Plugs are used during cementing operations to help remove dispersed mud (drilling fluid) and mud sheath from the casing inner diameter and minimize the contamination of cement. A bottom plug is pumped ahead of the cement slurry and behind the spacer. It wipes any remaining dispersed mud from the inner diameter of the casing as it moves down the string. When the bottom plug seats at the float collar, differential pressure ruptures a diaphragm on the plug, allowing cement to flow through, turn the corner at the bottom of the hole or toe end of a horizontal well and fill the annular space between the casing and the formation. Once the full volume of cement has been pumped, a top plug is dropped and pumped behind the slurry. The top plug wipes cement from the inner diameter of the casing and then seats at the float collar, resting on the bottom plug and causing a pressure increase at the surface indicating that the cement has been displaced. Top and bottom plugs are always different colors. Bottom plugs from Halliburton are red and top plugs are black.
High Wiping Efficiency (HWE®) Plugs
Top and bottom cementing plugs designed for high wiping efficiency to remove mudcake, mud film, rust and mill scale during cementing operations.
Non-Rotating (NR™) Cementing Plugs
Innovative design enhances drill-out efficiency. Requires only a tenth of the time (using PDC bits) to drill out the shoe joint.
SSR-II™ Subsurface Release II Cementing Plug System
Used to remotely release cementing plugs at a selected subsurface depth.
For more specifications:
http://www.halliburton.com/en-US/ps/cementing/casing-equipment/plugs/default.page?node-id=hfqela50
High Wiping Efficiency (HWE®) Plugs
Top and bottom cementing plugs designed for high wiping efficiency to remove mudcake, mud film, rust and mill scale during cementing operations.
Non-Rotating (NR™) Cementing Plugs
Innovative design enhances drill-out efficiency. Requires only a tenth of the time (using PDC bits) to drill out the shoe joint.
SSR-II™ Subsurface Release II Cementing Plug System
Used to remotely release cementing plugs at a selected subsurface depth.
For more specifications:
http://www.halliburton.com/en-US/ps/cementing/casing-equipment/plugs/default.page?node-id=hfqela50
