PACKER Russian patent published in 2007 - IPC E21B33/128 

FIELD: oil production industry, particularly downhole equipment adapted for repeated pressure testing of pipe string intervals inside well.

SUBSTANCE: packer comprises mandrel with figured slot formed in outer surface thereof, wherein the slot includes alternating axial short and axial long parts. Packer also has support, as well as sealing member and cone arranged below the support. The cone is fixedly secured to the mandrel. Packer also has collar installed on the mandrel so that the collar may perform axial movement in axial direction. The collar is provided with spring centrators and guiding pin arranged in the slot. Slips spring-loaded inside the collar in radial direction is connected to the collar around perimeter thereof. The short and long parts of figured slot are connected with each other through figured part. Head is connected to packer mandrel through the cone. Shaft with radial orifices and central channel passes through the head so that the channel is over the head. The shaft is provided with annular extension from below. The annular extension may cooperate with the head, wherein the shaft may be inserted in the head in air-tight manner and sealed inside the head from below. Upper shaft part is connected with weight. Shaft also has annular recess formed in outer surface thereof near upper edges of radial orifices. Centrators are located on outer mandrel surface over radial channels. Centrators define a circle circumscribed around centrators and having diameter, which exceeds diameter of sealing member in transport position. Low shaft end is perforated and provided with through orifice. Low shaft end has plug used as weight. Sealing member is arranged on outer shaft surface and retained from below with head. Shaft is fixed from above with support, which may slide relatively the shaft within the confines of annular recess thereof.

EFFECT: possibility to perform pressure testing of small-diameter pipes during well operation and repair, reduced time and decreased costs of repair works, reduced costs of device manufacturing.

3 dwg