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Rudkovska Kristina

Abstract

Introduction

Freeze-ins and breaks are the most common types of technical accidents. These incidents result in premature incapacitation of tools and equipment. Breaks, sweeps and falls of a drilling tool frequently occur at the same time with freez-ins of tool or rotatable drill pipe. At the average it takes from 30% to 80% overhead  to eliminate these accidents.

Actuality

Breaks, sweeps and falls of a drilling tool often attend or preceed a freez-in. Some of the pressing problems in drilling are the development and introduction of the effective methods and tools that can prevent and eliminate such accidents.

Objectives and goals

The main objective of this work is the design of equipment line for elimination of drill string breakdown caused by tool freeze-in.

Main concept of this work is the development of engineering tools to decrease the elimination time of drill string breakdowns.

The problems for achieving the main object are:

-         to develop schematic circuits of tubing catch and hydraulic hammer

-         to account the arrangements to choose the optimal parameters of gripping device of the tubing catch and the parameters of a hydraulic hammer [2, 10].

The subjects of research are designs of existing tubing catches and hydraulic hammers.

Our objects of research are modern engineering tools for elimination of freeze-ins and wringer necks in boreholes.      

Work Approbation

The report on “Development of the external casing catcher” on the VIII all-Ukrainian student conference “Drilling”, 25 of Apil, 2008, Donetsk.

Got the award for an active participation and the best report on theme “Development of technology for the breakdown eliminations in test boreholes” on the IX all-Ukrainian scientific and technical student conference “Drilling”, Donetsk, on 23th of April, 2009.

Contents

The equipment line is developed for the boreholes in the diameter of 93 and 112 millimeters. Arrangement diameter is 89 mm. Device is intended for drill-pipes running a diameter 50 mm.

A complex is rotined on a picture 1.

Hydraulic hammer with a tubing catch go down in an access borehole on the column of pipe drills, here through attachments circulating fluid passes freely. On reaching to the ragged column tubing catch through a centralizing cone covers the ragged bullet.

Duct entering in a tubing catch begins to press on cutter arms 27. Which in same queue through a working core barrel 20 press on a spring 17, raised and flow through a duct in a tubing catch. At the ascent of tubing catch of cutter arm 27 under the function of spring 17 go down and bites a jury duct, keyed on in a cone 30. A cone slides in a body 26 downward and contracts a pump bucket 31, which, broadening, closes off annular distance between a tubing catch and ragged duct. It allows to circulate through a jury column, instrumental in further elimination of freeze-in.

Figure 1 – Complex of attachments

Positions 1-15 is a hydraulic hammer; 16-31 is a tubing catch

Further through the column of pipe drills a ball clack is discharged 2, he occupies a condition in the upper bend of valvular box 3 hydraulic hammers.

The current of fluid passes through windows in a clutch 7 and further to on annular distance enters lower cavity of core barrel 8 under a piston 9. Due to pressure of fluid of Р on a piston, force of R_в is formed in the core barrel of device R_в = P (f_п – f_ш), which provides up-stroke of piston-bullet (f_п is an area of piston 9; f_ш is an area of boss 10).

As on a flap 2 force of operates at this time R_к = Pf_к (f_к is an area of floor of globule), pinning him against the upper bend of valvular box 3, butterfly 4 remains immobile. At motion of piston 9 upwards simultaneously bosses 11 move on notch grooves 12, executed in the butt of butterfly 4. There is contraction of spring 13.

Driving the spacing interval of working stroke of S, piston 9 buffets on a butterfly 4. Due to blow and energy of the compressed spring energy 13 flap 4 will move upwards. Due to a pushrod 14 a ball-shaped induction-valve 2 will be opened, moving from the central condition of upper bend aside. Fluid will begin to enter both overhead and in lower cavities of core barrel 8. А bullet 5 will continue up-stroke amain to hitting with an overhead anvil 15. Thus he will drive a spacing interval (S₁–S), his drop energy must be more than stagnation force on a way (S₁–S).

Motion of piston will begin downward after it, that will be provided by force R_н = P (f_ш – f_шк), (f_шк is an area of boss of butterfly 4). This force is resulting by force and is conditioned by the presence of differential geometry of piston at operating on him of pressure, both from overhead and from lower flanks.

At motion of piston 9 downward, flap 4 saves an overhead condition due to force of pinning of him to the lower end face of valvular box 3. After passing of spacing interval of S bosses 11 buffet on the butt of flap 4, due to what both flaps 2 and 4 will move downward. Access of fluid in the overhead cavity of core barrel 8 discontinued. Fluid will enter only lower cavity of core barrel. A bullet 5 due to the accumulated energy will continue motion downward to hitting with a lower anvil 6. The cycle of work of hydraulic hammer will repeat oneself.

During work of hydraulic hammer jointly with a tubing catch, tuning the cycle of work will be debugged with the capability of inflictings blows only on an overhead anvil.

If it be impossible cutout of jury column, a complex is released from a caught-on duct.

For this purpose joint is broken an a counter-clockwise rotation hydraulic hammer and come out on a floor. In an access borehole bleeds a column, tack to the tubing catch. Further through a boring cake in pipe drills discharge a globule which blocks off a communicating aperture declivous boss 19. Pressure of fluid on a globule compels to compress spring 22 and tube 21 begins to move downward opening apertures in boss, through them fluid gets in the working cavity of core barrel 20, moving him upwards in relation to an immobile piston 23 to the checking apertures in the foot of core barrel 20. Whereupon fluid gets in a body 26 tubing catches. Moving upwards, core barrel 20 carries away with itself bight cutter arms 27, which rid of caught-on duct, a cone slides upwards to the circlip 29 due to the return of pump bucket 31 in an initial condition. After disengagement a tubing catch is come out on a floor.

Consequences

The principle charts of attachments (hydraulic hammer of double-action with one controlled cavity and outward casing catcher) are in-process offered for elimination of precipices, caused the freeze-ins of drill stem.

The calculations of rational characteristics of hydraulic hammer and tubing catch are conducted for the best jury column and cutback of time holdup on elimination of freeze-in.

List of the utilized literature

1. Волков А. С. Буровой геологоразведочный инструмент / А.С. Волков. – М.: Недра, 1979

2. Ганджумян Р.А. Практические расчёты в разведочном бурении / Р.А. Ганджумян. – М.: Недра, 1977

3. Гончаров А.Е. Пособие бурильщику и мастеру по предупреждению и ликвидации аварий и осложнений при разведочном бурении / А.Е. Гончаров, В.М. Винниченко. – М.: Недра, 1987

4. Калиниченко О.И. Забойные буровые машины: учебное пособие / О.И. Калиниченко, П.В. Зыбинский. – Донецк: ДонНТУ, 2006. – 222 с.

5. Коломоец А. В. Современные методы предупреждения и ликвидации аварий в разведочном бурении / А.В. Коломоец. – М.: Недра, 1977

6. Пустовойтенко И.П. Аварии в бурении / И.П. Пустовойтенко. – М.: Недра, 1965

7. Авторское свидетельство СССР №927960, Кл. Е 21 В 31/18, 1980

8. Информация об инструменте для ликвидации аварий и осложнений, режим доступа к статье: http://www.drillings.ru/likvidacia

9. Информация о методах ликвидации прихватов, режим доступа к статье: http://www.dobi.oglib.ru/bgl/2726/25.html

10. Информация о теории и расчете рабочих процессов гидроударных машин, режим доступа к статье: http://www.dobi.oglib.ru/bgl/2117/246.html

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