Abstract:

The severe situation of lost circulation in salt bed and casing damage in Zhongyuan oilfeld is increasing now. Through analysis of casing damage, this situation could be caused by the top-of-cement, perforating damage of the high-fragile sheath and poor deformability of cement stone. The problem of lost circulation in salt bed can be solved by using F27A anti-loss-circulation toughness reinforce agent for oil cement.The lab research and model perforating testing shown that F27A has the property of anti-lost, toughness reinforced, little filtration and zero free-water. The other engineering properties also satisfied the needs of cementing operations. In 5 different districts, the rate of cementing quality for 12 wells reached 66. 7%.Using multifunction slurries will be helpful to reduce the casing damage rate in highrigid sheath and salt bed region.

Key words: cementing, slurry, lost circulation control, toughness, salt bed