Cementing Services

Onshore Cementing Operations and Equipment

Purpose and Applications of Cementing
Cementing in onshore drilling operations serves multiple purposes, including sealing the wellbore to prevent water penetration, sealing the annulus after casing installation, addressing lost circulation zones, and plugging wells for abandonment or directional drilling

Cementing Process

Preparing The Cement
Before commencing cementing operations, it’s crucial to determine the required amount of cement and its physical properties, such as density and viscosity. This is achieved through caliper logs to measure the wellbore diameter and selecting the appropriate cement type and additives

Mixing Cement
Specialized mixers combine dry Portland cement with water to create the slurry. Additives such as accelerators, retarders, lightweight or heavyweight materials, and extenders are incorporated to tailor the cement properties to specific well conditions

Cementing The Well
After running casing into the well, an L-shaped cementing head is installed atop the wellhead to receive the cement slurry. Two wiper plugs, the bottom plug, and the top plug are used to prevent mixing and ensure proper placement of the cement slurry

Cement Placement
The bottom plug is introduced into the well, followed by pumping the cement slurry behind it. The float collar catches the bottom plug, allowing the slurry to enter the wellbore. Pressure is increased to rupture the bottom plug’s diaphragm, enabling the slurry to flow up the casing’s exterior

Once the desired volume of cement is pumped, a top plug is introduced to displace the remaining slurry and ensure proper placement. After the top plug reaches the bottom plug, the pumps are stopped, and the cement is allowed to set, forming a barrier between the casing and the wellbore

The time it takes for the cement to harden, known as thickening time or pumpability time, varies depending on well conditions. Specialized cements may be used for challenging environments, such as high temperatures or pressures, to ensure proper well integrity