What is cement retainer used for?

What is cement retainer used for?

An isolation tool set in the casing or liner that enables treatments to be applied to a lower interval while providing isolation from the annulus above. Cement retainers are typically used in cement squeeze or similar remedial treatments.

What is cement plug in oil well?

Plug cementing is another remedial cementing technique and refers to the method of placing the cement slurry into the wellbore to create a solid wellbore seal or “plug”.

What is squeeze cementing?

Squeeze cementing is a dehydration process. A cement slurry is prepared and pumped down a wellbore to the problem area or squeeze target. The area is isolated, and pressure is applied from the surface to effectively force the slurry into all voids.

Do you get permanent retainers removed?

Permanent retainers aren’t truly permanent. They’re only called “permanent” because they can’t be removed easily, unlike removable retainers. Permanent retainers do eventually wear out, but they’ve been known to last for upwards of 20 years. When they wear out, they can be removed and replaced.

Are wire retainers permanent?

Permanent retainers consist of a solid or braided wire that is curved to fit the shape of your newly straightened teeth. The wire is cemented (bonded) to the inside of your front teeth to keep them from moving. Most often used on lower teeth, they are also called fixed, lingual wire, or bonded retainers.

How do you pump a balanced cement plug?

Pumping steps for balanced cement plug are as follows:

1. Pump 50 bbl of spacer.
2. Pump 37.9 bbl of cement.
3. Pump 23.1 bbl of spacer.
4. Pump 69.b bbl of drilling mud. ** You may under displace 2-3 bbl to create cement falling effect in drill pipe. **
5. Pull slowly above TOC.
6. Circulate bottom up.
7. Pull out of hole to surface.

What is well plugging?

A well is plugged by setting mechanical or cement plugs in the wellbore at specific intervals to prevent fluid flow. The plugging process usually requires a workover rig and cement pumped into the wellbore. The plugging process can take two days to a week, depending on the number of plugs to be set in the well.

What is plugging in oil and gas?

An oil or gas well is plugged and abandoned when it reaches the end of its useful life or becomes a dry hole. These operations include activities and tasks that present hazards to workers.

What is this ezsv plug for?

The plug was intended to form the base for a whipstock. About 20m below we had a cement plug (whipstock Co was not happy to set the anchor on the cement in this particular instance). Anyway, the EZSV appeared to set correctly (and was apparently wireline tagged) but was not tagged when RIH with whipstock.

Does the ezsv set correctly with Whipstock?

Anyway, the EZSV appeared to set correctly (and was apparently wireline tagged) but was not tagged when RIH with whipstock. Only theory so far is that plug setting mechanism was affected by the fact that we had a solid barrier close beneath with incompressible fluid between the plug and the cement.

What is a balanced cement plug used for?

A balanced cement plug is sometimes placed to simply “backfill” a severely washed out or elliptical hole section.

How do cement plugs seal off dry holes?

To seal off selected intervals of a dry hole or a depleted well, operators can place a cement plug at the required depth to help prevent zonal communication and migration of any fluids that might infiltrate underground freshwater sources.