Applications for Liquid Casing® Fine & Liquid Casing® Coarse

1. Defining the Problem
   
   Losses occur through porosity fractures, vugs and unconsolidated formations. It is important to correctly define the type of loss and apply the correct application. The following procedures have been shown to be effective, but they are for general guidance, and advice from Liquid Casing Inc. should be sought for a particular application.
   
   
   
2. Drilling Unconsolidated Surface Sands
   
   Although losses occur, they are generally accepted in this phase of drilling. However, in order to prevent differential sticking and, thick build up of wall cake, pills containing 20-25 lbs/bbl Liquid Casing® Fine should be spotted on connections to improve the integrity of the formation being drilled.
   
   Mix: 20-25 lbs/bbl Liquid Casing® Fine into the pill pit using the mud being used to drill the section with as the base fluid. Spot the pill on connections. Determine the size of the pill from the volume of new hole.
   
   
   
3. Cementing
   
   Where known mud and cement losses occur while cementing, preparation of a Liquid Casing® Fine  Liquid Casing® Coarse pill to pump ahead of the cement spacer is advisable.
   
   Mix: 15 lbs/bbl Liquid Casing® Fine and 15 lbs/bbl Liquid Casing® Coarse into a pill pit using drilling mud from the circulating system. The size of the pill depends on the casing size and the following volumes of pill to be run ahead of the cement are recommended.
   
   

   Size of casing/liner	Volume of Pill in Barrels
   20'	250
   13-3/8"	150
   9-5/8"	100
   7"	50

   
   
   
4. Porous Under Pressured Formations
   
   Liquid Casing® Fine has been successfully used in porous under pressured formations, as well as over-pressured formations.
   
   The concentrations of Liquid Casing® Fine recommended allows for wastage over the shakers. It is also recommended that 25 lbs of Liquid Casing® Fine be added to the circulating system for every 100 ft drilled to maintain concentration levels. An example of this kind of application is discussed in the SPE/IADC Paper No. 21913 .
   
   
   
5. Drilling into Depleted Sandstone Reservoirs
   
   This is fully described in Section 9 in SPE/IADC Paper No. 21913.
   
   
   
6. Reservoir Clean Up After Working Well Over
   
   Well clean up after the use of Liquid Casing® Fine in kill pills, has proven to be substantially shorter and without requiring acidizing, or similar stimulation, in comparison to standard methods used. Refer to Section 6 on RETURN PERMEABILITY STUDY .
   
   
   
7. Logging
   
   Liquid Casing® Fine and Liquid Casing® Coarse contain no chemical elements which would affect any type of logs. Past experiences have shown that log definition has been improved by the fact that Liquid Casing® Fine  drastically reduces the amount of filtrate and fines lost to the producing formations.
   
   
   
8. Uses with Slim-Hole Equipment, Mud Motors and MWD Equipment, Coil Tubing
   
   Liquid Casing® Fine has a small enough particle size to pass through the smaller apertures in core barrels, mud motors and MWD equipment.
   
   
9. Method of Sealing
   
   Liquid Casing® Fine and Liquid Casing® Coarse are unique amongst loss circulation materials as they are fine enough to enter the pore space and form a seal, but the plate like shape prevents deeper penetration. Normal LCM creates a mat on the surface.
   
   By entering the pore spaces, no wall cake build-up occurs, therefore eliminating the probability of the drill string scrapping the cake off the wall and allowing losses to continue.
   
   Liquid Casing® Fine is a one way sealant and only requires 5-10 psi back pressure to flush it out of the reservoir sands.
   

NOTE: Liquid Casing® Fine and Liquid Casing® Coarse should not be mixed with conventional LCM as a mud pill has proven to impair the sealing qualities of these products.