What are Lead and Tail Cement?

In some cementing operation, operators will pump 2 cement slurries, normally called “Lead Cement” and “Tail Cement”.  Both lead and tail cement have pro and con as described below.

Lead cement: Lead cement is in the top section of cement, where has lower both pressure and temperature (see figure above). It has lower density and strength than Tail cement; however, it is also cheaper than Tail cement.

Tail cement: Tail is pumped after lead cement because it must be settled at the lower section of well bore, where needs high strength cement (see figure above) . It has higher strength than lead cement, but it is more expensive than lead cement.

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