VERSAWET Oil-Based Mud Surfactant | SLB


Oil-based mud surfactant

Schlumberger Oilfield Services

VERSAWET oil-based mud surfactant is used primarily in relaxed-fluid-loss, lower-lime VERSA oil-based mud systems that use VERSACOAT oil-based mud emulsifier and surfactant. VERSAWET surfactant is an excellent wetting agent that is especially effective in systems using difficult-to-wet FER-OX hematite weighting agent. It is also effective at oil-wetting barite and drill solids and at reducing the adverse effects of water contamination.

Typical Physical Properties 
Typical Physical Properties Physical appearance   Dark brown/green, viscous liquid
Typical Physical Properties Specific gravity   0.95-1.05
Typical Physical Properties Flash point   >200 degF [93.3 degC] (Pensky–Martens closed-cup test)
Typical Physical Properties Pour point   44 degF [6.7 degC]


VERSAWET surfactant oil-wets weight material and drill solids to prevent water-wet solids, improves thermal stability, rheological stability, filtration control and emulsion stability while it improves the fluid’s resistance to contamination.

Concentrations for initial formulations range from 1 to 4 lbm/bbl [2.85 to 11.4 kg/m3] with daily treatments of ~0.063 lbm/bbl [0.18 kg/ m3]. The recommended treatment levels depend on the oil-water ratio, anticipated temperatures, desired properties and the other products used in the formulation.

The VERSA family of systems includes


  • Concentrated, powerful oil-wetting agent, used in low-lime/low-alkalinity fluids; prevents water-wet solids
  • Can reduce initial mixing costs and maintenance costs by reducing the amounts of other surfactants needed
  • Excellent wetting agent for difficult-to-wet weighting agents
  • Improves emulsion stability and helps prevent water in HPHT filtrate
  • Effective at counteracting the adverse effects of water contamination such as high viscosity, low emulsion stability and water-wet solids
  • Improves thermal stability, rheological stability, filtration control, and contamination resistance of oil-based muds


  • Not recommended for high-lime systems or in wells with temperatures lower than 200 degF [93.3 degC]. Under certain conditions in high-lime fluids, VERSAWET surfactant can cause undesirable viscosity increases. VERSACOAT additive is the recommended wetting agent for most high-lime, medium-temperature applications.
  • Environmental restrictions concerning the use of oils and oil-base fluids should be considered because VERSAWET surfactant is used in conjunction with oil.

Toxicity and handling

Bioassay information is available upon request. Handle as an industrial chemical, wearing protective equipment and observing the precautions described in the Material Safety Data Sheet (MSDS).

Packaging and storage

VERSAWET surfactant 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.