RU2242579C2 - Method for operation of tubing pipes in well - Google Patents

Abstract

FIELD: gas extractive industry.

SUBSTANCE: method includes lowering tool set, consisting of tubing pipes, left sub and hydraulic packer-anchor or anchor, placed on lower end of tool. Tool set additionally has well temperature compensator, placed above hydraulic packer-anchor or anchor. Left sub is placed above or below well temperature compensator.

EFFECT: higher durability.

1 dwg

Description

The present invention relates to techniques and technology for producing gas from wells, namely, to a method for operating tubing (tubing) in the gas industry.

There is a known method of operating tubing in wells, including lowering a tubing into the well with a packer-anchor at the end at a predetermined interval, dropping the ball into the cavity of the armature, creating excessive hydraulic pressure under the armature piston, under the action of which the piston pushes the rams onto the cone through the ram holder, ensures the anchors of the rams on the wall of the production casing [1].

This method with the unloading of tubing on the column wall is designed to perform short-term technological operations (separation of the cavity of the column for pumping process fluid, gravel into the reservoir) and cannot be used for long-term operation of the tubing during gas production, since when the pins are cut, the sleeve and ball drop out, the pressure on the piston is removed and the armature dies are released from the column wall. Unloading of tubing (tubing) to the anchor stops. The tubing will be under load of its own weight, which leads to fatigue and premature wear, especially in wells in the presence of hydrogen sulfide and other corrosive liquids.

A known method of operating tubing with unloading on the production casing, including the descent of the tool, consisting of tubing, packer-anchor and liner [2].

The disadvantage of this method is that the anchor is interfaced with the production casing by unloading the tubing supported on the bottom through the liner, and this leads to the formation of a sand plug in the annulus and in the pipes, which entails the inability to carry out circulating operations with the fluid, and other emergency situations , and, as a result, to the cessation of operation of the gas production well.

In addition, when using tubing in this way in wells with high and variable temperature conditions (underground gas storages), they are subjected to curvature, fracture, etc. with the ensuing consequences (accidents, high repair costs, well abandonment).

A known method of operating tubing in wells using a downhole temperature compensator [3].

The disadvantage of this method is that the descent of the tool (tubing) is not complete without the use of anchors based on the bottom, which leads to curvature, kink, cracks, etc. tubing (tubing), which reduces their service life.

The closest analogue (prototype) is a method of operating an STC, which includes the descent of a tool kit consisting of tubing, a left sub and an anchor packer or anchor located at the lower end of the tool [4].

However, in this method there is no use of a downhole temperature compensator, which leads to curvature, kink, etc. The tubing during their operation in wells with variable temperature conditions (underground storage of gas), as well as in deep (over 3000 m) wells with high ambient temperatures.

The aim of the present invention is to increase the service life of tubing, simplifying the technological operations carried out during the operation of gas wells (washing and removal of sand, circulation of liquids and foam, etc.), as well as the regulation of the installation of the bottom of the tubing suspension (filter, instruments ) to a predetermined depth when lowering into the well, replacing, if necessary, tubing without lifting the filter and the borehole temperature compensator to the surface.

The goal is achieved by the fact that in the known method of operating tubing in a well, comprising the descent of a tool kit consisting of tubing, a left sub and a packer — an anchor or anchor located at the lower end of the tool, according to the invention, the tool kit further comprises a downhole temperature compensator located above the packer - anchor or anchor, with the left sub located above or below the downhole temperature compensator.

The drawing shows the General layout of the tool lowered into the well.

The tool arrangement consists of tubing 1, a left sub 2, a borehole temperature compensator 3, an anchor packer 4 and a borehole filter 5 mounted against perforation of the casing 6 in the interval of the productive gas horizon 7.

After lowering the tool kit in the sequence in which it is indicated in Fig. 1, excessive hydraulic pressure is created in the cavity of the packer-anchor or anchor 4, which ensures contact of the armature with the casing and unloading of the tubing from its own weight.

Then, the sleeve is cut off using the ball with the calculated value of the excess pressure, releasing the communication channel in the packer-anchor or anchor for gas to pass from the formation to the surface.

With a variable temperature regime of well operation (underground gas storage), a downhole temperature compensator is included in the work, which eliminates the extension or shortening of the tubing, preventing their bending and stretching.

If you need to replace the tubing, they are removed to the surface using the left sub by rotating them to the right.

For re-lowering of used or replaced tubing (tubing) at its lower end, as a rule, a guide element is provided that facilitates the connection of the tubing with an anchor or a borehole temperature compensator through the left thread of the sub 2.

If it is necessary to remove the entire tool kit to the surface, a pin is provided in the anchor packer or anchor, which, when cut, ensures that the anchor dies are released from the casing wall and the tool is lifted to the surface.

The presence in the proposed invention of the packer-anchor or anchor, mating with the wall of the casing complete with a borehole temperature compensator and a left sub eliminates the liner relying on the bottom and allows you to unload the tubing from its own weight during operation in the well, therefore extend the tubing life, simplify and reduce technological operations, replace the tubing without lifting the packer-anchor or anchor and the borehole temperature compensator to the surface and, as a result e realize his goal.

Using the proposed invention will increase the life of the tubing, simplify the technological operations carried out during the operation of gas wells (flushing, sand removal, circulation of fluids and foams, etc.), as well as regulate the installation of the bottom of the tubing suspension (filter, instruments) depth during descent into the well; replace, if necessary, tubing without lifting the filter and the borehole temperature compensator to the surface.

The economic effect of using the proposed invention, depending on various geological and technological conditions for the operation of the tubing, can be from 20 to 80% in comparison with existing methods of operating the tubing.

Sources of information

1. I.E. Bukhalenko, V.E. Bukhalenko. Equipment and tools for well repair. M .: Nedra, 1991, p. 254.

2. V.F. Budnikov, P.P. Makarenko, V.A. Yuryev. Diagnostics and overhaul of casing strings in oil and gas wells. M .: Nedra, 1977, p. 44.

3. Downhole compensator. UK application No. 2333537, IPC 7 E 21 B 17/07, op. 1999.

4. A.S. SU 212913 A, E 21 B 17/01, 05/13/1968.

Claims (1)

A method of operating tubing in a well, including the descent of a tool kit consisting of tubing, a left sub and a hydraulic packer – anchor or anchor located at the lower end of the tool, characterized in that the tool kit further comprises a downhole temperature compensator located above the hydraulic anchor packer or anchor, with the left sub located above or below the borehole temperature compensator.