UNI-VIS-byopolymer is used for drilling in non-cohesive soil (sand, gravel, etc.) for the purpose of increasing rheological characteristics (carrying capacity, gel strength). On high complexity job sites preferably to use it in combination with UNI-PAC;

UNI-VIS is a dispersible, non-clarified, high-molecular weight biopolymer used for increasing viscosity in water-base base drilling fluid systems.

Small quantities provide viscosity and weight material suspension for all water-base mud systems. Uni-Vos biopolymer has the unique ability to produce a fluid that is highly shear-thinning and thixotropic.

UNI-VIS HDD Polymer

Physical appearance Cream-to-tan powder

Specific gravity 1.5

Bulk density 50 lb/ft3 (800 kg/m3
The primary function of Uni-Vis biopolymer is to increase viscosity for cuttings transport and suspension. It performs effectively in all water-based fluids, ranging from highly weighted to low-solids systems. This includes freshwater, seawater, salt and heavy-brine fluid systems.

The amount of Uni-Vis required depends upon the desired viscosity. Normal concentrations range from 0.25 to 2 lb/bbl (0.71 to 5.7 kg/m3) for most mud systems. Special fluids and difficult hole-cleaning conditions can require higher concentrations of, up to 41b/bbl (11.4 kg/m3).

The addition of salt, antioxidant and thermal stabilizers improve temperature stability in fluids from 250 to >280° F (121 to >138° C). Specially formulated systems have been used at temperatures of 400° F (204° C). Uni-Vis is subject to bacterial degradation, and treatments with a biocide is recommended to prevent fermentation.
Highly effective viscosifier; with minimal treatments producing significant results

Shear-thinning rheological profile for improved hydraulics

Minimum frictional pressure losses for additional hydraulic horsepower at the bit and low, high shear-rate viscosity for maximum penetration rates

iscous laminar flow in the annulus for improved wellbore stability with maximum hole-cleaning and suspension capacity
Trivalent ions such as chromium and iron can cause biopolymer precipitation and loss of viscosity or crosslinking

Intolerant of high-pH or high-calcium-ion conditions

Uni-Vis systems should be pretreated with either sodium bicarbonate or SAPP and citric acid prior to drilling cement

Subject to bacterial degradation, a biocide should be used to prevent fermentation

The slightly anionic nature of Uni-Vis biopolymer requires special mixing procedures when combined with cationic materials

UNI-VIS HDD Polymer

Typical Physical Properties

Aplications

Advantagens

Limitations

Toxicity and Handling

Storage

Physical appearance	Cream-to-tan powder
Specific gravity	1.5
Bulk density	50 lb/ft3 (800 kg/m3