EA037854B1 - Multi-functional well clean-up complex - Google Patents

Abstract

The invention relates to oil and gas industry, to devices for well workover, in particular to devices for cleaning walls of a production casing from asphalt-resin-paraffin deposits (ARPD), filtering a well fluid from floating deposits and foreign matter, cleaning a well bottom from dense bridging, cleaning filtration channels of a bottom zone of a productive formation from colmatage deposits and mechanical impurities in one trip when performing regular well repairs and well workovers. A complex of multifunctional well clean-up is described, which includes a collar packer with a through channel between an upper outlet perforated nipple and a lower slotted filter, an internal connecting pipe that keeps tightness of the entire assembly having a throttle and a knock-out valve installed on its upper end, and a device for dense bridging removal installed on its lower end via an adjustable hydraulic bailer and a valve system. The technical result: obtained is a multifunctional, simple in design device to clean-up a well and a bottom zone of productive formation within one trip.

Description

The invention relates to the oil and gas industry, to devices for well workover, namely for cleaning the walls of the production casing from asphalt-resin-paraffin deposits (ARPD), filtering the well fluid from floating deposits and foreign matter, cleaning the bottom of the well from dense plugs, cleaning the filtration channels of the bottomhole zone of the productive formation from clogging deposits and mechanical impurities in one round-trip operation when carrying out current and capital repairs of wells.

Known RF patent for invention No. 2657651, which describes a collar packer with a central bore, which contains an upper adapter, upper and lower mandrels, fixed by expanding parts towards each other, self-sealing collars, centralizers, a lower adapter and a valve. The packer is equipped with an additional annular bore. The annular passage channel is connected with the outer space between the cuffs by means of radial holes. The central and annular passageways are formed by two concentrically installed pipes. The outer tube is mounted on top and bottom mandrels. The inner tube is installed in the upper and lower adapters. The adapters are provided with transverse channels connecting the central passageway of the inner pipe with the space above and below the collars, and vertical slots connecting the annular passageway with the internal cavity of the equipment installed above the packer, and the space under the collars below the packer.

A well-known patent has a narrow application specificity.

The task to be solved by the invention is to ensure the cleaning of filtration channels of the productive formation from clogging deposits, the bottom of the well from cuttings and mechanical impurities, the walls of the production string from asphalt-resin-paraffin deposits (ARPD) and well fluid from floating deposits and foreign substances in one round trip;

multiple use and long service life of the product;

the ability to conduct an audit in a well without the use of special devices and tools;

lack of high-wear consumables and parts.

The task is solved by using a complex of multifunctional well cleaning, including a collar packer with a through channel between the upper outlet perforated pipe and the lower slotted filter, an internal connecting pipe that maintains the tightness of the entire assembly, at the upper end of which there is a throttle and a churn valve, at the lower end through an adjustable a hydraulic thief and a valve system installed a device for eliminating dense plugs. The figure shows a view of the device.

The complex (see drawing) consists of the following main elements: 1 - whipped valve; 2 - throttle, in this case the throttle clutch; 3 - collar packer with an upper outlet perforated branch pipe and a lower slotted filter; 4 - inner connecting pipe; 5 - adjustable hydraulic bailer; valve system, consisting of 6 - ball check valve and 7 - poppet check valve; 8 - a device for the elimination of dense plugs.

The device operates as follows. The complex is lowered into the well together with the production tubing pipes. In the process of descent, from the first meters, the walls of the production casing of the well are cleaned from asphalt-resin-paraffin deposits using the edges of the plastic collar packer of device 3, while the well fluid is filtered from floating deposits and foreign matter, which passes through the lower slotted filter and exits through the upper outlet perforated pipe of the device in a cleaned form, while the integrity of the inner cavity of the container from the tubing pipes for the subsequent collection of sediments collected from the entire wellbore, floating debris, bottomhole and bottomhole cuttings is preserved due to the tight connection of the inner connecting pipe of the device 4 with the tubing string located above the device.

When the current bottom is reached, the device for eliminating dense plugs 8, intended for destruction by drilling out dense sandy and proppant plugs, deepens into the bottomhole sludge, and an adjustable hydraulic thief 5 is triggered, that is, the stem of the hydrostatic unit moves downward, opening the overflow holes, and the liquid together with mechanical impurities, bottomhole sludge and floating substances due to hydrostatic pressure rushes into the storage container and then, through an adjustable hydraulic thief 5, into the tubing. During the descent process, large floating debris accumulates under the collar packer of the device 3 and, after the operation of the adjustable hydraulic thief 5, by the flow of well fluid together with debris extracted from the filtration channels of the bottomhole zone of the productive formation due to the creation of a local zone of reduced pressure under the collar packer of the device 3, rushes into the storage container. This operation is repeated several times until the interflow of the well fluid is stopped, which allows high-quality multifunctional well cleaning by means of multiple cyclical depression effects. The presence in the complex of check valves 6, 7 allows you to hold and remove to the surface

- 1 037854 all collected sludge, sediments, mechanical impurities and floating substances that entered the storage container. To drain the drilling fluid from the tubing string in the process of lifting and removing the complex from the well, a knock valve 1 is provided.

The complex of multifunctional well cleaning has a simple design and a minimum number of parts, which provides the possibility of revision in the field without the use of special devices and tools, multiple use during repeated operations.

The described complex of multifunctional well cleaning is distinguished by high-quality cleaning of the productive formation, the bottom of the well, the walls of the production string and the well fluid from mechanical impurities, deposits, sludge and floating substances, the multiple use and long service life of the product, the ability to conduct inspections in well conditions without the use of special devices and tools, lack of high-wear consumables and parts, lack of permanent joints (welded, riveted, glue, etc.).

Claims (1)

CLAIM Complex of multifunctional cleaning of wells, productive formation, well bottom, walls of production casing and well fluid from mechanical impurities, deposits, cuttings and floating substances, including an internal connecting pipe with a collar packer with an upper outlet perforated pipe and a lower slot filter, hermetically connected to the casing The tubing located above the multifunctional cleaning complex has a throttle and a churn valve at the upper end of the connecting pipe, at the lower end the connecting pipe is equipped with an adjustable hydraulic thief, a valve system and a device for eliminating dense plugs, and the collar packer is equipped with a through channel between the upper outlet perforated branch pipe and the lower slotted filter.