Dual Spacer™ E spacer is a low-viscosity, weighted flush for primary and secondary cementing operations that can be used at temperatures from 60°F to 500°F (16°C to 260°C). The spacer volume should provide a minimum of 4 minutes contact, with a preferred contact time of 8 to 10 minutes or 1,000 annular feet. If Dual Spacer E spacer is the only spacer or flush run, no less than 400 annular linear feet of spacer is recommended, regardless of contact time.
Dual Spacer E spacer can be designed to displace water- and oil-based muds. It can be formulated with fresh water, seawater, 3% KCl, and salt concentrations as high as saturation. Its rheological properties typically allow it to be pumped in turbulence at reasonable displacement rates. These properties help improve mud displacement while maintaining drilling fluid and cement-slurry isolation.