External casing packer for thermal recovery is a special tool for sealing oil, gas and water layers in downhole casing or open hole. Through the action of external force, it shortens the length of the rubber tube and increases its diameter, seals the annular space of oil and sleeve, and separates the oil (gas, water) layers above and below the packer, so as to realize the layered testing of oil and water wells, layered oil recovery, Layered water injection, layered reconstruction and plugging of water layers. According to the different working principles of the packer, the packer is divided into four types: self-sealing, compression, expansion and combination.

How External casing packer for thermal recovery works

Setting: The oil pipe is pressed, and the hydraulic pressure acts on the piston through the pressure guiding hole of the lower center pipe. After the setting pin is cut, the piston and the retaining sleeve of the circlip drive the circlip upward, compress the rubber cylinder, and seal the oil sleeve annulus.

Unsealing: Lift up the pipe string, drive the valve sleeve, outer center pipe, upper center pipe and key to go up along the keyway of the lower center pipe, the rubber cylinder is restored, and the packer is unsealed.

Well flushing: The incoming water is injected into the casing annulus from the casing, the hydraulic pressure acts on the well flushing valve, pushes the valve upward, compresses the spring, opens the well flushing channel for well flushing, and after the well flushing is completed, normal water injection. The well flushing valve is automatically closed under the action of normal water injection and oil injection and casing pressure difference.