If losses occur in reservoir sections, the following options are available:

As a first step, the mud gradient shall be reduced, formation pressures permitting.

If the gradient reduction provides no benefit, then use CaCo3 LCM material as follows:

Formulation and Mixing Procedure for LCM Pills

Calcium Carbonate shall be applied according to the details in the following table:

Loss Rate < 12 bbl/hr

Loss Rate 12 - 22 bbl/hr

Loss Rate 22 - 44 bbl/hr

Size

Conc.

Size

Conc.

Size

Conc.

50 micron

Add to circ system at

50 micron

15 ppb

50 micron

15 ppb

 

4 - 5 x 25 kg sx/hr

150 micron

15 ppb

150 micron

15 ppb

 

 

 

 

600 micron

15 ppb

Notes:

The material is totally soluble in HCl.

If all else fails then consider drilling blind to TD.