EP0416915A2 - Time delay perforating apparatus for wells - Google Patents
Time delay perforating apparatus for wells Download PDFInfo
- Publication number
- EP0416915A2 EP0416915A2 EP90309750A EP90309750A EP0416915A2 EP 0416915 A2 EP0416915 A2 EP 0416915A2 EP 90309750 A EP90309750 A EP 90309750A EP 90309750 A EP90309750 A EP 90309750A EP 0416915 A2 EP0416915 A2 EP 0416915A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- time delay
- guns
- housing
- explosive
- gun
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/11—Perforators; Permeators
- E21B43/116—Gun or shaped-charge perforators
- E21B43/1185—Ignition systems
Definitions
- This invention relates to apparatus for perforating a well bore and, more particularly, to an apparatus for firing at least two guns with a predetermined time delay in between.
- Body 56 defines a body central opening 64 therethrough.
- Body central opening 64 includes a first threaded opening 66 adjacent to upper end 60, a first bore 68, a somewhat smaller second bore 70, and a second threaded opening 72 at the lower end of second bore 70.
- a generally annular upwardly facing shoulder 74 extends between first and second bores 68 and 70 in body 56.
Abstract
Description
- This invention relates to apparatus for perforating a well bore and, more particularly, to an apparatus for firing at least two guns with a predetermined time delay in between.
- In well bore perforating operations, it is important for the operator to know whether or not all the guns have been fired. Typically, a time delay device is positioned at the bottom of the string below the lowermost guns. The explosive output of one gun fires the next lower gun, and this continues with the lowermost gun triggering the time delay device. The time delay device has a relatively slow burning material in it, and after this material burns, a small explosive charge in the time delay device is detonated.
- At the surface, the operator can hear and feel the guns firing, and after the guns cease firing, the operator listens for the detonation of the time delay device. If he hears it, he knows all of the guns have fired since the time delay device cannot be actuated otherwise.
- One problem with this prior known apparatus is that, depending upon the depth and conditions of the well, the ignition of the small charge in the time delay device may not be heard. If this is the case, then the operator does not know if the last gun has fired.
- In our U.S. patent specification no. 4,478,294, a time delay device is positioned above the lower one or two guns in the string. The firing of the last gun is thus delayed. The firing of the last gun is significantly louder, and thus more easily discerned, than the detonation of the small charge in the prior art time delay device because the charge in the perforating guns is considerably larger. Electrical sensors may also be provided to monitor the firing of the guns.
- We have now devised an improved apparatus of this type wherein a time delay device is positioned between upper perforating guns and at least the lowermost perforating gun, and wherein a housing is positioned between the guns for receiving the time delay device.
- According to the present invention, there is provided an apparatus for perforating a well bore, said apparatus comprising: an upper gun adapted for connecting to a tool string; housing means for connecting to said upper gun, said housing means defining a housing central opening therethrough; a lower gun connected to said housing means; and a time delay device in said housing means for delaying firing of one of said upper and lower guns for a predetermined period of time after firing of the other of said upper and lower guns.
- Another problem with certain prior art perforating tools is that once some of the guns have fired, fluid is free to enter all of the guns therebelow. If all the guns do not fire, the fluid in the lower guns makes retrieval more difficult. Also, the entire tool must be broken down and drained in order to re-use the lower guns. In a preferred arrangement of the present invention, the time delay device prevents fluid communication between the upper guns and the gun or guns below the time delay device. This allows the time delay device and the guns therebelow to be re-run by simply replacing the portions of the perforating string thereabove. It is not necessary to break down the apparatus and drain it. In fact, the apparatus of the present invention could be run in multiple positions in a perforating string with each location acting as a fluid isolation device to prevent fluid entry into the lower guns in the event of a "stop-fire" (misfire).
- Prior art systems have included fluid isolation shims which perform this function, but the shims are not compatible with all the firing devices and therefore are not usable in all situations.
- The housing means connects the upper and lower perforating guns and houses the time delay device for delaying the firing of one of the guns. The time delay means is characterised in a preferred embodiment by a time delay device disposed in the housing means. The housing means defines a housing central opening therethrough, and the apparatus preferably comprises sealing means for sealing between the time delay means and the housing central opening.
- The time delay device preferably comprises a primer assembly, firing means, such as a firing pin, for impacting and thereby detonating the primer assembly, a time delay mix triggered by detonation of the primer assembly, and explosive means for providing an explosive force which is triggered by the time delay mix. Preferably, an ignition mix is used between the primer assembly and time delay mix. All of these components are positioned in a body central opening defined in a time delay body. The explosive means is a primary explosive ignitable by the delay mix and a secondary explosive ignitable by the primary explosive.
- An upper retainer is preferably engaged with the body for at least partially closing an upper end of the body central opening, and a lower retainer is provided for at least partially closing a lower end of the body central opening. A screen may be disposed between the primer assembly and the delay mix. The firing pin is preferably shearably positioned in the body and has a shearable flange which engages a shoulder in the body. Preferably, a sealing means is provided for sealing between the firing pin and the body central opening.
- In order that the invention may be more fully understood, reference is made to the accompanying drawings, wherein:
- FIG. 1 illustrates one embodiment of perforating apparatus of the present invention in position in a well bore at the end of a tool string;
- FIG. 2 is an enlarged cross-sectional detail of the portion of the tool string which holds the time delay device; and
- FIG. 3 is a longitudinal cross section of an embodiment of time delay device.
- Referring now to the drawings, and more particularly to Fig. 1, the perforating apparatus of the present invention is shown and generally designated by the numeral 10. Apparatus 10 is connected to the lower end of a tool string 12 and is positioned in a well bore 14 which may or may not have a
casing 16. Apparatus 10 is positioned adjacent to aformation 18 to be perforated. - Apparatus 10 includes at least one first or
upper gun 20 and at least one second orlower gun 22. In the preferred embodiment, there will be a plurality ofupper guns 20 and a relatively fewer number oflower guns 22. The invention requires at least one lower gun, but more may be used. Whileguns 20 have been referred to as upper guns, andguns 22 have been referred to as lower guns, it will be understood by those skilled in the art that the guns could be reversed. That is, the firing sequence could be from bottom to top with the uppermost gun being fired after the time delay, rather than fired from top to bottom with the lowermost gun being fired after the time delay. A more detailed description of the firing sequence is provided herein. - Referring now also to FIG. 2, a time delay housing means 24 is disposed between upper and
lower guns elongated housing 24 defining a longitudinal housing central opening 26 therein. - The upper end of
housing 24 is connected to anupper gun 20 at threadedconnection 28. Sealing means, such as O-rings 30, provide sealing engagement between the housing and lower gun. - The lower end of
housing 24 is attached tolower gun 22 at threadedconnection 32 with a sealing means, such as O-rings 34, therebetween. - Housing
central opening 26 includes a first bore 36, a slightly larger second bore 38, and an even larger third bore 40 inhousing 24. A generally annular, downwardly facingshoulder 42 extends between first and second bores 36 and 38, and another generally annular downwardly facingshoulder 44 extends between second bore 38 and third bore 40. A tapped bore 46 extends outwardly away from the lower end of third bore 40. - A
time delay device 50 is positioned incentral opening 26 ofhousing 24 and closes off the housing central opening as best shown in FIG. 2. Sealing means, such as a pair of O-rings 52, provide sealing engagement betweentime delay device 50 and third bore 40 ofhousing 24. A detonation orprimer cord 54 extends downwardly from the explosive portion (not shown) ofupper gun 20 and into contact withtime delay device 50, as will be further discussed herein. - Referring now to FIG. 3, tee details of
time delay device 50 are shown.Time delay device 50 includes anelongated body 56 having anouter surface 58 adapted to fit closely within third bore 40 ofhousing 24. Anupper end 60 ofbody 56 is positioned adjacent toshoulder 44 inhousing 24. A pair ofannular grooves 62 inouter surface 58 receive O-rings 52 therein. -
Body 56 defines a body central opening 64 therethrough. Body central opening 64 includes a first threaded opening 66 adjacent toupper end 60, a first bore 68, a somewhat smaller second bore 70, and a second threaded opening 72 at the lower end of second bore 70. A generally annular upwardly facingshoulder 74 extends between first and second bores 68 and 70 inbody 56. - A firing pin housing 76 is disposed in the upper portion of body central opening 64 in
body 56 and has a threadedportion 78 engaged with threaded opening 66 and alower portion 80 which extends into first bore 68 in close relationship therewith. Sealing means, such as O-rings 82, provide sealing engagement between firing pin housing and first bore 68. - Firing pin housing 76 has a
bore 84 therein with acounterbore 86 at an upper end thereof such that an annular, upwardly facingshoulder 88 is formed. The bottom of firing pin housing 76 has ahole 90 therethrough which is somewhat smaller thanbore 84. - A firing means, such as a
firing pin 92, is disposed in firing pin housing 76. Acentral portion 94 offiring pin 92 fits closely withinbore 84. Sealing means, such as O-rings 96, provide sealing engagement betweenfiring pin 92 and bore 84. It will thus be seen that firing pin housing 76 andfiring pin 92 close off body central opening 64, and it may be generally said that the firing means closes off the body central opening. - At the upper end of firing
pin 92 is ashearable flange 98 which fits incounterbore 86 and rests onshoulder 88 initially. As will be discussed in more detail herein,flange 98 will be sheared when exposed to the explosive output ofgun 20 thereabove. - At the lower end of firing
pin 92 ispin portion 100 which is sized to fit withinhole 90 in firing pin housing 76. - Disposed below firing pin housing 76 in first bore 68 of
body 56 is aprimer assembly 102.Primer assembly 102 is of a kind known in the art and is adapted for detonation upon impact bypin portion 100 of firingpin 92. One such primer assembly comprises titanium potassium perchlorate (TiKClO₄). - A
primer retainer 104 is disposed in first bore 68 ofbody 56 belowprimer assembly 102.Primer retainer 104 defines acentral opening 106 therethrough. - A disc-
like screen 108 having a plurality ofholes 110 therein is positioned betweenprimer retainer 104 andshoulder 74 inbody 56. - Firing pin housing 76, firing
pin 92,primer assembly 102,primer retainer 104 andscreen 108 are clamped in the position shown in FIG. 3 by anupper retainer 112 which has a threadedportion 114 engaged with threaded opening 66 inbody 56.Upper retainer 112 defines acentral opening 116 therein which is adapted for receiving a lower end ofdetonation cord 54. - The present invention includes explosive means disposed in second bore 70 of
body 56 belowscreen 108. The explosive means comprises several components in the preferred embodiment. - Immediately below
screen 108 is an ignition mix ,116, such as an AlA element. - Below
ignition mix 116 is a time delay means 118, such as a time delay mix 118. A tungsten material is used in time delay mix 118 in the preferred embodiment, although the invention is not intended to be limited to tungsten. As is known in the art, the tungsten material is in powdered form, and a small portion is poured into second bore 70 ofbody 56 and compressed to form a tungsten increment 120. Additional tungsten increments 120 are formed in the same way so that a series of such increments are adjacent to one another in second bore 70 as seen in FIG. 3. By varying the quantity of tungsten material and the amount of compression of the powder which affects the density thereof different burn rates of time delay mix 118 are obtained. - Below time delay mix 118 is a primary explosive 122. In the preferred embodiment primary explosive 122 comprises a titanium potassium perchlorate (TiKClO₄) element 124 and a lead azide element 126. Lead azide element 126 is encapsulated in a small cup 128.
- Below primary explosive 122 is a secondary explosive 130 which preferably comprises a PYX charge 132 in an output cup 134. Lead azide element 126 and small cup 128 are also disposed in output cup 128 but are still generally considered part of primary explosive 122 rather than secondary explosive 130.
- A
lower retainer 136, having a threadedportion 138 engaged with second threaded opening 76 inbody 56, holdsignition mix 116, time delay mix 118, primary explosive 122 and secondary explosive 130 in place.Lower retainer 136 defines ahole 140 therein which is in communication withlower gun 22. - After apparatus 10 is positioned as desired in well bore 14,
upper guns 20 are triggered in any manner known in the art, and as also known in the art, sequentially fire one another. The speed of this downward sequence is typically on the order of about 2440m (8000 feet) per second. This is much too fast for the operator to tell how many guns have fired. - When the lowermost one of
guns 20 is fired, it ignitesdetonation cord 54 which provides an explosive force against the upper end of firingpin 92. This force is sufficient to shearflange 98 so that firingpin 92 is moved downwardly untilpin portion 100 thereofimpacts primer assembly 102.Primer assembly 102 is thus detonated and the explosive forces directed downwardly throughcentral opening 106 inprimer retainer 104 and throughholes 110 inscreen 108 to igniteignition mix 116. - The heat from
ignition mix 116 starts the burning of time delay mix 118. The number and density of time delay increments 120 is preselected so that a predetermined period of time is required for time delay mix 118 to completely burn, usually about 10 seconds, although any time may be selected. Once this time has passed, titanium potassium perchlorate element 124 is detonated by the burning of time delay increments 120. The output of element 124 in turn ignites lead azide element 126. Thus, in the preferred embodiment, two components of primary explosive 122 are used. - The explosion from element 126 detonates PYX charge 132 of secondary explosive 130. The explosive output of secondary explosive 130 is directed downwardly through
hole 140 inlower retainer 136 and intolower gun 22. This explosive force from secondary explosive 130 then triggerslower guns 22. The actual ignition oflower guns 22 is known in the art. - Thus, the operator at the surface fires the upper guns which quickly and sequentially fire until
time delay device 50 is actuated. Because of the time delay and burning of time delay elements 120 in time delay means 118, the explosive force necessary to triggerlower guns 22 is thus delayed by the predetermined amount. Whenlower guns 22 do fire, the significant noise and vibration resulting there from is observed by the operator to occur this predetermined time after the firing ofupper guns 20. In this way, the operator knows that all of the guns have fired becauselower guns 22 fired. If all ofupper guns 20 do not fire, thentime delay device 50 is never actuated, and the operator will know that the perforation operation is incomplete because the time delayed firing oflower guns 22 does not occur. As already noted, the tool can be inverted so that the firing sequence is from bottom to top rather than top to bottom. The components described herein would be the same for such an orientation except that each of those components normally would be inverted as well. - Once any of
upper guns 20 are fired, fluid is free to enter the tool string through those guns. All ofupper guns 20 are in fluid communication with one another, and they thus become filled with fluid. However, thetime delay device 50 positioned inhousing 24 blocks any fluid communication betweenupper guns 20 andlower guns 22. In the event of misfire ofupper guns 20,lower guns 22 will not be flooded with fluid. Thus, if the tool string is retrieved, it is only necessary to replace the components abovetime delay device 50. The time delay device and all of the components therebelow may be reused without the necessity of disassembly with cleaning or replacement of parts. This feature of the present invention therefore provides a means of fluid isolation on long gun intervals. - Several of
housings 24 withtime delay devices 50 therein could be positioned along the perforating string to isolate the guns below each time delay device from the guns thereabove. Thus, in addition to the time delay benefits, this fluid isolation benefit saves considerable time in retrieving and refitting a perforating string in which there has been a misfire, and also insures the reuse of components which would otherwise have to be disassembled with some items replaced. - It will be seen, therefore, that the time delay perforating apparatus of the present invention is well adapted to carry out the ends and advantages mentioned as well as those inherent therein. While a presently preferred embodiment of the invention has beef described for the purposes of this disclosure, numerous changes in the arrangement and construction of parts may be mace by those skilled in the art. In particular, but not by way of limitation, different explosive compositions may be used for the various components in addition to the specific compounds cited.
Claims (9)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US40402989A | 1989-09-06 | 1989-09-06 | |
US404029 | 1989-09-06 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0416915A2 true EP0416915A2 (en) | 1991-03-13 |
EP0416915A3 EP0416915A3 (en) | 1992-07-08 |
EP0416915B1 EP0416915B1 (en) | 1995-01-25 |
Family
ID=23597847
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19900309750 Expired - Lifetime EP0416915B1 (en) | 1989-09-06 | 1990-09-06 | Time delay perforating apparatus for wells |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0416915B1 (en) |
JP (1) | JPH03119290A (en) |
CA (1) | CA2024677A1 (en) |
DE (1) | DE69016318T2 (en) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0488519A1 (en) * | 1990-11-21 | 1992-06-03 | Halliburton Company | Downhole perforating tool |
GB2373565A (en) * | 2001-03-08 | 2002-09-25 | Halliburton Energy Serv Inc | Detonation transfer subassembly |
WO2010099480A1 (en) | 2009-02-26 | 2010-09-02 | Owen Oil Tools Lp | Novel device and methods for firing perforating guns |
RU2710342C2 (en) * | 2015-03-18 | 2019-12-25 | Динаэнергетикс Гмбх Унд Ко. Кг | Assembly of detonator head, having rotary electric contact component |
USD904475S1 (en) | 2020-04-29 | 2020-12-08 | DynaEnergetics Europe GmbH | Tandem sub |
USD908754S1 (en) | 2020-04-30 | 2021-01-26 | DynaEnergetics Europe GmbH | Tandem sub |
US11225848B2 (en) | 2020-03-20 | 2022-01-18 | DynaEnergetics Europe GmbH | Tandem seal adapter, adapter assembly with tandem seal adapter, and wellbore tool string with adapter assembly |
US11339614B2 (en) | 2020-03-31 | 2022-05-24 | DynaEnergetics Europe GmbH | Alignment sub and orienting sub adapter |
US11542792B2 (en) | 2013-07-18 | 2023-01-03 | DynaEnergetics Europe GmbH | Tandem seal adapter for use with a wellbore tool, and wellbore tool string including a tandem seal adapter |
US11648513B2 (en) | 2013-07-18 | 2023-05-16 | DynaEnergetics Europe GmbH | Detonator positioning device |
US11713625B2 (en) | 2021-03-03 | 2023-08-01 | DynaEnergetics Europe GmbH | Bulkhead |
US11808093B2 (en) | 2018-07-17 | 2023-11-07 | DynaEnergetics Europe GmbH | Oriented perforating system |
US11906279B2 (en) | 2015-03-18 | 2024-02-20 | DynaEnergetics Europe GmbH | Electrical connector |
US11946728B2 (en) | 2019-12-10 | 2024-04-02 | DynaEnergetics Europe GmbH | Initiator head with circuit board |
US11952872B2 (en) | 2013-07-18 | 2024-04-09 | DynaEnergetics Europe GmbH | Detonator positioning device |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0114103A2 (en) * | 1983-01-20 | 1984-07-25 | Halliburton Company | Positive fire indicator perforating system for wells |
EP0155128B1 (en) * | 1984-03-08 | 1988-08-03 | Halliburton Company | Devices for actuating explosive charges in wellbores, and methods of perforating boreholes |
-
1990
- 1990-09-05 CA CA 2024677 patent/CA2024677A1/en not_active Abandoned
- 1990-09-06 EP EP19900309750 patent/EP0416915B1/en not_active Expired - Lifetime
- 1990-09-06 JP JP23464390A patent/JPH03119290A/en active Pending
- 1990-09-06 DE DE1990616318 patent/DE69016318T2/en not_active Expired - Fee Related
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0114103A2 (en) * | 1983-01-20 | 1984-07-25 | Halliburton Company | Positive fire indicator perforating system for wells |
EP0155128B1 (en) * | 1984-03-08 | 1988-08-03 | Halliburton Company | Devices for actuating explosive charges in wellbores, and methods of perforating boreholes |
Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0488519A1 (en) * | 1990-11-21 | 1992-06-03 | Halliburton Company | Downhole perforating tool |
GB2373565A (en) * | 2001-03-08 | 2002-09-25 | Halliburton Energy Serv Inc | Detonation transfer subassembly |
US6675896B2 (en) | 2001-03-08 | 2004-01-13 | Halliburton Energy Services, Inc. | Detonation transfer subassembly and method for use of same |
GB2373565B (en) * | 2001-03-08 | 2005-02-23 | Halliburton Energy Serv Inc | Detonation transfer subassembly and method for use of the same |
WO2010099480A1 (en) | 2009-02-26 | 2010-09-02 | Owen Oil Tools Lp | Novel device and methods for firing perforating guns |
EP2401474A4 (en) * | 2009-02-26 | 2017-07-19 | Owen Oil Tools LP | Novel device and methods for firing perforating guns |
US11661823B2 (en) | 2013-07-18 | 2023-05-30 | DynaEnergetics Europe GmbH | Perforating gun assembly and wellbore tool string with tandem seal adapter |
US11788389B2 (en) | 2013-07-18 | 2023-10-17 | DynaEnergetics Europe GmbH | Perforating gun assembly having seal element of tandem seal adapter and coupling of housing intersecting with a common plane perpendicular to longitudinal axis |
US11952872B2 (en) | 2013-07-18 | 2024-04-09 | DynaEnergetics Europe GmbH | Detonator positioning device |
US11542792B2 (en) | 2013-07-18 | 2023-01-03 | DynaEnergetics Europe GmbH | Tandem seal adapter for use with a wellbore tool, and wellbore tool string including a tandem seal adapter |
US11608720B2 (en) | 2013-07-18 | 2023-03-21 | DynaEnergetics Europe GmbH | Perforating gun system with electrical connection assemblies |
US11648513B2 (en) | 2013-07-18 | 2023-05-16 | DynaEnergetics Europe GmbH | Detonator positioning device |
US11906279B2 (en) | 2015-03-18 | 2024-02-20 | DynaEnergetics Europe GmbH | Electrical connector |
RU2710342C2 (en) * | 2015-03-18 | 2019-12-25 | Динаэнергетикс Гмбх Унд Ко. Кг | Assembly of detonator head, having rotary electric contact component |
US11808093B2 (en) | 2018-07-17 | 2023-11-07 | DynaEnergetics Europe GmbH | Oriented perforating system |
US11946728B2 (en) | 2019-12-10 | 2024-04-02 | DynaEnergetics Europe GmbH | Initiator head with circuit board |
US11814915B2 (en) | 2020-03-20 | 2023-11-14 | DynaEnergetics Europe GmbH | Adapter assembly for use with a wellbore tool string |
US11225848B2 (en) | 2020-03-20 | 2022-01-18 | DynaEnergetics Europe GmbH | Tandem seal adapter, adapter assembly with tandem seal adapter, and wellbore tool string with adapter assembly |
US11339614B2 (en) | 2020-03-31 | 2022-05-24 | DynaEnergetics Europe GmbH | Alignment sub and orienting sub adapter |
USD904475S1 (en) | 2020-04-29 | 2020-12-08 | DynaEnergetics Europe GmbH | Tandem sub |
USD920402S1 (en) | 2020-04-30 | 2021-05-25 | DynaEnergetics Europe GmbH | Tandem sub |
USD908754S1 (en) | 2020-04-30 | 2021-01-26 | DynaEnergetics Europe GmbH | Tandem sub |
US11713625B2 (en) | 2021-03-03 | 2023-08-01 | DynaEnergetics Europe GmbH | Bulkhead |
Also Published As
Publication number | Publication date |
---|---|
DE69016318D1 (en) | 1995-03-09 |
DE69016318T2 (en) | 1995-05-18 |
CA2024677A1 (en) | 1991-03-07 |
EP0416915B1 (en) | 1995-01-25 |
JPH03119290A (en) | 1991-05-21 |
EP0416915A3 (en) | 1992-07-08 |
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