CA2337500A1

CA2337500A1 - Tubing injector

Info

Publication number: CA2337500A1
Application number: CA002337500A
Authority: CA
Inventors: Roger W. Fincher; James W. Macfarlane; Peter Fontana
Original assignee: Baker Hughes Inc
Current assignee: Individual
Priority date: 1998-08-03
Filing date: 1999-07-15
Publication date: 2000-02-17
Also published as: AU5107699A; WO2000008296A1

Abstract

The present invention provides a tubing injector for moving reeled tubing in to and out of wellbores. The injector includes a pair of endless tracks the hav e a through opening therebetween for the passage of the tubing therethrough. A plurality of engagement assemblies are carried by the endless tracks. Each assembly on one track has a corresponding assembly on the other track. As th e track is moved, the corresponding assemblies face each other. The corresponding assemblies have lateral latches that lock. Gripping members in each such assembly engage the tubing to move the tubing. The gripping force is generated internally within the assemblies rather than being applied externally.

Description

._ . . . .... ~. .. ._ . _ _ _ . _. ._ .. _1T'_. ~-. ~ _ _ .~"_~ ' . ! m ~-:bb as tu-~_ _ __+~'~ ~'v z~;~~4~5: d 4 TUBING 1TIJECTOR t>Z'ILIZ1NG ENGAGEMENT ASSEMBLIES FOR MOVING A
TUBING INTO A WELLBORE
1 BACKGROUND ~ INYENTrON

2 Field of the Invention 3 This invention relates generally to tubing irij oction systems ;for oilfield operations 4 and more particularly to an injector that utilizes engagement asscrublies to move tubing relative to an oilfield destination, such as into and out of a w cllbore.
6 Desc lion ~f ~g Related 7 Tubing (either coiled tubing or j ointed tubia~ is commonly used as tho tubing of 8 a work string for performing a variety of wellbore operations. The work string may be 9 a drill string having a drill bit at the bottom, a completion string used for completing a wellbore or a production string for transporting formation fluid to the surface. The tubing 11 may be continuous and of tmiforaa outer diameter. One or more tubing injectors at the 12 rig site are used to move the tubing xelativ a to an oilfield destination, such as into and out 13 of the wellbare.
14 Conventional injectors use an endless chain that carries gripping members which engage ttic tubing by applying lateral force on members via a pressure plate to grip the 16 tubing. For deep w ell operations and for large diameter tabings, increased lateral force 17 moat be applied to the members which increase wear arid reduces reliability. German 18 patent 23,5476? shows an endless track type device that laterally moves a tubing. Each 19 ltackincludes a plut~ality of engaged devices which move the tubing. Other endless track znjector heads arc also Down in the art, Thv present invention provides a novel injector AMENDED SHEET ~~ ~~~

__ .._~..._..... .. . . v v .
. . . - <.v - a . ~ ~ J LOt7 Oa 1 V-n t~p~ t$~ -~;j~y4g(jp : # 'J
.... ._._.__. _ _. -...:. . -... .-- _._ ____ _-i -. __ __ __ . . __ - i system which utilizes eagagcment assemblies carrying the gzipping members to grip and _ 2 move tbc tubing.
3 'ibis invention enables the giipping force to be generated within the interlocked 4 assemblies and thus eliminate the need for the application of external latcra! force on the S engageraent assemblies or gripping mcnnbers to ef>'cct the gripping of the tubing, thereby increasing lift capability, reducing wE~ and increasing reliability.
cR.Y~flF THE )~VENTION
g The present invention provides a tubing injector for moving tubing relative to an 9 vilfxeld destination, such as into and out o~ wellbores. The injector includes a set of endless tracks which have a through opening therebttwecn foe' the passage of the tubing 11 therethxough. A plurality o~ engagement assemblies are carried by the endless tracks.
12 Each assembly on one track has a comsponding assembly on the other track.
As the 13 track is moved, the corresponding assemblies face each other. The corresponding 14 assemblies have interloclang mechanism which interlock with each other as such assemblies enter a gripping zone and move the tubing and unlock as such engagement 15 assemblies leave the gripping zone. The gripping force is g~erated internally of the l7 engagement assemblies.
18 Examples of the more important features o~ the invention thus have been 19 summarized rather broadly in order that detailed descriprion thereof that follov~~s may 24 better be understood, and in ordtt that the contributions to the art may be appreciated.
21 ?here are, of course, additional featuresvfthc inveadonthatvvillbedescn'bedhereinaftar 2~, and which will form the subject of the claims appended hereto.
554-12585-PC:T

. - .... _ .. . ... _..~....~.. _.. _. . a~._...~.:~_..~, qMENDED SHEET ...__.

2 For detailed understanding of the present invention, reference should be 3 made to the following detailed description of the preferred embodiment, taken 4 in conjunction with the accompanying drawings, in which like elements have been given like numerals and wherein:
6 FIG. 1 shows a schematic of a tubing injector containing tubing 7 engagement assemblies driven by a transport mechanism according to the 8 preferred embodiment.
9 FIGS. 2A-2B show an elevation view and a horizontal section of the engagement assemblies, gripping elements and a compression energizing 11 element according to the present invention.
12 FIGS. 3A-3B show a cross section of a pair of engagement assemblies 13 in latched relationship to grip the tubing and move the tubing in the preferred 14 direction and a lateral latch having a pair of faces, one face on the gripping member and a corresponding face on the engagement assembly.
16 FIG. 4 shows the operation of the injector via the movement of the 17 engagement assemblies.

The present invention provides an injection system for the moving of 21 tubing relative to an oilfield destination, such as in and out of a wellbore. In 22 general the system uses matching sets of engagement assemblies to grip the 23 tubing and produce a lateral latched arrangement around the tubing. The 24 assemblies then move the tubing in the preferred direction through the use of a suitable transport mechanism, such as a drive system of chains and sprockets.
26 The tubing may be continuous tubing, such as coiled tubing or jointed 27 tubing of predetermined lengths connected by a threaded connection. In r CA 02337500 2001-O1-15 ~

1 addition, the tubing handled by the injector may be of various diameters from 2 one oilfield destination to the next, and along a tubing string among segments 3 of the tubing and/or threaded connections and equipment carried on the tubing 4 such as bottom-hole assemblies and stabilizers. In addition, while adjacent pairs of engagement assemblies are shown a greater number of corresponding 6 assemblies is contemplated.
7 Referring to FIG. 1, a schematic diagram of the injector 100 is shown 8 according to the present invention. The injector 100 includes two endless 9 tracks 102 and 104, each consisting of like components. The track 102 includes a transport mechanism comprising a rotary input device (not shown), 11 such as an electric or hydraulic motor, which is connected to the drive shaft 12 113 of a drive wheel or sprocket 115. A chain 116 is driven by the drive 13 sprocket 115 and passes over an idler wheel or sprocket 114. The chain 116 is 14 also connected to a plurality of assemblies 112. The assemblies travel with the chain 116 on a continuous path defined by the placement of the drive sprocket 16 115 and the idler sprocket 114. The direction of this path 118 is counter 17 clockwise for sprocket 115.
1 g The track 104 is arranged similarly to that just described, including 19 wheels or sprockets 124 and 125, chain 126, and assemblies 122, and is placed ZO adjacent to the first track 102 and is oriented so that it is in register with the 21 first track. The direction of the path 128 for the sprocket 125 is clockwise.
22 Both tracks 102 and 104 are mounted in a conventional injector frame 23 (not shown) to provide structural support and to maintain proper alignment of 24 the tracks.
With the tracks 102 and 104 traveling in opposing rotary directions and 26 being adjacent and planar with one another, the assemblies 112 and 122 come 27 in contact with each other and interlock at a connecting point 106, which is WO 00!08296 PCT/US99/16149 1 defined by the placement of opposing idler sprockets 114 and 124. The 2 assemblies 112 and 122 form a lateral latched connection 140 which can be 3 seen in greater detail in FIG. 2A. Still referring to FIG. 1, the lateral latched 4 connection is formed and remains while the engagement assemblies are traveling within the zone in between the connecting point 106 and the release 6 point 108. The release point 108 is defined by the placement of the opposing 7 drive sprockets 115 and 125. Within this zone, which shall be referred to as 8 the gripping zone, the lateral latched connection 140 allows for the passage of 9 and engagement with the tubing 110. By engaging and gripping the tubing 110, the assemblies move the tubing in the desired feed direction 138 as the 11 transport mechanism moves the assemblies.
12 Referring to FIGS. 2A-2B, gripping members are housed in the 13 corresponding pair of engagement assemblies 112 and 122. A gripping 14 member I32 is placed so that it is releasably moved into pressurized engagement with the continuous tubing 110. The pressure for the gripping 16 element is supplied by a lateral latch 129, such as a spring 130, which is placed 17 between the assembly 112 and the gripping member 132. The gripping member 18 132 is made of material at its engagement surface having properties to produce 19 a substantial frictional force between the gripping element 132 and the tubing 110 so as to prevent slippage between the two surfaces while avoiding any 21 damage to the continuous tubing 110. The gripping members 132 are shaped 22 so as to substantially maintain contact at points around the entire outer 23 diameter of the tubing 110 when the lateral latched connection 140 is formed.
24 As shown in FIG. 3B, the lateral latch 129 further includes a pair of faces, one face 150 on the gripping member 132 opposite the tubing 110 and a 26 corresponding and engaging face 151 on the engagement assembly. One or 27 both of these faces are inclined laterally inwardly relative to the longitudinal 1 axis of the tubing toward the release point 108. The corresponding pair of 2 gripping members thus act together as slips to mechanically hold the tubing 3 against slippage in the injector toward the release point 108. The spring 4 cooperates with the inclined faces to create su~cient friction on the gripping member for movement along the inclined faces. Alternatively, the lateral drive 6 may comprise an expansible chamber receiving fluid under pressure, a magnetic 7 or a electro-mechanical device. The gripping member 132 may also comprise a 8 liner 152 removably secured to the remainder of the gripping member, with the 9 liner being of a suitable material softer than the tubing while presenting a high coefficient of friction.
11 FIG. 3A shows a cross section of a lateral latched connection 140 12 which is either just forming in conjunction the connecting point 106 or just 13 releasing in conjunction with the release point 108. In this position, the latches 14 are not yet fully engaged. At the connecting point 106, the two idler sprockets 114 and 124 are spaced so as to apply a force on engagement assemblies 112 16 and 122. This force compresses the springs 130 in each block and allows for a 17 close, but slidable, fit between the two assemblies 112 and I22 as they rotate 18 into each other and form a lateral latched connection 140 at the connecting 19 point 106.
More particularly, the engagement assemblies each comprise a lateral 21 latch shown generally at 160 for releasably locking adjacent corresponding 22 engagement assemblies together. The lateral latch 160 may comprise a 23 mechanical latch constituting a projection/recess 161 on one assembly and a 24 corresponding projection/recess 161 on the other assembly. Alternatively, the latch 160 may be a suitable electro-mechanical or magnetic device. The 26 engagement assembly may further comprise longitudinal latches 162 at the ends 1 of each assembly for securing them to adjacent assemblies on their respective 2 tracks, 102, 104.
3 When the laterally latched assemblies move from the connecting point 4 106 and into the gripping zone, the force which was applied by the sprockets S 114 and 124 is no longer present. The lateral drive and gripping members now 6 push the two assemblies 112 and 122 away from each other, thus effecting the 7 interlocking lateral latch as seen in FIG. 3A. While in the gripping zone, a 8 string of assemblies in laterally latched relationship 140 work together to 9 provide the necessary frictional force to move the continuous tubing 110 in the desired feed direction 138.
11 As the assemblies proceed to the release point 108, the two drive 12 sprockets 115 and 125 are spaced so as to again enable the two assemblies 13 and 122 and to disengage at their lateral latches 160. The two assemblies then 14 rotate out of contact and away from each other around their respective drive I S sprockets 115 and 125. The assemblies 112 and 122 then travel with their 16 respective chains 116 and 126 until they arrive at connecting point 106 to once 17 again form a lateral latch 140.
19 ectively, the feed direction 138 of the tubing 110 would also be reversed, thus alto ' movement of the tubing both toward and away from the oilfield Z 1 destination.
22 FIG. 4 shows the ration of the injector via the sequence of 23 relationships of the corresponding en ement assemblies 112, 122 as they 24 move toward, through and away from the grip ' zone to move the tubing.
As shown at A in FIG. 4, the assemblies are first po ' ' ned opposite the 26 tubing 110. Then the lateral latch 129 is actuated to releasably ure the _._ _ .. ._ .. . . ._ _ _ . . _ ._. . . . . _" _ _ _ _ ~" . "° . ~ ~ ~
'!vb ~5 ! V-~ +4J f3;j '? 39:#4.Gu : N t;
_ __ , __ __ __ .__ 1 ~~-09-2000 U S 009916149 I By revcrsin$ the drive directions 118 and 1Z8 of the tracks lOZ and 104 2 respectively, the feed direction 138 of the tubing 110 would also be reversed, thus 3 allowing moveruent of the tubing both toward and away from the oilficld destination.
4 F'IG. :t shows the operation of the inj actor via the sequence of relationships of the corresponding cngagexnent assemblies L 12,1 ZZ as they move toward, through and away 6 from the gripping zone to move the tubing. As shown at A in FIG. 4, the assemblies are 7 fast positioned opposite the tubing 110. Thda the lateral larch 129 is actuated to 8 releasably secure the assemblies together, see position S in FTG. 4.
Thereafter, as shown 9 at positions C and D, the grippinng members arc moved laterally inward into engagement with the tubing X10 and held in engagement therewidz while the asscmbliGS are moved 1 I toward the release point 108. At the release point, the gzippi~g members 132 move 12 laterally away from the tubing, see position E. Lastly, the lateral latches 129 are released 13 and the assemblies part, seepositioa F. Throughout the gripping zone, the gripping force 14 is generated internally of the engagement assembly, thereby eliminating the need for external lateral force which causes wear and reduces reliability.
16 The foregoing description is directed to particular cmbodinnents of the present 17 invention for the puzpose of illustration and explanation. It will be apparent; however, 18 to one skilled in the art tact many modifications and changes to the embodiment set I9 forth above arc possible without departing from the invention as dctermened by the appending claims.

CA 02337500 2001-O1-15 .~. _ . ,_ . _.
AMENDED SHEET

Claims

WHAT IS CLAIMED IS:

1. An injector (100) for moving oilfield tubing (101) relative to an oilfield destination that includes:
a set of endless tracks (102,104) having an opening therebetween for allowing the passage of the tubing therethrough a plurality of engagement assemblies (112,122) carried by each said track, each said engagement assembly on each said track having at least one corresponding assembly on another track, characterized in that:
the corresponding engagement assemblies including interlocking mechanisms (161) which interlock with each other as such engagement assemblies enter a gripping zone (106-108) and move the tubing (110) and unlock as such engagement assemblies leave the gripping zone; and a gripping member (132) which can be selectively moved into pressure engagement with the tubing moveably mounted in each said engagement (112, 122) assembly for gripping the tubing when said corresponding engagement assemblies are interlocked (140) for moving said tubing, and for releasing said tubing when said corresponding engagement assemblies are unlocked, with the gripping force applied by said gripping member (132) on the tubing being generated internally within the corresponding assemblies.

2. The injector of claim 1 further comprising a transport mechanism ( ) to move said engagement assemblies (112,122) along their respective tracks and thus to move the tubing.

3. The injector of claim 1, wherein said gripping member (132) is mounted in its respective assembly for lateral movement toward and away from the tubing and having an inner face (150) extending generally parallel to the longitudinal axis of the outer surface of the tubing, and each engagement assembly further comprises a lateral drive ( ) moving said gripping member laterally into pressurized engagement with the tubing.

4. The injector of claim 1 further comprising a lateral latch (160) releasably locking adjacent corresponding engagement assemblies.

5. The injector of claim 4 wherein the lateral latch is from a group of latch devices consisting of mechanical latch having corresponding projections and recesses (161) releasably locking the assemblies together, electro-mechanical latches and magnetic latches.

6. The injector of claim 1 wherein the face of the gripping member engaging the tubing (110) is of a material softer than the tubing.

7. The injector of claim 3 wherein the lateral drive comprises an expansible chamber receiving fluid under pressure.

8. The injector of claim 3 wherein the lateral drive comprises an electro-mechanical device ( ).

9. The injector of claim 3 wherein said lateral drive comprises said gripping member slideably mounted on a second backing element, with at least one of the elements presenting an inclined face relative to the tubing.

14. The injector of claim 3 whtrein said gripping member and said lateral drive are sized and positioned within their respective engagement assemblies to grip tubing of different diameters.

11. The injector of claim 3 wherein sand gripping member and said lateral drive are sized and positioned within their respective engagement assemblies to grip upsets on the outer diameter of the tubing.