as environmentally acceptable for both offshore and onshore applications
  • Can be added to the active system without adverse effects on viscosity and filtration properties
Typical Physical Properties
Physical appearance Clear liquid
Specific gravity 1.0–1.075
pH (5% solution) 9.2–10.2

All specifications are subject to change without notice.


  • May have reservoir formation or formation fluid incompatibilities—test for incompatibilities
  • May precipitate some salts out of brine solutions—test for precipitation
  • Cannot be used with aldehyde-base biocide

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 (SDS).

Packaging and storage

KLA-STOP additive is packaged in 55-galUS (208-L) drums.

Store in a dry, well-ventilated area. Keep container closed. Keep away from heat, sparks, and flames. Store away from incompatibles.

FLOPRO NT and KLA-STOP are marks of M-I L.L.C., an SLB company.