DEVICE FOR TREATMENT OF RESERVOIRS IN WELL Russian patent published in 2011 - IPC E21B33/12 

FIELD: oil and gas production.

SUBSTANCE: device consists of main packer with its hollow mandrel connected to radial channels arranged on different height exceeding thickness of reservoir. Also, the device consists of an additional packer. The main packer is made with an elastic collar installed between an upper support and a lower conic support; its is also made with a pass case rigidly attached to the lower part of the hollow mandrel by means of the upper support and having a shaped slot with short and long lengthwise sections on external surface below the lower support. A ring, making axial transfers, is arranged on the pass case. The ring has a pin positioned in the shaped slot, centralisers spring loaded outwards and oval sockets spring loaded inside. When the pin is in a working position, i.e. in a long lengthwise section of the shaped slot, the oval sockets interact with a conic section of the lower support by means of their internal chamfers. The additional packer is located above the main packer. The additional packer is made from an upper stop with a cylinder bushing, from a lower stop and an additional elastic ferrule positioned on the cylinder bushing between the stops. The additional packer telescopic and axially travels into the lower stop. The lower stop is rigidly attached to an upper part of the hollow mandrel, while the upper stop is equipped with an anchor and is connected to a string to be lowered into a well. Length of the hollow mandrel is chosen to overlap the largest reservoir in a well from both sides. A blind partition is installed in the pass case of the main packer or in the mandrel below the radial channels. In the disclosed device the blind partition is positioned on a lower end of the pass case of the main packer. The upper stop is composed from the anchor, and a support case with an internal cylinder groove. The support case interact with the additional elastic ferrule. The cylinder bushing is rigidly connected to the string and is inserted into the support case of the upper stop. Transfer of the bushing downwards is restricted with an external lug in the cylinder groove. The anchor is assembled of cone sectors with an internal recess; the sectors are connected with the support case and can travel radially. Also, the anchor has a hollow case pressed upwards by means of a spring and a washer. The case performs limited axial transfers downwards relative to the cylinder bushing with die heads spring loaded inside; the die heads radially travel relative to the hollow case of the anchor and inside they interact with the sectors of the cone pressed inside by means of a ring. A circular recess for the spring ring is made on external surface of the cylinder bushing. Above there are made an upper and lower circular lugs with conic faces. The upper circular lug interacts with the die heads, while the lower circular lug is located in internal recesses of the cone sectors. A circular taper is made on internal surface of the support case between the cylinder recess and the cone sectors; it is located below the circular recess of the cylinder bushing to facilitate interaction with the spring ring. The spring ring has an upper and lower faces The lower face ensures passage of the spring ring through the circular taper of the support case downwards only after elastic ferrules are set in a well. The upper face facilitates passage of the spring ring through the circular taper of the support case upwards with allowable force.

EFFECT: separate successive treatment of reservoirs regardless of reservoir height in multi-pay well and pumping reagents of any volume regardless of viscosity.

3 dwg