Title:
Drilling fluid flow facilitation
Kind Code:
A1


Abstract:
A system for facilitating flow of settled solids with drilling fluid from a container, the system including pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, powered rotation apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is movable within the container as fluid is pumped through the at least one nozzle into the container; and, in one aspect, translation apparatus for moving the pressure nozzle apparatus with respect to the container as fluid under pressure is pumped to the at least one rotating nozzle.



Inventors:
Bohnsack, Clyde (Boise, ID, US)
Mcclung III, Guy L. (Spring, TX, US)
Application Number:
12/232420
Publication Date:
01/22/2009
Filing Date:
09/17/2008
Primary Class:
Other Classes:
175/205
International Classes:
E21B21/12
View Patent Images:
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Primary Examiner:
STEPHENSON, DANIEL P
Attorney, Agent or Firm:
WENDEROTH, LIND & PONACK, L.L.P. (1025 Connecticut Avenue, NW Suite 500, Washington, DC, 20036, US)
Claims:
What is claimed is:

1. A system for facilitating flow of drilling fluid from a container of drilling fluid, the drilling fluid containing solids, the system comprising pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the drilling fluid containing solids in the container as fluid is pumped through the at least one nozzle into the container.

2. The system of claim 1 further comprising supply apparatus for supplying fluid under pressure to the pressure nozzle apparatus.

3. The system of claim 1 wherein the container is from the group consisting of mud tank and mud pit.

4. (canceled)

5. The system of claim 1 further comprising control apparatus for selectively controlling the powered rotation apparatus.

6. The system of claim 4 further comprising control apparatus for selectively controlling the powered rotation apparatus, and the control apparatus for selectively controlling the powered translation apparatus.

7. (canceled)

8. The system of claim 7 supply apparatus for supplying fluid under pressure to the pressure nozzle apparatus, and wherein the control system is for receiving signals from the computer system for controlling the supply apparatus in response to said signals so that masses of solids in the drilling fluid are dispersed.

9. The system of claim 1 further comprising the pressure nozzle apparatus for moving settled solids from a floor of a container, pump apparatus for evacuating from the container settled solids moved by the pressure nozzle apparatus, the settled solids evacuatable with drilling fluid, shaker apparatus for receiving and processing the settled solids and drilling fluid pumped by the pump apparatus from the container, the pump apparatus for pumping the settled solids and drilling fluid to the shaker apparatus, and the shaker apparatus for producing a flow of reusable drilling fluid and disposable separated-out solids.

10. A method for facilitating flow of drilling fluid from a container, the method comprising feeding drilling fluid material into a container having a system for facilitating flow of drilling fluid, the system comprising pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, and powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the drilling fluid containing solids in the container as fluid is pumped through the at least one nozzle into the container, the method further comprising dispersing masses of solids within the drilling fluid material by pumping fluid under pressure through the at least one nozzle and rotating the pressure nozzle apparatus with the powered rotation apparatus.

11. 11-15. (canceled)

16. A method for recovering usable drilling fluid from solid masses adjacent a floor of a container, the method comprising moving solid masses adjacent a floor of a container with a moving system, the moving system comprising pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure to move the solid masses, and powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the container to enhance movement of the solid masses as fluid is pumped through the at least one nozzle, the method further comprising rotating the pressure nozzle apparatus with the powered rotation apparatus, and evacuating from the container with pump apparatus drilling fluid and solid masses moved by the moving system.

17. The method of claim 16 further comprising feeding the drilling fluid and solid masses evacuated from the container to shaker apparatus for receiving and processing the drilling fluid and solid masses, and producing with the shaker apparatus a flow of reusable drilling fluid and disposable separated-out solids.

Description:

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to drilling fluid container systems, flow facilitators for such systems, and to methods of their use.

2. Description of Related Art

In drilling operations in the oil industry drilling fluids known as “mud” are circulated down a drillstring, through a bit, and then back out of a wellbore during drilling to remove drilled cuttings and debris from the immediate drilling area. During a drilling operation, the mud is continuously pumped down through the drill string and into the region around the drill bit, picking up drilled cuttings and debris, and then back up a borehole annulus to the surface. Often the mud is made up of clays, chemical additives and an oil or water base and performs several important functions. The mud cools and lubricates the drill bit, carries drill cuttings back up out of the well, and serves to maintain a hydrostatic pressure which prevents pressurized fluids in the earth formation from blowing out through the drilled well.

The mud exiting the wellbore is pumped to a mud pit and then to containers or “mud tanks” in which it resides until it is recirculated down the wellbore. In both the mud pits and in the mud tanks solids in the mud can settle and/or agglomerate forming relatively large masses which are difficult to deal with, which inhibit good flow back into a wellbore, and which can clog pumping and flow equipment.

One effort to deal with these problems employs mud guns which supply fluid, e.g. water, under pressure that is pumped through a nozzle apparatus within a mud container to break up large undesirable solid masses and to facilitate mud flow from the container. In certain systems, the mud gun is manually turned with a handle extending above the mud gun.

SUMMARY OF THE PRESENT INVENTION

The present invention discloses, in certain aspects, methods for recovering usable drilling fluid from solid masses adjacent a floor of a container, the method including: moving solid masses adjacent a floor of a container with a moving system, the moving system having pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure to move the solid masses, and powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the container to enhance movement of the solid masses as fluid is pumped through the at least one nozzle; the method further including rotating the pressure nozzle apparatus with the powered rotation apparatus, and evacuating from the container with pump apparatus drilling fluid and solid masses moved by the moving system.

The present invention discloses, in certain aspects, a system for facilitating the flow of drilling fluid from containers, the system including, in certain aspects, a pressure nozzle apparatus which is rotated by rotation apparatus. In certain particular aspects the pressure nozzle apparatus is rotated automatically. In one aspect, the pressure nozzle is rotated at between 8 and 20 rpm's. In one particular aspect it is rotated at about 12 rpm. Such a system can move settled solids which are then pumped to further processing apparatus (e.g. shaker(s) and/or centrifuge(s)) to re-claim re-usable drilling fluid. Such a system can also facilitate the flow of mud from the container and can enhance the breaking up or dispersion of solid masses so that they are mixed with the mud for efficient re-use.

In one particular aspect, sensors in or adjacent the mud container and/or mud flow lines sense parameters of the mud—e.g., density, composition, or viscosity—and then the sensors signal a control system that activates the rotation apparatus and the pressure nozzle apparatus to jet fluid into the mud to change its parameters thereby facilitating its flow from the container and/or breaking or dispersing solid masses and mixing them with the mud for re-use; or the control system determines that mud composition should be changed. Particular sensors with specified locations are used to effect the jetting of fluid to a specific location in a container.

In certain particular aspects, a pressure nozzle apparatus according to the present invention has one, two, three, four, five or more individual nozzles from which fluid, e.g., water and/or additional drilling fluid, is pumped under pressure. Any nozzle of any system according to the present invention may be directed horizontally within a mud container (e.g., tank or pit), downwardly, or upwardly. In one particular aspect, at least one nozzle is directed downwardly and at least one other nozzle spaced apart from the first nozzle is directed non-downwardly (horizontally or upwardly) so that large solid masses are dispersed or broken and the drilling fluid is mixed homogeneously.

In certain embodiments, the present invention discloses a system in which not only is the pressure nozzle apparatus rotated (e.g., rotated thru an arc or through a whole circle), but it is also translated across a mud container. In one aspect a pressure nozzle apparatus according to the present invention which is rotatable is supported on a support (e.g., a beam or walkway structure) above a mud container with the pressure nozzle apparatus extending down into the mud in the container. The pressure nozzle apparatus is movable with respect to the beam structure across the container or from side to side of the container by suitable movement apparatus, e.g., but not limited to, an endless chain apparatus with a chain than engages a toothed gear on the pressure nozzle apparatus.

The present invention discloses, in certain aspects, systems for facilitating flow of drilling fluid from a container of drilling fluid, the drilling fluid containing solids, the system including: pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, and powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the drilling fluid containing solids in the container as fluid is pumped through the at least one nozzle into the container.

The present invention discloses, in certain aspects, systems for facilitating flow of drilling fluid from a container of drilling fluid, the drilling fluid containing solids, the system including pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, and powered translation apparatus to which the pressure nozzle apparatus is connected, the powered translation apparatus for moving the pressure nozzle apparatus generally with respect to the container.

What follows are some of, but not all, the objects of this invention. In addition to the specific objects stated below for at least certain preferred embodiments of the invention, other objects and purposes will be readily apparent to one of skill in this art who has the benefit of this invention's teachings and disclosures. It is, therefore, an object of at least certain preferred embodiments of the present invention to provide:

New, useful, unique, efficient, nonobvious drilling fluid flow facilitation systems and methods of their use.

New, useful, unique, efficient, nonobvious drilling fluid mixing systems and methods of their use.

Certain embodiments of this invention are not limited to any particular individual feature disclosed here, but include combinations of them distinguished from the prior art in their structures and functions. Features of the invention have been broadly described so that the detailed descriptions that follow may be better understood, and in order that the contributions of this invention to the arts may be better appreciated. There are, of course, additional aspects of the invention described below and which may be included in the subject matter of the claims to this invention. Those skilled in the art who have the benefit of this invention, its teachings, and suggestions will appreciate that the conceptions of this disclosure may be used as a creative basis for designing other structures, methods and systems for carrying out and practicing the present invention. The claims of this invention are to be read to include any legally equivalent devices or methods which do not depart from the spirit and scope of the present invention.

The present invention recognizes and addresses the problems and long-felt needs and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one skilled in this art who has the benefits of this invention's realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent's object to claim this invention no matter how others may later disguise it by variations in form or additions of further improvements.

The Abstract that is part hereof is to enable the U.S. Patent and Trademark Office and the public generally, and scientists, engineers, researchers, and practitioners in the art who are not familiar with patent terms or legal terms of phraseology to determine quickly from a cursory inspection or review the nature and general area of the disclosure of this invention. The Abstract is neither intended to define the invention, which is done by the claims, nor is it intended to be limiting of the scope of the invention in any way.

It will be understood that the various embodiments of the present invention may include one, some, or all of the disclosed, described, and/or enumerated improvements and/or technical advantages and/or elements in claims to this invention.

DESCRIPTION OF THE DRAWINGS

A more particular description of embodiments of the invention briefly summarized above may be had by references to the embodiments which are shown in the drawings which form a part of this specification. These drawings illustrate certain preferred embodiments and are not to be used to improperly limit the scope of the invention which may have other equally effective or legally equivalent embodiments.

FIG. 1 is a schematic view of a system according to the present invention.

FIG. 2A is a schematic top view of a system according to the present invention.

FIG. 2B is a schematic side cross-section view of the system of FIG. 2A.

FIG. 3 is a schematic view of a system according to the present invention.

FIG. 4 is a side view of a rotation system according to the present invention.

FIG. 5 is a top view of the system of FIG. 4.

DESCRIPTION OF EMBODIMENTS PREFERRED AT THE TIME OF FILING FOR THIS PATENT

As shown in FIG. 1 a mud tank 17 and a mud pit 15 each has a system 50 according to the present invention for facilitating mud flow and for mixing solids in the mud with drilling fluid. A drilling rig 11 drills a well 13 into a formation 25. A mud pump 33 pumps mud M in a line 36 into the well 13 down a drillstring 22, to and through a bit apparatus 23, and then up in an annulus 26 to an exit line 27 which feeds into the mud pit 15. The mud M is pumped by a pump 37 in a line 12 into a mud tank 17 from which the mud pump 33 pumps the mud in a line 35 back to the line 36. Each of the systems 50 (either one or which may be deleted) includes a pressure nozzle apparatus 52; a rotation apparatus 54; and a pressure fluid supply apparatus 56. Optionally, either or both systems 50 can include a translation apparatus 58. These apparatuses 52, 53, 54, 56, and 58 are described below.

FIGS. 2A and 2B illustrate schematically a system 100 according to the present invention which has rotation, control, and translation apparatus which can be used with any system according to the present invention. Certain items have been deleted from FIG. 2A which are shown in FIG. 2B.

A container 102 contains drilling fluid or mud 104 in which are entrained solids 106 which are relatively easily pumpable from within the container and relatively larger masses or agglomerations of solids 108 some of which settle on a bottom floor 101 of the container 102.

A pressure nozzle apparatus 110 has a main pipe 112 down which fluid (e.g. water, drilling fluid, water and drilling fluid, and/or any of these with fluid additives) is pumped from a pressurized fluid system 120 in a flexible extendable line 122 which is in fluid communication with the main pipe 112.

A nozzle 114 projects downwardly from the main pipe 112 and fluid under pressure exits the nozzle 114 to impact the solids 106 and the masses 108. Optionally, a second downwardly projecting nozzle 116 is spaced-apart from the nozzle 114 and fluid from the main pipe 112 also exits from the nozzle 116 under pressure. Optionally fluid is also pumped through an upwardly-projecting nozzle 118. Optionally fluid is also pumped through a horizontally-projecting nozzle 119, both nozzles 118 and 119 in fluid communication with the main pipe 112.

Any suitable ratchet system, chain system or translation system may be used to move the system 110 across the container 102. As shown a system 130 has an endless chain 132 which engages a toothed gear 111 on a pipe 113 which is connected to the main pipe 112. Fluid is flowable through the pipe 113. A motor 134 moves the chain 132 thereby moving the system 100 from side to side in the container 102.

Rotation apparatus 140 rotates the main pipe 112.

Sensors 151-155 and 159 within the container 102 and sensor 156 in an input mud line 157 provide signals indicative of mud parameters (e.g. density, composition, viscosity) to a computer system 150 which is in communication with a control system 160 which controls the rotation apparatus 140 and the translation apparatus 130. In response to sensed parameters of the mud in the container, the computer system 150 can direct the control system 160 to maintain or change the speed of rotation of the rotation apparatus 140 or to stop rotation. In response to sensed parameters of the mud in the container the computer system 150 can direct the control system 160 to activate the translation apparatus to move the pressure nozzle apparatus 110 from side-to-side within the container 102 or to a specific location depending on localized fluid parameters within a certain part of the container. In response to sensed parameters of the mud in the container, including its composition, the computer system 150 can provide an alert or warning so that needed additives can be added to the mud.

FIG. 3 shows schematically an alternative embodiment of the system of FIG. 1 and like numerals indicate like parts. The system 50 in the mud tank 17 agitates settled solids 82 on the bottom of the mud tank 17 and a pump system 80 pumps these solids and some drilling fluid in a line 87 to a shaker system 32 (one, two, three, four or more suitable shakers for processing the solids and drilling fluid). Undesirable solids 44 exit from the top of a screen or screens 38 and are collected in a pit 42. Drilling fluid 34 separated from the solids 44, flows to a tank 39 and is then pumped in a line 88 into line 35 for re-use. The tank 39 and/or the pit 42 may have a system according to the present invention, e.g. like the system 50. Instead of or in addition to the shaker system 32, the solids and drilling fluid in the line 87 may be processed by one or more centrifuges.

In one aspect the pump system 80 includes a centrifugal pump and a 60 horsepower motor to run the pump.

FIGS. 4 and 5 show a rotation system 200 according to the present invention for rotating a pressure nozzle apparatus 210 which has a main pipe 212 and a nozzle 220. The system 200 is emplaceable) on a support over a container by positioning a base 202 on a suitable support. The main pipe 212 extends up within a first outer tubular 204 which is connected to the base 202. A second outer tubular 206 encompasses the tubular 204 and has adjustable screws or bolts 208 to adjust the height of the tubular combination, thereby providing height adjustability for the system 200.

The second outer tubular 206 is connected to bracing 214 which supports a plate 216. A motor 218, gear box 222, and a motor starter 224 are connected to the plate 216. A belt 226 driven by the gear box drives a gear 230 connected to the main pipe 212, thereby rotating the main pipe 212. Fluid for jetting (e.g. water, drilling fluid, drilling fluid and water, or any of these plus additives) flows from a pressurized fluid supply source 240, to and through a coupling 232, into a pipe 234 and then into the main pipe 212 from which it exits via the nozzle 220.

Supports 236 connected to the plate 216 support a top member 238 through which the coupling 232 passes.

The main pipe 212 is rotatable through a full 360 degrees continuously.

The present invention, therefore, provides in certain, but not necessarily all embodiments, a system for facilitating flow of drilling fluid from a container of drilling fluid, the drilling fluid containing solids, the system including: pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, and powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the drilling fluid containing solids in the container as fluid is pumped through the at least one nozzle into the container. Such a system may have one or some (in any possible combination) of the following: supply apparatus for supplying fluid under pressure to the pressure nozzle apparatus; wherein the container is a mud tank or a mud pit; powered translation apparatus to which the pressure nozzle apparatus is connected, the powered translation apparatus for moving the pressure nozzle apparatus generally horizontally with respect to the container; control apparatus for selectively controlling the powered rotation apparatus; control apparatus for selectively controlling the powered rotation apparatus, and the control apparatus for selectively controlling the powered translation apparatus; sensor apparatus within the container for sensing at least one parameter of the fluid in the container, and a computer system for receiving signals from the sensor apparatus indicative of the at least one parameter, the computer system for directing the control apparatus; supply apparatus for supplying fluid under pressure to the pressure nozzle apparatus, and wherein the control system is for receiving signals from the computer system for controlling the supply apparatus in response to said signals so that masses of solids in the drilling fluid are dispersed; and/or the pressure nozzle apparatus for moving settled solids from a floor of a container, pump apparatus for evacuating from the container settled solids moved by the pressure nozzle apparatus, the settled solids evacuatable with drilling fluid, shaker apparatus for receiving and processing the settled solids and drilling fluid pumped by the pump apparatus from the container, the pump apparatus for pumping the settled solids and drilling fluid to the shaker apparatus, and the shaker apparatus for producing a flow of re-usable drilling fluid and disposable separated-out solids.

The present invention, therefore, provides in certain, but not necessarily all embodiments, a method for facilitating flow of drilling fluid from a container, the method including: feeding drilling fluid material into a container having a system for facilitating flow of drilling fluid, the system comprising pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, and powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the drilling fluid containing solids in the container as fluid is pumped through the at least one nozzle into the container; the method further including dispersing masses of solids within the drilling fluid material by pumping fluid under pressure through the at least one nozzle and rotating the pressure nozzle apparatus with the powered rotation apparatus; wherein the masses of solids include masses of settled out solids on a floor of the container; wherein the system further comprises sensor apparatus for sensing parameters of the drilling fluid material and for producing signals indicative of measured parameters, the system having a control system including computer apparatus for receiving signals indicative of the measured parameter and for directing the control system in response to said signals, the method further including the computer apparatus directing the control apparatus; and/or wherein the system includes: the pressure nozzle apparatus for moving settled solids from a floor of a container; pump apparatus for evacuating settled solids moved by the pressure nozzle apparatus from the container, the settled solids evacuatable with drilling fluid; shaker apparatus for receiving and processing the settled solids and drilling fluid; the pump apparatus for pumping the settled solids and drilling fluid to the shaker apparatus; and the shaker apparatus for producing a flow of re-usable drilling fluid and disposable separated-out solids; the method further including moving settled solids from the floor of the container; evacuating settled solids with drilling fluid from the container with the pump apparatus; pumping with the pump apparatus the settled solids with drilling fluid to shaker apparatus; and processing with the shaker apparatus the settled solids with drilling fluid, producing reusable drilling fluid and separated-out solids.

The present invention, therefore, provides in certain, but not necessarily all embodiments, a system for facilitating flow of drilling fluid from a container of drilling fluid, the drilling fluid containing solids, the system including pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure, powered translation apparatus to which the pressure nozzle apparatus is connected, the powered translation apparatus for moving the pressure nozzle apparatus generally with respect to the container. Such a system may include powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the drilling fluid containing solids in the container as fluid is pumped through the at least one nozzle into the container.

The present invention, therefore, provides in certain, but not necessarily all embodiments, a method for recovering usable drilling fluid from solid masses adjacent a floor of a container, the method including: moving solid masses adjacent a floor of a container with a moving system, the moving system comprising pressure nozzle apparatus with at least one nozzle from which is flowable fluid under pressure to move the solid masses, and powered rotation apparatus connected to the pressure nozzle apparatus for selectively rotating the pressure nozzle apparatus so that the at least one nozzle is rotatable within the container to enhance movement of the solid masses as fluid is pumped through the at least one nozzle; the method further including rotating the pressure nozzle apparatus with the powered rotation apparatus, and evacuating from the container with pump apparatus drilling fluid and solid masses moved by the moving system. Such a method may include: feeding the drilling fluid and solid masses evacuated from the container to shaker apparatus for receiving and processing the drilling fluid and solid masses; and producing with the shaker apparatus a flow of re-usable drilling fluid and disposable separated-out solids.

In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form it may be utilized. The invention claimed herein is new and novel in accordance with 35 U.S.C. § 102 and satisfies the conditions for patentability in § 102. The invention claimed herein is not obvious in accordance with 35 U.S.C. § 103 and satisfies the conditions for patentability in § 103. This specification and the claims that follow are in accordance with all of the requirements of 35 U.S.C. § 112. The inventors may rely on the Doctrine of Equivalents to determine and assess the scope of their invention and of the claims that follow as they may pertain to apparatus not materially departing from, but outside of, the literal scope of the invention as set forth in the following claims.