DESCRIPTION

PBS Plug is a surface-mixed, pumpable plugging material, formulated to provide a rigid crosslinked gel structure. PBS Plug 500 and PBS Plug 2000 contain sized particles of borate-containing minerals and special polymers which provide formulating flexibility to meet various formation requirements in lost circulation applications. PBS Plug Activator a salt/magnesia compound, serves as a crosslink catalyst when mixed with PBS Plug.  Also, calcium chloride may be used as a secondary accelerator in cold-water applications, or to increase rigidity of the plug.  The polymers in the base product add viscosity and filtration control and are crosslinked by the borate anion in the sparingly water-soluble borate. The catalysts initiate the crosslink reaction by raising the pH and salinity of the fresh water mixture. This reaction is accelerated by the normally higher temperature in the wellbore.  PBS Plug Retarder and PBS Plug Activator-E are used to delay the set, increase the available pumping time, and broaden the window of possible applications.  PBS Plug Activator-E is especially useful for mixes where the base water is above 100° F. PBS Plug products are packaged in 25 kg sacks.

APPLICATIONS

PBS Plug is a unique system whose main application is the control of lost circulation.  The combination of PBS Plug and PBS Plug Activator satisfies the requirements for the majority of extreme lost circulation situations where anything from induced fractures to total losses are experienced.  The final consistency of the PBS Plug also allows it to be easily drilled after the chemical setting reaction has been completed.  Calcium chloride may also be added as a secondary accelerator to modify the PBS Plug shear strength for the following applications:

• Lost circulation pill
• Open hole cement retainer
• Pre-cement pad
• Profile modification
• Formation consolidating gel

The base density for 100 lb/bbl of PBS-Plug is 10.1 lb/gal but weights up to 17.0 lb/gal can be achieved with the addition of barite or other inert weighting material.

ADVANTAGES

PBS Plug offers the following advantages:

• Provides excellent fluid loss control
• Seals high permeability and fractured formations
• Does not shrink
• Exhibits high shear strength
• Bonds tightly to the formation
• Can be spotted through mud motors and bit nozzles
• Utilizes standard mixing equipment