What is a packer?
Packer is a downhole tool with elastic sealing elements to seal the annular space between various sizes of tubing string and wellbore, and between tubing string, and to isolate production zones in order to control production (injection) fluid and protect casing. (I.E. A downhole tool that separates different reservoirs and water layers in a wellbore and withstands a certain pressure difference.)
In oil production engineering, packers are used for stratification, and oil production channels are designed on packers.
When seaing, the piston sleeve goes up and the oil production channel is opened. After sealing, the upper pressure acts on the balancing piston and pushes the rubber cylinder upward to prevent the release pin from shearing force. When unpacking, the sealing pin is sheared by the friction between the rubber cylinder and the casing. The piston sleeve goes down to close the oil production channel.
It reduces the water shutoff construction process of oil well packer. It also realizes the operation of not killing well and not releasing blowout conveniently, and can withstand high pressure bidirectionally and has long service life.
It is widely used in drilling, cementing, testing, completion and other operations. It is also used in downhole oil operations.
For example, the outer casing packer used in cementing process is used to seal the annulus between casing and wellbore to form a permanent bridge plug, so as to prevent formation oil, gas and water from channeling due to cement solidification weightlessness during cementing process.
In the process of drill pipe testing, the drill pipe packer separates the upper formation, drilling fluid from the test layer.