Cementing casing across highly depleted zones and weaker formations requires low-density cement systems capable of reducing the hydrostatic pressure of the fluid column during cement placement. Low-density or lightweight cement systems help achieve the specified top of cement by avoiding or minimizing lost circulation (losing cement to the formation). Halliburton offers cement solutions made light enough to circulate in such situations while retaining the ability to withstand downhole conditions.
Lightweight cement can be achieved in one of three ways: water extended, injection of gas (foamed cement), or by adding low-specific-gravity microspheres or other enhancing additives.
•Water extended: adding additional water to the cement slurry is a common means of reducing slurry density, yet it requires water-extending additives to help maintain slurry stability and overcome slow compressive strength development and low ultimate compressive strength.
•Foamed cement: Injecting gas (nitrogen, compressed air, or gas-generating solids) into the slurry provides the benefit of increased slurry compressibility, increase set-cement elasticity, and the flexibility to vary density during operations.
•Microspheres: While typically bulk blended, Halliburton also offers liquid-additive beaded systems, microspheres are available as ◦solid, plastic beads of approximately 1.0 specific gravity;
◦hollow-pozzlanic spheres of approximately 0.7 specific gravity;
◦hollow glass bubbles of approximately 0.32 to 0.61 specific gravity.
Properly designed microsphere slurries can achieve the highest strength-to-weight ratio and lowest permeability of any lightweight cement design. Additionally, microsphere slurries have a reduced transition time from liquid to cement setting, helping minimize the gas migration. Some other mechanical enhancement additives such as fibres may also assist with reduction of slurry densities.
Tuned® Light Cement
High-strength performance from a lightweight slurry
Tuned Light cements rely on microspheres to produce lightweight slurries with excellent strength characteristics. Tuned Light cement can yield strengths equal to or better than cements of equal density made by any other lightweight technique.
Advantages of Tuned Light cement can include:
•Low density. Tuned Light slurries offer a versatile range of potential densities, enabling operators to maximize returns and reduce the need for remedial top-up jobs.
•Thixotropic. Tuned Light slurries are thixotropic by nature, which is beneficial when cementing in areas of potential lost circulation and cement fall-back.
•Faster transition times. Tuned Light slurries can be designed for short transition times when required as gas-tight designs for wells with high gas flow potentials (GFP).
•Compressive Strength. Tuned Light slurries develop compressive strength at low densities and any temperature, and exceed the performance characteristics of conventional slurries under the same conditions.
For more specifications:
http://www.halliburton.com/en-US/ps/cementing/cementing-solutions/lightweight-cement/default.page?node-id=hfqela4a
Lightweight cement can be achieved in one of three ways: water extended, injection of gas (foamed cement), or by adding low-specific-gravity microspheres or other enhancing additives.
•Water extended: adding additional water to the cement slurry is a common means of reducing slurry density, yet it requires water-extending additives to help maintain slurry stability and overcome slow compressive strength development and low ultimate compressive strength.
•Foamed cement: Injecting gas (nitrogen, compressed air, or gas-generating solids) into the slurry provides the benefit of increased slurry compressibility, increase set-cement elasticity, and the flexibility to vary density during operations.
•Microspheres: While typically bulk blended, Halliburton also offers liquid-additive beaded systems, microspheres are available as ◦solid, plastic beads of approximately 1.0 specific gravity;
◦hollow-pozzlanic spheres of approximately 0.7 specific gravity;
◦hollow glass bubbles of approximately 0.32 to 0.61 specific gravity.
Properly designed microsphere slurries can achieve the highest strength-to-weight ratio and lowest permeability of any lightweight cement design. Additionally, microsphere slurries have a reduced transition time from liquid to cement setting, helping minimize the gas migration. Some other mechanical enhancement additives such as fibres may also assist with reduction of slurry densities.
Tuned® Light Cement
High-strength performance from a lightweight slurry
Tuned Light cements rely on microspheres to produce lightweight slurries with excellent strength characteristics. Tuned Light cement can yield strengths equal to or better than cements of equal density made by any other lightweight technique.
Advantages of Tuned Light cement can include:
•Low density. Tuned Light slurries offer a versatile range of potential densities, enabling operators to maximize returns and reduce the need for remedial top-up jobs.
•Thixotropic. Tuned Light slurries are thixotropic by nature, which is beneficial when cementing in areas of potential lost circulation and cement fall-back.
•Faster transition times. Tuned Light slurries can be designed for short transition times when required as gas-tight designs for wells with high gas flow potentials (GFP).
•Compressive Strength. Tuned Light slurries develop compressive strength at low densities and any temperature, and exceed the performance characteristics of conventional slurries under the same conditions.
For more specifications:
http://www.halliburton.com/en-US/ps/cementing/cementing-solutions/lightweight-cement/default.page?node-id=hfqela4a
