Apparatus and method for removing gelled drilling fluid and filter cake from the side of a well bore

Claim 3

The apparatus of claim 1, further comprising limiting means for limiting the movement of said valve means.

Claim 4

The apparatus of claim 2, wherein said limiting means comprises a shoulder extending radially inwardly into said central opening, wherein said shoulder holds said valve means in said second position.

Claim 5

The apparatus of claim 1, wherein said valve means comprises an opening sleeve having a collet defined on an upper end thereof, and wherein said collet engages a groove defined on said housing thereby releasably attaching said shoulder in said first position.

Claim 6

The apparatus of claim 1, wherein said valve means can be alternated between said first and second positions, so that said valve means can be moved from said second position to and releasably attached in said first position in said central opening.

Claim 7

The apparatus of claim 1, wherein said plurality of diverter ports comprises: a first set of diverter ports, wherein said set of diverter ports is comprised of at least two diverter ports, said exit openings of said diverter ports in said set being located the same vertical distance from an upper end of said housing.

Claim 8

The apparatus of claim 6, wherein said plurality of diverter ports further comprises a second set of diverter ports, said second set of diverter ports being spaced vertically downward from said first set of diverter ports.

Claim 9

The apparatus of claim 7, further comprising jetting nozzles received in said exit openings of said diverter ports, wherein said diverter ports comprise jetting ports so that said apparatus comprises a jetting sub.

Claim 10

The apparatus of claim 1, wherein said exit openings are spaced vertically from said entrance openings.

Claim 11

The apparatus of claim 9, wherein said exit openings of said diverter ports are spaced vertically upward from said entrance openings so that said fluid communicated down said central opening and into said diverter ports is redirected in an upward direction as said fluid passes through said ports.

Claim 12

The apparatus of claim 10, further comprising jetting nozzles received in said exit openings of said diverter ports, wherein said diverter ports comprise jetting ports so that said apparatus comprises a jetting sub.

Claim 13

The apparatus of claim 1, wherein said longitudinal central axis of each of said diverter ports lies in a plane offset from and parallel to a plane defined by said longitudinal central axis of said central opening and a radial axis of said central opening.

Claim 14

The apparatus of claim 12, wherein said longitudinal central axis of said diverter port is parallel to said radial axis of said central bore.

Claim 15

The apparatus of claim 1, wherein each of said diverter ports has a long side and a short side, said long side defining a line tangent to said central opening.

Claim 16

The apparatus of claim 1, further comprising a jetting nozzle received in each diverter port wherein said plurality of diverter ports comprises a plurality of jetting ports, so that said apparatus comprises a jetting sub for removing gelled mud, filter cake and other debris from equipment used in the drilling of offshore wells.

Claim 17

The jetting sub of claim 15, wherein said valve means can be alternated between said first and second positions, so that said valve means can be moved from said second position to and releasably attached in said first position.

Claim 18

A diverter tool for removing gelled drilling fluid and filter cake from a side of a well bore, said diverter tool comprising: a drill string diverter sub disposed in a drill string, said drill string having a drill bit at a lower end thereof, said drill string diverter sub comprising: a housing having a central opening defined therethrough, said central opening being in communication with a central bore of said drill string so that fluid displaced downward through said drill string is communicated to said central opening; a plurality of diverter ports defined through said housing communicating said central opening with a well annulus defined by said drill string and said side of said well bore, wherein each of said diverter ports has a longitudinal central axis and wherein said longitudinal central axis of each of said diverter ports lies in a plane parallel to and offset from a plane defined by a longitudinal central axis and a radial axis of said central opening; and an opening sleeve slidably disposed in said central opening, wherein said sleeve may be alternated between a first position wherein said opening sleeve prevents communication between said diverter ports and said central opening and a second position wherein said diverter ports and said central opening are in communication, flow through said drill string below said diverter ports being blocked when said opening sleeve is in said second position, so that when said opening sleeve is in said second position fluid displaced through said drill string is communicated from said central opening through said diverter ports and is directed into said annulus and into the side of said well bore, thereby removing gelled fluid and filter cake therefrom.

Claim 19

A diverter tool for removing gelled drilling fluid and filter cake from a side of a well bore, said diverter tool comprising: a drill string diverter sub disposed in a drill string, said drill string having a drill bit at a lower end thereof, said drill string diverter sub comprising: a housing having a central opening defined therethrough, said central opening being in communication with a central bore of said drill string so that fluid displaced downward through said drill string is communicated to said central opening; a plurality of diverter ports defined through said housing communicating said central opening with a well annulus defined by said drill string and said side of said well bore, wherein each of said diverter ports has a longitudinal central axis and wherein said longitudinal central axis of each of said diverter ports lies in a plane parallel to and offset from a plane defined by a longitudinal central axis and a radial axis of said central opening; and an opening sleeve slidably disposed in said central opening, wherein said sleeve may be alternated between a first position wherein said opening sleeve prevents communication between said diverter ports and said central opening and a second position wherein said diverter ports and said central opening are in communication, flow through said drill string below said diverter ports being blocked when said opening sleeve is in said second position, so that when said opening sleeve is in said second position fluid displaced through said drill string is communicated from said central opening through said diverter ports and is directed into said annulus and into the side of said well bore, thereby removing gelled fluid and filter cake therefrom.

Claim 20

The tool of claim 17, wherein each said diverter port includes an exit opening defined on an outer surface of said diverter sub and an entrance opening defined at said central opening of said sub, said exit opening being spaced vertically from said entrance opening.

Claim 21

The tool of claim 18, wherein said exit opening is spaced vertically upward from said entrance opening so that fluid displaced down said drill string is redirected upward into said well annulus by said diverter ports when said opening sleeve is in its second position.

Claim 22

The tool of claim 18, further comprising a jetting nozzle received in each of said diverter ports, said diverter tool thereby comprising a jetting tool for removing gelled mud, filter cake and other debris from subsea assemblies and riser pipe used during the drilling of offshore wells.

Claim 23

The tool of claim 17, wherein said diverter ports include an entrance opening defined on said central opening of said housing and an exit opening defined on an outer surface of said housing, said plurality of diverter ports comprising a first set of diverter ports, said set of diverter ports comprising at least two diverter ports having exit openings spaced vertically downward the same distance from an upper end of said housing.

Claim 24

The tool of claim 21, wherein said set of diverter ports comprises four diverter ports defined through said housing.

Claim 25

The tool of claim 22, further comprising a jetting nozzle received in each of said diverter ports, said diverter tool thereby comprising a jetting tool for removing gelled mud, filter cake and other debris from subsea assemblies and riser pipe used during the drilling of offshore wells.

Claim 26

The tool of claim 21, wherein said exit openings are equally spaced radially around the outer surface of said housing.

Claim 27

The tool of claim 21, wherein said plurality of diverter ports further comprises a second set of diverter ports, said exit openings of said second set of diverter ports being spaced vertically downward from said exit openings of said first set of diverter ports.

Claim 28

The tool of claim 25, wherein said exit opening of each diverter port is spaced vertically from said entrance opening of said diverter port.

Claim 29

The tool of claim 26, further comprising a jetting nozzle received in each of said diverter ports, said diverter tool thereby comprising a jetting tool for removing gelled mud, filter cake and other debris from subsea assemblies and riser pipe used during the drilling of offshore wells.

Claim 30

The tool of claim 25, wherein each of said diverter ports has a longitudinal central axis and wherein said longitudinal central axis of each of said diverter ports lies in a plane parallel to and offset from a plane defined by a longitudinal central axis and a radial axis of said central opening.

Claim 31

The tool of claim 17, further comprising a jetting nozzle received in each of said diverter ports, said diverter tool thereby comprising a jetting tool for removing gelled mud, filter cake and other debris from subsea assemblies and riser pipe used during the drilling of offshore wells.

Claim 34

The method of claim 30, wherein said directing step comprises jetting said fluid in an upward direction in said well annulus.

Claim 35

The method of claim 30, wherein said directing step comprises jetting said fluid into said well annulus so that said fluid circulates around said drill string thereby removing gelled mud and filter cake from said well bore.

Claim 36

The method of claim 30, further comprising, between steps (e) and (f) the step of blocking communication through said diverter ports.

Claim 37

The method of claim 30, wherein said step of changing the vertical position of said drill string comprises drilling said well bore to a greater depth.

Claim 40

The method of claim 35, wherein said diverter ports comprise an exit opening and an entrance opening, wherein said exit opening is displaced vertically from said entrance opening, said diverter ports thereby being at an angle such that said streams do not impinge directly on said walls of said well bore.

Claim 41

The method of claim 35, wherein said injecting step comprises: (b)(1) opening said diverter ports, thereby establishing communication between said well bore and a central flow passage of said drill string; (b)(2) obstructing flow through said drill string below said diverter ports.

Claim 42

The method of claim 37, further comprising: (d) removing said obstruction from said drill string so that fluid can flow therethrough to said drill bit; (e) closing said diverter ports thereby preventing communication between said drill string and said annulus through said diverter ports; (f) moving said drill string vertically in said well to a second location; and (g) repeating steps (a)-(c).

Claim 45

The method of claim 39, wherein said equipment comprises a subsea assembly located on the sea floor and a riser pipe connecting said subsea assembly to said offshore drilling platform.

Claim 46

The method of claim 40, wherein said drill string includes a jetting sub attached therein, said jetting sub comprising a plurality of jetting ports, and wherein said jetting step comprises: (b)(1) displacing a fluid down said drill string; (b)(2) opening said jetting ports; (b)(3) obstructing flow through said drill string at a point below said jetting ports; and (b)(4) continuing to displace fluid down said drill string so that said fluid is injected through said jetting ports and into said equipment as said drill string is withdrawn.

Claim 47

The method of claim 41, further comprising: (c) after said drill string has been withdrawn, removing said obstruction from said drill string so that flow can be established therethrough to said drill bit; (d) closing said jetting ports so that communication therethrough is blocked; (e) recommencing drilling operations; and (f) repeating steps (a)-(b).

Claim 48

The method of claim 41, wherein said jetting ports are offset so that said fluid streams create circular flow in the annulus around said drill string.

Claim 51

The apparatus of claim 44, wherein said jetting means includes a jetting nozzle.

Claim 54

The tool of claim 46, wherein said exit opening of each diverter port is spaced vertically from said entrance opening of said diverter port.

Claim 55

The tool of claim 46, wherein each of said diverter ports has a longitudinal central axis and wherein said longitudinal central axis of each of said diverter ports lies in a plane parallel to and offset from a plane defined by a longitudinal central axis and a radial axis of said central opening.

Claim 56

The tool of claim 46, further comprising a jetting nozzle received in each of said diverter ports, said diverter tool thereby comprising a jetting tool for removing gelled mud, filter cake and other debris from subsea assemblies and riser pipe used during the drilling of offshore wells.