DE1235236B - Resilient, compliant drill rod insert - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

E21b

German class: 5 a-17/04

Number: 1235 236

File number: D 50124 VI a / 5 a

Filing date: May 14, 1966

Open date: March 2, 1967

The invention relates to a resiliently flexible insert for drill rods, which is particularly suitable for installation is determined between the drill string and the drilling tool of a roiary pipe string. By Such inserts will extend the life of the tool and that of the individual drill pipes or tubes Collars connecting devices thereby increases that the magnitude of the stresses that are applied these connection points during the up and down movement of the rotating on the borehole bottom Tool occur during the drilling process is reduced.

With such resilient drill string inserts, apart from a tensile stress-elongation ratio, which is low compared to that of the rest of the strand, the transmission of the torque, the absorption of stresses occurring in the longitudinal direction during tension and compression and ensures the supply of flushing fluid to the tool required for the drilling process be. To accomplish this, many insert designs have been proposed, e.g. B. made of metal Devices in the form of coil springs and long thin tubes made of rubber Links in the form of sleeves and blocks, and sealed piston-cylinder assemblies that operate with liquids or shock absorbers working with viscous liquids. Disadvantages of these known devices exist, for example in that some of these devices have particular types of seals and keyway arrangements are needed. In other known devices, the life of the device is very long or their axial length excessively large.

In accordance with the invention, a resilient drill string insert is desired to be long-lived and proportionate short length can be created in which the stretching stresses only from metal parts are included and in which all seals exposed to pressure loads and furthermore Keyway arrangements and similar, highly wear-exposed parts are eliminated.

According to the invention, this is achieved in particular in that a Corrugated pipe is used as an axially resilient element.

The corrugated pipe can consist of a number of annular disks arranged in pairs, which, for example by brazing or welding, on their inner and outer peripheries by inner and outer Rings are connected or made in one piece. This construction is sufficient Resilient drill rod insert

Applicant:

Drilco Oil Tools, Ine, Midland, Tex. (V. St. A.)

Representative:

Dr.-Ing. K. Boehmert

and Dipl.-Ing. A. Boehmert, patent attorneys,

Bremen, Feldstr. 24

Named as inventor:
William Robert Garrett,
Midland, Tex. (V. St. A.)

Strength to both transmit torque and take up axial expansion and further the supply of rinsing liquid under high pressure from the pipe string to the tool allow. The rigid casing pipe, which is concentric to the corrugated pipe and serves to absorb bending moments, that this preferably surrounds, is rigid at its end with the one above the corrugated pipe Part of the insert connected and telescopically surrounds a cylindrical bearing surface at its lower end the part of the insert lying below the corrugated pipe. This storage space is sufficient long in order to avoid bending moments occurring between it and the jacket pipe without impermissible bending to be taken from the jacket pipe and storage area. The jacket tube is made so rigid that it takes the bending moment can transmit without impermissible deformation. It also serves as a housing that holds the Keeps corrugated pipe out of contact with the borehole wall.

The corrugated pipe used in the new insert is made of rigid material despite its bellows-like shape made and not made of flexible materials such as cloth, paper, leather and similar thin-walled flexible fabrics from which concertina-shaped bellows and other expandable devices are made are. The new insert also differs advantageously from a straight tube, which only comes with contract due to the stress-strain ratio of the metal from which it is made. Of the New use also differs in an advanced way from a cylinder spring, which because of the gaps present between the turns cannot serve as a liquid line. Ge

709 517/50

3 4

compared to devices with rubber and elastic converge below. Adjacent upper and lower Shear material existing parts, it has to form the front surfaces 20, 21 of adjacent annular disks part that high temperatures do not work so a pointed and adjacent peripheral surfaces can have an unfavorable effect. 22, 23 of these disks an obtuse angle under-According a preferred embodiment is 5 of each other. The rings 25 and 26 point to their inside of the corrugated pipe another concentric ren and outer circumference pairs of under blunt Tube provided that the corrugated tube from touching angles to each other extending conical surfaces with the rinsing liquid protects the inner tube, the slope of which is that of the surfaces 22 and 23, respectively speaks to the part lying above the corrugated pipe, with which it is connected by brazing of the insert and is telescopic with io. The inner peripheral surface 22 of the lowermost ring dem The part of the single disk 16 lying below the corrugated pipe is attached to a correspondingly conical set in touch. Further, the gap is the outer peripheral surface of an upwardly protruding one the jacket pipe and the corrugated pipe with lowing part 30 of a pipe 31 soldered. The Ringseinem Lubricant filled, d. H. one eating slices are thick, d. that is, its thickness is more Contact of the corrugated pipe with the jacket pipe accounts for 50% of the radial distance between their inner and outer sides guarding liquid. Here, outer circumferential surfaces can be used at the lower end. It can be seen that the of the insert a sliding seal provided large areas of the inner and outer circumferences, which prevents the liquid from leaking out. surfaces of the annular disks 16 and the associated

In the drawings is Neten surfaces of the inner and outer rings 25 and

Fig. 1 is a partially shown in cross-section elevation of 20 26, the shear stresses in the brazed

a preferred embodiment of the invention, reduce connections. With good soldering and

FIG. 2 shows a large-scale cut-good soldering material can achieve greater torques than

view of a corrugated pipe with the maximum required torque of 350mkg shown in Fig. 1

Training to be transmitted through the corrugated pipe. Under hard

F i g. 3 a large-scale sectional soldering, here every metallic connection is made of metal.

view of one in the embodiment nadh F i g. 1 understood tall surfaces, in which usually one of

used seal, the metal of the surfaces to be connected differ -

4 shows an elevation, partly in section, of one of the connecting metal used and the connecting

further preferred embodiment of the invention metal, but not the metals to be connected,

dung, 30 is brought into a liquid state. So both

5 shows a cross-section shown on a larger scale, for example copper, copper alloys, silver solder and

cut through the wall of the nickel-silver shown in Fig. 4 to connect steel parts.

Corrugated pipe, det. The ring disks 16 and the rings 25,

Fig. 6 is a view similar to Fig. 5 with ab- 26 are preferably made of steel with a modified one Shape of the corrugated pipe, 35 quenching temperature below the melting point

7 is a vertical sectional view through one of the solder;

one-piece corrugated pipe design and In the lower end of the pipe is the upper end

8 and 9 are vertical partial sections of screwed through set 32 of a tube 33, the lower one

Corrugated pipe constructions produced by welding. End at 34 to an internally threaded one

The in Fi g. 1 shown resilient drilling 40 sleeve 34 is expanded.

rod insert has a connecting piece 10, des- A jacket tube 40 is with its upper end

sen outside and inside diameter that of the drilling outside screwed onto the pipe socket 12 in such a way,

the drill pipe or the drill collar. That it is at the middle part of the connector 10

Connection piece rests with an upwardly projecting one and forms a rigid connection therewith.

Threaded extension 11 and one extending from its middle 45 The jacket pipe 40 surrounds the corrugated pipe 17 even then

leren, the largest diameter part at a distance, if this is under pressure

downwardly extending pipe socket 12 is provided. is compressed.

The pipe socket 12 is provided with an internal thread 13, the lower end 41 of the jacket pipe 40 is tele-

into which the upper threaded extension of a tube 14 is scopically attached to the cylindrical outer surface 42 of the

is screwed. so tube 31 out.

The tube 14 has a lower, inwardly to the lower end of the jacket tube 40 is a set part 15 of smaller diameter. At safety device 50 with an inside before this Part 15 is the top of a number of thick, standing radial flange 51 screwed together, the between a kind of corrugated pipe 17 forming, made of metal see a stop surface 52 at the lower end of the existing annular disks 16 on their inner circumference 55 tube 31 and one through one between the upper attached by brazing. Like F i g. 2 shows that the shoulder 32 and the central part of the tube 33 run forward the upper and lower surfaces 20 and 21 is seen shoulder formed stop surface 53, as well as the inner and outer urof angsseiten 22 and the device 50 thus allows that the 23 of each washer 16 conical, and also the outer corrugated tube 17 expands and contracts, prevents Circumferential surface of the part 15 on which the uppermost ring 60 but a complete separation of the parts and over-washer is soldered is conical. If the corrugated pipe breaks, it will have a tensile cross-section the washer is rectangular. and longitudinal compressive forces.

The outer circumferential surfaces 23 of the annular disks, which are located above and below the flange 51-

16 are formed by brazing with outer rings 25 and sections 60 and 61 of device 50

the inner circumferential surfaces 22 in the same way with C5 telescopic guides on the cylindrical FIa-

inner rings 26 connected. Superimposed surfaces 62, 63 of the pipes 31 and 33. For a sufficient

Ring disks 16 are arranged alternately so that support should correspond to the length of the guide

that their conical surfaces upwards or after the cylindrical surfaces at least equal to that

5 6

Be the diameter of the cylindrical surface. In the In F i g. 4 is another preferred embodiment shown Embodiment, this minimum er form of the invention is shown only in the following

considerably exceeded. Points of the embodiment shown in Fig. 1

F i g. 3 shows that the lower end 70 of the Vorachform deviates:

device 50 has a large inner diameter and 5 1. The inner tube 80 is omitted;

together with the outside of the tube 33 a ring 2. The inner rings 26 of the corrugated tube exist

chamber 71 forms. In this chamber 71 is an annular one piece with the annular disks 16 ', such as

shaped rubber seal 72 movably arranged, best from F i g. 5 results;

which has a metal core 73. The seal is 3. The washers 16 'are towards the

tapered at their upper and lower ends with the inner and center of the discs, d. i.e., they are

outer lips 74,75, 76,77. thicker outside than inside;

Below the seal 72 is an end ring 4. The seal chamber 71 and the seal 72

70 α into the lower end of the device 50 and the lubricant is no longer needed.

screwed, the entry of impurities, and the above-mentioned clearance is great.

in the chamber 71 prevented. The closing ring serves 15 selects to reduce the wear effect of the flushing fluid

also as a holder for the seal, although this speed can be reduced, which in F i g. 1 of the

stuck in their position. Lubricant fills the occupied space.

Above the seal 72 is located in the corrugated pipe according to Fig. 4, the flushing

Chamber 71 and in which between the jacket pipe liquid as a lubricant, which prevents the weIl-

40 and the device 50 on the one hand and the pipes 20 pipe on the jacket pipe prevented. The one-piece

33 and 31, the corrugated pipe 17, pipe 14 and pipe with the inner rings existing washers

Approach 12 on the other hand existing game a lubricating have the form of forked toroidal rings 90, the

medium, i.e. a light mineral oil that is less sensitive to scuffing against the abrasive

prevented by jacket pipe and corrugated pipe 17. The kung of the flushing liquid are called the brazed ones

Seal 72 also prevents flushing fluid from entering the connections between the inner rings and

Lubricant. The seal follows the ring disks according to FIG. 1, making the inner tube

stretching and contraction of the lubricant 80 can be omitted. Because of the size-

means, since it changes in the rinsing liquid strength of the one-piece construction according to FIG. 4th

The cross-section is required for this arrangement

Lubricant in the chamber 71 up and down 30 the connection point between the annular disks 16

can move. and corresponds to the inner ring 26 for transmission

Depending on the size of the torque required in the previous paragraph, not too great sentence mentioned game results in a different as with the arrangement according to FIG. 1. Rather great damping of the spring action of the corrugated pipe can, as already mentioned, the cross-section according to 17. Preferably, the game is so large that the 35 taper inside. This becomes the tension lubricant no damping effect, but only expansion ratio smaller, so that the corrugated pipe has a lubricating effect and a metal-on-can be shorter. By shortening the corrugated pipe Metal contact between the corrugated pipe 17 and the casing and the omission of the seal will also damage the pipe 40 prevented. total length of the embodiment shown in FIG

In order to protect the interior of the corrugated tube 17 from the cord 40 smaller than that according to FIG. 4 is essentially the same within and concentric to the corrugated pipe as in the insert of FIG.
an inner tube 80 is arranged, the upper end of which is screwed into the lower end of the part 15 in the case of the resiliently flexible insert according to FIG. This is the bellows-like corrugated pipe between a first lower end of the inner pipe 80 forms a telescopic 45 tubular component with the threaded sleeve 34 and see guide 81, which rests on a cylindrical bearing a sliding surface and surface 82 of the pipe 31 arranged above this. The inner tube serves a second tubular jacket with the jacket, in addition to jacket tube 4, to transfer bending torque extension 11 and a telescopically engaging jacket tube 40 from the upper end of the resiliently flexible jacket tube 40 to its lower end. 50 sorted.

In summary, it should be noted that the Well- F i g. 6 shows a further modification of a corrugated pipe at its upper and lower end with pipe, in which half of the existing in the corrugated pipe shaped connecting elements, namely the soldered connections are eliminated in that closing piece 10 and the tube 14 above and the tube man the lower ends of the rings 25 'in one piece Ren 31 and 34 below, provided and inside through the 55 with the toroidal rings 90 'executes. Further Pipe 80 and outside through the jacket pipe 40 and the annular disk 16 'is integral with the part 15' is protected by the lubricant. of the pipe 14 'and the lowest ring 9ö "

In operation, sleeve 34 is usually either integral with part 30 '. Apart from that, entdirekt or the corrugated pipe according to FIG. 1 speaks via an intermediate piece with the drill. 6 after the corrugated pipe tool and the threaded attachment 11 either directly 60 Fig. 5.

or via a pipe connector with the lowest taking into account factors such as Her-drill collar of the drill string connected. The corrugation cost, strength, service life and outlet pipe 17 reduces the size of the drill string and the possibility of using the whole corrugated pipe in one the stresses occurring in the drilling tool, to be manufactured in one piece (Fig. 7). So you can in one which, despite the pressure of the heavy drill string 65, has internal and external grooves Rapid lifting of the drilling tool allows it to rotate so that annular disks 116 are formed which if this is connected via an upwardly projecting part by inner and outer rings 125,126 rolled away from the bottom of the borehole. are. These flat ring disks can be easily

Claims (13)

produce. The bottoms of the grooves can be rounded off by arcs of a circle with a diameter corresponding to the distance between the disks. The corners 118 at the outer groove ends would then also be rounded. The tubes 14 and 31 of FIGS. 1 and 4 could then consist of one piece with the corrugated tube, as shown at 114 and 131 at the upper and lower end of FIG. 7 is shown. In place of the ring disks and rings formed by brazing according to FIGS. 1 and 2 or according to FIG. 7 corrugated pipes made in one piece or the one shown in FIG. 4 and 6, the corrugated tubes can also be formed by welding together washers and rings. FIG. 8 shows an embodiment with fork-shaped rings 290 which, similar to the rings 90 of FIG. 5 consist of two ring disks and an inner ring connecting them. The rings 290 are connected by outer rings 225 to which the rings 290 have spaced apart flanges 226. The rings 290 have protruding lips 291 to which the outer rings 225 are connected by welds 300. F i g. 9 shows one of the in FIG. 8, in which the lower ends of the outer rings 225 'consist of one piece with the upper parts of the fork-shaped rings 290' and the spacer flanges 226 have been omitted. All of the above-described types of corrugated pipe can be used in the resilient inserts shown in FIGS. Patent claims: 1. Resilient drill pipe insert, in which the load on the drilling tool takes place via an elastic intermediate member, characterized by an in a jacket tube (40) arranged corrugated tube (17) as an axially resilient element. 2. drill rod insert according to claim 1, characterized in that the between the casing tube (40) and corrugated tube (17) lying annular space is filled with liquid, of which when squeezing of the corrugated pipe and the resulting reduction in the annular space a part through the telescopic connection after a Reservoir chamber (71) can flow off. 3. drill rod insert according to claim 2, characterized in that in the ring-shaped Reservoir chamber (71) a sliding ring seal (72) is provided, the cross-section of which corresponds to the chamber cross-section. 4. Drill rod insert according to one of claims 1 to 3, characterized by a tubular safety device (50) which is connected to the casing tube (40) and which has a protruding flange (51) on its inner wall, which is located between two axially spaced stop surfaces (52 , 53) , which are provided on the lower connection part (31, 34) . 5. Drill rod insert according to one of claims 1 to 4, characterized in that the corrugated tube (17) consists of a number of annular disks (16) arranged in pairs, which are connected at their inner and outer peripheries by inner and outer rings (25, 26) are. 6. drill rod insert according to claim 5, characterized in that the annular disks (16) are conical and the annular disks of each pair have opposite conicity. 7. drill rod insert according to one of claims 5 and 6, characterized in that the thickness of the annular disks (16) is at least half as large as the radial dimension of the disk and the rings (25, 26) connected to the annular disks (16) by brazing are. 8. A drill rod insert according to any one of claims 5 to 7, characterized in that the inner and outer peripheral surfaces (22, 23) of the annular disks ( 16) which are connected to the rings (25, 26) are conical faces which meet at obtuse angles. 9. drill rod insert according to one of claims 5 to 8, characterized in that the pairs of annular disks are combined with the inner ring to form forked rings (90, 290) . 10. drill rod insert according to claim 9, characterized in that the inner Sections (16 ') of the forked rings are thinner than the outer sections of these rings. 11. A drill pipe insert according to claim 9 or 10, characterized in that the outer rings (225) have inwardly facing flanges (226) which are in contact with two adjacent forked rings (290) , and that these rings (290) on the outer circumference are provided with protruding lips (291) to which the outer rings (225) are connected by welds (300) . 12. drill rod insert according to claim 9 or 10, characterized in that each forked Ring (90) with one of the outer rings (25 ') consists of one piece. 13. drill rod insert according to one of claims 1 to 4, characterized in that the Corrugated pipe (17) consists of a tubular body in which inner corrugations are formed and outer grooves are screwed in. Considered publications:
German Auslegeschrift No. 1165 519;
U.S. Patent No. 2,756,022. 1 sheet of drawings 709 517/50 2.67 © Bundesdruckerei Berlin