(vb.) Drilling. To prepare and pump cement into place in a wellbore. Cementing operations may be undertaken to seal the annulus after a casing string has been run, to seal a lost circulation zone, to set a plug in an existing well from which to push off with directional tools or to plug a well so that it may be abandoned. Before cementing operations commence, engineers determine the volume of cement (commonly with the help of a caliper log) to be placed in the wellbore and the physical properties of both the slurry and the set cement needed, including density and viscosity. A cementing crew uses special mixers and pumps to displace drilling fluids and place cement in the wellbore. See: bottomhole circulating temperature, bow-spring centralizer, casing point, cement head, centralizer, check valve, day rate, drilling fluid, float joint, free water, openhole, plug and abandon, reciprocate, scratcher, surface casing, turnkey, wait on cement. More Details: Defining Cementing: Well Cementing Fundamentals