RU2543226C2 - Method for enlargement and reaming of well shaft - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: method for enlargement and reaming of a well shaft is implemented by means of a tool including a hollow housing with a flushing hole on an end face; the lower part of the housing has end and side surfaces, and the upper shank part of the device has the shape of a cylinder ended with a thread; the lower part of the housing consists of a pilot centring part having a cylindrical shape, on the side surface of which there are flushing ports, and a diverging part. As a tool, a bit is used, the lower part of the housing of which has end and side working surfaces reinforced with armour, and the diverging part of the lower part of the housing is provided with blades and has the shape of cylinder of larger diameter, in the inter-blade space of which flushing ports are arranged.

EFFECT: excluding deviation from direction of the pre-drilled shaft and improving operating properties.

7 cl, 6 dwg

Description

The invention relates to methods of expansion - increasing the diameter and calibration of the wellbore.

A known method of expanding and calibrating a well using diamond crowns and / or diamond reamers using the principle of abrasive action (Ryabchikov S.Ya., Khramenkov V.G., Brylin V.I. Technology and technique for drilling exploration and geotechnological wells: Tomsk Polytechnic University - Textbook. - Tomsk: Publishing House of the Tomsk Polytechnic University, 2010. - 494 pp. - pp. 39-45, 48-50).

The disadvantages of this method include:

- lack of centering along a pre-drilled wellbore, which causes a deviation from the well profile;

- random arrangement of diamonds in the matrix makes it difficult to predict the removal of rock from the walls of the well;

insufficiently reliable fixing of diamonds in the matrix, which leads to their loss during operation and premature tool wear.

There is a method of expanding and calibrating a well with a cone bit and / or cone reamer of cutting-chipping, crushing and crushing-chipping action (Ryabchikov S.Ya., Khramenkov V.G., Brylin V.I. Technology and technique for drilling exploration and geotechnological wells: Tomsk Polytechnic University - Textbook. - Tomsk: Publishing House of Tomsk Polytechnic University, 2010. - 494 pp. - pp. 45-47, 48-50).

The disadvantages of this method are:

- like the previous analogue, the lack of centering along a pre-drilled wellbore, which leads to a deviation from the well profile;

- a high level of vibration, since the used cone tool is a crushing-shearing tool;

- decrease in tool life due to the presence of bearings with rolling, sliding, or combined bodies in the bearings of roller cones, since spells may occur;

- low performance - wear resistance and mechanical drilling speed.

Closest to the proposed method according to the principle of operation, is a method of expanding and calibrating a wellbore selected as the closest analogue using a tool containing cutters including a hollow body with a washing channel along the tool axis and a washing hole at the end, the lower part of the body has an end face and lateral surfaces, and the upper tail part of the device has the shape of a cylinder ending with a thread, and the lower part of the housing consists of a cylindrical pilot center generating portion on the side surface of which flushing channels are formed, and a spreading part (Russian patent RU 2276246, C2, 10.05.2006, only 12 p .: claim 1, 2).

The use of this invention allowed to solve the problem of centering the tool in the wellbore and to exclude deviations from the direction of the pre-drilled barrel, however, it is inherent in all the other disadvantages of the cone tool listed above.

The objective of the invention is to develop a method for expanding and calibrating a wellbore, the implementation of which improves performance (penetration at a bit and mechanical speed).

The problem is solved in that the expansion and calibration of the wellbore is carried out using a cutting-shearing tool - a bit, including a hollow body with a washing channel along the axis of the tool and a washing hole at the end, the lower part of the body has end and side working surfaces reinforced with weapons, and the upper tail part of the device has the shape of a cylinder ending in thread, the lower part of the body consisting of a cylindrical-shaped pilot centering part, on the sides on the surface of which washing channels are made and of an expanding blade part having the form of a cylinder of a larger diameter, in the inter-blade space of which washing holes are located.

A flushing channel may be provided on the end working surface of the pilot centering portion of the lower part of the housing.

As armaments, carbide cutters and / or PDC diamond cutters and / or carbide cutters impregnated with diamond chips can be used.

On the front working surface of the pilot centering part of the lower part of the hull, carbide cutters are preferred as weapons.

The lateral working surface of the pilot centering part of the lower part of the housing can be reinforced with inserts of any wear-resistant material (PDC, hard alloy, hard alloy with impregnated diamond chips, etc.).

On the expanding lobed part of the lower part of the hull, it is preferable to use diamond PDC cutters as weapons, which are much less prone to abrasion.

The expanding blade part of the lower part of the housing can be reinforced with inserts of any wear-resistant material (PDC, hard alloy, hard alloy with impregnated diamond chips, etc.).

The number of blades and cutters is determined by the geometric dimensions and working conditions, and should ensure maximum efficiency of the process of expansion of the wellbore.

When implementing the method - the work of the bit to expand and calibrate the wellbore, due to the weapons available on the bit, the load on each unit of weapons is uniformly distributed and a uniform removal of the rock is ensured, which significantly increases the life of the bit (sinking to the bit) and the mechanical expansion speed and well calibration. To create a cutting action, an axial load of an order of magnitude less is required than for cone bits at the same or high speeds. The increase in the mechanical speed of the expansion and calibration process is also due to the presence of a sharp cutting edge of the weapon, its low wear rate and the effect of self-sharpening during drilling.

The presence of weapons on the end working surface of the pilot centering part of the lower part of the hull additionally provides the possibility of drilling blockages and traffic jams formed previously destroyed rock.

Thus, the above information provides a solution to the problem to which the claimed method is directed, namely, improving performance (penetration on a bit, mechanical speed).

The application contains all the means by which the implementation of the method is possible.

The essence of the technical solution is illustrated by drawings of a special bit in various preferred variants of its implementation and its description.

Figure 1, 3, 5 shows a bottom view of the device in the preferred variants of its implementation.

Figure 2, 4, 6 shows a General view of the device in the preferred embodiments of its implementation.

In Fig.2, the device consists of a hollow body 1 with a flushing channel located inside the body along its axis (not shown in the figures). Conventionally, the device is divided into two parts: the lower part I reinforced with armament and the upper tail part II part of the device in the form of a cylinder ending in thread. The lower part of the device consists of a cylindrically shaped pilot centering part Ia, and an expanding blade part Ib, which has the shape of a cylinder of a larger diameter. The pilot centering part Ia with a flushing channel 6 and a flushing hole 4 at the end is reinforced with armaments in the form of carbide (in this embodiment) cutters 2 at the end to drill blockages and plugs formed by previously destroyed rock. The expanding blade part Ib is designed to expand and calibrate the wellbore, made in the form of all-milled (in this embodiment) blades reinforced with armament in the form of cutters 3, flushing holes are made in the inter-blade space 4. The lateral working surface of the pilot centering part with flushing channels 6 and expanding the blade part of the lower part of the housing is reinforced with inserts 5 of wear-resistant material (in this embodiment).

The method is as follows.

Axial force and torque are transmitted from the drill bit pipe. Under the influence of these forces, the chisel 3 cutters penetrates into the rock and destroys it. The flow of drilling drilling fluid, leaving through the drilling holes 4, washes the bottom and removes particles of the destroyed rock from the bottomhole zone, while simultaneously cooling the cutters. Thus, the bit deepens into the rock, and expands the existing wellbore. The pilot centering part Ia of the lower part of the body centers the bit along a pre-drilled wellbore, excluding deviation from a given direction.

A specific example of the implementation of the method.

The method of expanding and calibrating a wellbore using a bit in the embodiment shown in FIGS. 1, 2 was tested during drilling of well No. 1202 IG, the Sibaysky branch of Bashkirgeologiya OJSC, Vishnevsky section. The work on expanding and calibrating the walls of the well was carried out in the following rocks: sinter-block tuffs of andesite composition and quartz-plagioplase dacites with a bit produced by NPP Burservis -BS-76/93 ED 613-001. Extension of 76 mm well to 93 mm. The following results are shown - mechanical speed 2.5 m / h, maximum penetration per bit 200 m, there are no deviations from the original profile of the well.

Under similar operating conditions, the speed of expansion of the wellbore with a cone bit did not exceed 0.8 m / h, and the maximum penetration per bit was 13 m.

Claims (7)

1. A method of expanding and calibrating a wellbore using a tool, including a hollow body with a flushing channel along the axis of the tool and a flushing hole at the end, the lower part of the body has end and side surfaces, and the upper tail part of the device has the shape of a cylinder ending with thread, and the lower the housing part consists of a cylindrically shaped pilot centering part, on the flank surface of which flushing channels are made, and an expanding part, characterized in that as a tool A chisel is used, the lower part of the body of which has working end and side surfaces reinforced with weapons, and the expanding part of the lower part of the body is equipped with blades and has the shape of a cylinder of larger diameter, in the inter-blade space of which there are washing holes. 2. The method according to claim 1, characterized in that a flushing channel is made on the end working surface of the pilot centering part of the lower part of the bit body. 3. The method according to claim 1, characterized in that carbide cutters and / or PDC diamond cutters and / or carbide cutters impregnated with diamond chips are used as armaments for the bit. 4. The method according to claim 1, characterized in that on the end working surface of the pilot centering part of the lower part of the bit body, carbide tools are used as weapons. 5. The method according to claim 1, characterized in that the lateral working surface of the pilot centering part of the lower part of the bit body is reinforced with inserts of wear-resistant material. 6. The method according to claim 1, characterized in that on the expanding blade part of the lower part of the bit body, diamond PDC cutters are used as weapons. 7. The method according to claim 1, characterized in that the expanding blade part of the lower part of the bit body is reinforced with inserts of wear-resistant material.

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