5.8 The Spacer

Generally, after the washing liquid and the cement slurry is mixed, they will pollute each other. In order to prevent the pollution, usually injected a certain amount of spacer after the washing liquid is injected, the spacer will not have reaction with the washing liquid and the slurry. The spacer with a certain mount of additives will have a bigger viscosity and also have suspension. It can replace efficiently the drilling mud and can prevent the slurry and drilling fluid mixing. Also it has good compatibility with the drilling fluid and additives.

The kelioil CS210S series spacer has good thickening effect is remarkable. And it has a high viscosity with a low density. It has good suspension for the weighting agent and insoluble solid or oil drop. It has high stability in saline or acid/ alkaline solution. It has a higher viscosity and can soluble in cold water.
Strictly, the spacer and washing liquid is not well cement admixture, but generally the spacer and washing liquid can make the slurry replacement efficiency increasing and inhancing the cementing quality, so t the two products are also called oil well cement additive.

Table 8-1 is the kelioil CS series spacer’s performance index.

Table 8-1 the spacer’s properties requirements