Fluid injector for tank cleaning

Information

  • Patent Grant
  • 6588684
  • Patent Number
    6,588,684
  • Date Filed
    Tuesday, October 5, 1999
    25 years ago
  • Date Issued
    Tuesday, July 8, 2003
    21 years ago
Abstract
A fluid injector system for use in tank cleaning is provided, the injector system including an injector head block housing two disc-shaped injectors which may be rotated inside of the injector head block to change the orientation of bores extending through the disc-shaped injectors, which discharge pressurized fluid therethrough. The injector head block depends downwardly from a housing, and is rotatable relative to the housing by rotating a drive tube assembly housed partially within the housing and connected to the injector head block. The disc-shaped injectors are rotated by a vertical movement of the injector head block by virtue of a linkage assembly linking the injectors to a portion of the structure that is vertically stationary when the injector head block is moved vertically.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a fluid injector system for use in cleaning industrial tanks.




Material handling units, such as holding tanks or the like, are used in a wide range of industries, such as the pulp and paper industries, chemical industries, mining and refining industries, and the steel industry. One problem that exists in connection with the use of such holding tanks is that, over time, the liquid in the holding tank can no longer hold the solids suspended therein in solution, and the solids fall out, or are precipitated, and load the bottom of the tank. The settled solids reduce tank capacity, can clog pumps, and, in some instances, lock in valuable capital costs of material.




In order to avoid excessive solids buildup, such industrial tanks must periodically be cleaned. Various tank cleaning methods and devices have heretofore been proposed for use. One such apparatus is disclosed in U.S. Pat. No. 5,253,812. Other techniques have also been used.




Pressure washing of industrial tanks to remove settled sludge from the bottom of the tank has been performed in the past. However, known pressure washing systems have required that the tank be taken offline, or out of service, and drained, in order to expose the sludge for spraying and removal by pressurized fluid. This results in expensive downtime for the tank, presents the problem of where to temporarily store the liquid in the tank (if it has economic value), and presents other scheduling and logistics problems.




The problem to be solved is thus to provide a tank cleaning system that can be used to clean sludge out of the tank without the need to take the tank out of service and/or drain the existing liquid from the tank.




SUMMARY OF THE INVENTION




The present invention is directed to an injector system capable of injecting pressurized fluid into a sludge layer settled in a tank, to break up the sludge into pieces small enough to be pumped out of the tank by a slurry pump or to be removed by other removal equipment. The injector system is capable of being used even when liquid is present in the tank above the surface of the sludge




The injector system includes a housing having an injector head disposed at a lower side thereof, and the housing has a fluid feed tube extending therethrough which supplies a fluid to the injector head from a fluid supply source. The injector head is capable of being rotated through 360° in a horizontal plane, and has two injectors retained therein which can each be rotated through approximately 90°, from pointing in a substantially horizontal orientation, wherein the injectors oppose each other, to pointing in a substantially vertical downward orientation.




The housing of the injector system houses a hydraulic system or subsystem including a hydraulic motor and hydraulic cylinder, that powers the rotation of the injector head and the injectors through various mechanical couplings. The housing may be in either a “stand up” (vertical orientation) or a “lay down” (horizontal orientation) configuration. The injector system is preferably positioned and maneuvered around in the tank by a wire based guidance system of the type disclosed in U.S. Pat. No. 5,526,989.




The injector system is designed to deliver pressurized liquid through the nozzles directed at the sludge layer, to break up the sludge into pieces of a size such that the sludge can be removed by a separate slurry pump or other removal equipment. The pressurized liquid may be water or the liquid present in the tank above the settled sludge, or a combination of the two. Alternatively, a liquid which is soluble with the contents of the tank, may be employed. As an illustrative example, diesel fuel may be used in cleaning an oil tank.











BRIEF DESCRIPTION OF THE DRAWINGS




These and other features of the present invention and the attendant advantages will be readily apparent to those having ordinary skill in the art and the invention will be more easily understood from the following detailed description of the preferred embodiment taken in conjunction with the accompanying drawings wherein like reference characters represent like parts throughout the several views.





FIG. 1

is a cutaway view of a tank illustrating the injector system of the present invention in substantially schematic form.





FIG. 2

is a cross-sectional view of a preferred embodiment of the injector system of the present invention.





FIG. 3

is a side elevation view of the injector head of the injector system illustrated in FIG.


1


.





FIG. 4

is a front elevation view of one-half of the injector head.





FIG. 5

is a front elevation view of an injector according to a preferred embodiment of the present invention.





FIG. 6

is a side elevation view of an injector according to a preferred embodiment of the present invention.





FIG. 7

is a cross-sectional view of an alternative preferred embodiment of the injector system of the present invention.





FIG. 8

is a front elevation view of an alternative preferred embodiment of an injector.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Referring initially to

FIG. 1

, a tank


100


is illustrated in a cutaway, or a substantially schematic cross-section. A layer of settled solids or sludge


102


is shown in the bottom of the tank, and, as is typical, the liquid


104


stored in the tank occupies the space above the sludge. The injector system


10


of the present invention is illustrated in schematic form as being suspended from the roof


106


of the tank


100


by a guidance system


108


using wire, cable or chain, or other suitable material.




The guidance system, termed a positive guidance system


108


, is fully disclosed in U.S. Pat. No. 5,526,989, the disclosure of which is hereby expressly incorporated by reference. The injector can be moved around in the tank


100


, and may be maintained at the desired level, namely riding on the top of the layer of sludge or hovering in close proximity to the top of the sludge, by the positive guidance system. The positive guidance system has the advantage of not requiring a worker to be inside the tank while the tank is being cleaned, and the positive guidance system can be installed without the necessity of emptying the liquid out of the tank. As also noted in the referenced patent, the guidance system also provides the ability to connect the cleaning device, here, the injector system, to the guidance system outside of the tank, and to lower the cleaning device into the tank through a manway or other opening in the roof, to the desired position and height.




The injector system


10


has a sling strap


12


secured at an upper portion of the system housing


14


, with the sling strap


12


connecting to fasteners


110


on the cables of the positive guidance system. The sling strap operates in conjunction with the cables to retain the injector system in a substantially upright or vertical orientation, to the extent practicable.




Turning now to

FIG. 2

, the injector system according to a preferred embodiment is shown in greater detail in the cross-sectional view of that drawing figure. The housing


14


of the injector system may preferably be a length of 12 inch diameter pipe, or a fabricated steel box, or similar housing structure. The housing has a top plate


16


and a bottom plate


18


closing off the upper and lower ends of the housing.




A fluid feed tube


20


, which may preferably be a small diameter pipe capable of withstanding high pressure, extends through an opening


22


in the center of the housing. The fluid feed tube has a fluid tight seal


24


, which seals off the interior of the housing from the external environment.




The fluid feed tube is not rigidly fixed to the housing, but rather may be rotated about the longitudinal axis of the tube and may be moved upwardly and downwardly relative to the housing, along its axial direction. A top bearing


26


disposed in the opening under the seal is secured to the top plate


16


of the housing to facilitate such relative movement.




Bottom plate


18


is affixed at or near the lower extent of the housing


14


, and may preferably be welded in place. Where desired to increase the stability of the housing in an upright position, space is provided underneath bottom plate


18


in the housing for placement of additional weight plates


28


, which may be retained in place by bolts


30


threaded into tapped bores in the bottom plate.




A lower bearing assembly


32


is secured to bottom plate


18


at a central opening in the bottom plate. The additional weight plates


28


have an opening sized to closely surround the outer surface of bearing


32


. Fluid feed tube


20


protrudes downwardly through the inner opening in the bearing


32


, and is threaded onto injector head block


202


of injector head assembly


200


, the details of which will be discussed later in this specification.




Surrounding the fluid feed tube


20


at the region where the tube exits the housing


14


, is a rotary drive tube


34


that forms a fluid-tight seal with the bearing


32


through O-rings


36


, and forms a fluid-tight seal against the outer surface of fluid feed tube


20


through the use of O-rings


38


. Rotary drive tube


34


is secured inside housing


14


to a ring gear drive plate


40


, which has a ring gear


42


fastened thereto by bolts


44


. A hydraulic motor


46


, shown outside housing


14


for the sake of clarity, is mounted to an interior wall of housing


14


by way of mounting bracket


47


in the final assembled unit, and has a drive gear


48


which engages and drives ring gear


42


as desired.




Housing


14


also contains one or more (two shown) two-way hydraulic cylinders


50


, which are preferably secured to the inner surface


52


of top plate


16


. The cylinders are linked to the outwardly extending ears


54


of a trunnion assembly


56


by pins


58


. The trunnion assembly has a bearing assembly


60


at its inner extent, to facilitate relative rotational movement of the fluid feed tube


20


. The trunnion assembly is retained in a fixed axial position relative to the fluid feed tube


20


by upper and lower stop collars


62


,


64


, respectively. As will be discussed in more detail in the discussion of the operation of the injector head and injectors, the piston arms


66


of the hydraulic cylinders may be made to travel upwardly and downwardly through a predetermined range of travel, thereby raising and lowering fluid feed tube


20


along its axial direction.




Housing


14


further has an oil plug


68


threaded into an opening in the side wall of the housing at a position above the gearing, as it is preferred that the lower portion of the housing be filled with oil to lubricate at least the lower internal parts contained in the housing. Housing


14


is further shown as having a hydraulic line


70


extending through the upper plate


16


, and connected to the hydraulic motor and hydraulic cylinders. Hydraulic power for operating the motor and hydraulic cylinders is provided by a hydraulic power system (not shown) that is preferably to be disposed outside the tank.

FIG. 1

shows the hydraulic line entering the tank, and extending down to the injector system


10


.




The injector head assembly


200


of injector system


10


according to a preferred embodiment of the present invention is illustrated in

FIGS. 2-6

. Injector head block


202


is preferably formed of two half-blocks


204


,


206


that are bolted together in the final assembly. The injector head block


202


houses one or more (two shown) injectors


208


, preferably made of thick (approximately 1-2½ inch) steel discs, as best seen in

FIGS. 5 and 6

. The injectors preferably each have a tapered, essentially frustoconical, bore


210


extending through the center thereof, having an orientation defined by a central axis about which the bore is symmetrical, with the central axis preferably extending along a diameter of the disc.




While a tapered bore appears to be preferred for most expected uses, an alternative preferred embodiment, as shown in

FIG. 8

, employs a substantially cylindrical bore


410


which is tapped (i.e., provided with female threading) at one end of the bore. The injector


408


in this embodiment will receive an injector tip


412


having male threads for threadingly engaging the tapped end of bore


410


. Injector tips


412


of varying sizes, shapes, or degrees of internal taper may thus be provided with the unit. The tips may be changed as necessary to have specific tip configurations used for specific types of cleaning jobs.




Referring to

FIG. 4

especially, the manner in which the injectors are retained in the injector head block


202


will be discussed. Each of the half-blocks


204


,


206


are preferably machined, or possibly cast, having mating surfaces


212


at the upper corners and along a portion of the lower edge of the half-blocks. A threaded connection region


214


is formed between the upper corner mating surfaces, although this may preferably be formed by tapping a rough-cut opening after the two half-blocks are assembled into the block. Openings


216


are machined to the same diameter as the diameter of injector discs


208


.




The portion of the half-block that does not form part of the mating surfaces


212


nor the threaded connection region


214


, and that is not fully removed in creating openings


216


, is machined down to approximately one-half of the original block thickness, or by a somewhat greater amount (see, e.g., FIG.


3


). O-ring grooves


218


,


220


are formed in the half-blocks as well, in order to provide a fluid-tight seal between the injector discs


208


and the injector head block


202


. The O-ring grooves may alternatively be placed in the injector disc


208


. It can be seen in

FIG. 4

especially that the area


222


in head block


202


will receive the pressurized fluid from fluid feed tube


20


, and distribute the fluid to the two injectors


208


.




The injector head block is assembled by placing O-rings


224


,


226


, or other suitable seals, in grooves


218


,


220


, in each half-block, positioning the injectors


208


in alignment with their respective openings on each half-block, and then bolting together the two half-blocks to form the injector head block


202


. The assembled head block


202


is threaded onto the lower threaded end


72


of the fluid feed tube


20


. Final connections of the injector head block


202


to the injector assembly


10


are made by securing pivotable link arms


74


to the injectors


208


and to anchors


76


extending downwardly from a drive plate


78


, which itself is threaded onto the lower end of rotary drive tube


34


.




Thus, as the ring gear drive plate


40


is rotatingly driven by the hydraulic motor


46


and ring gear


42


, rotary drive tube and drive plate


34


and


78


, respectively, rotate the entire injector head through a full 360° sweep in a horizontal plane. It should be noted that, as used herein, the term “horizontal” is used as shorthand to describe the orientation of the injector head and drive plate, or an orientation perpendicular to the axis of rotation. If the injector system is tilted in operation, the rotation will obviously not be in a true horizontal plane, but will be in a plane described herein as horizontal. Drive plate


78


is preferably provided with a left-hand thread for its connection to drive tube


34


, whereas vertical fluid shaft


20


is provided with a right-hand thread. This results in a self-tightening connection once all components are assembled, and the connection prevents either threaded unit from coming loose.




This rotation of the injector head in turn causes fluid feed tube to rotate within the housing


14


, and accordingly, along its entire extent. A rotary swivel connector, shown schematically by reference numeral


80


in

FIG. 2

, may preferably be provided at an upper extent of fluid feed tube


20


, to connect the fluid feed tube to a fluid feed line


112


(FIG.


1


), such that the rotary movement is taken up in the connector.




It is presently contemplated that the injector system will be controlled such that the hydraulic motor runs constantly while the unit is in operation, such that the horizontal rotation of the injector head


200


is constant. The orientation of the injector bores may, in addition, be adjusted through preferably nearly 90°, or from pointing essentially along an axis parallel to the fluid feed tube


20


, to pointing along an axis substantially perpendicular to the axis of the fluid feed tube. This is accomplished by the construction and linkages discussed above with respect to, especially,

FIGS. 2 and 3

.




When it is desired to adjust the orientation of the injector bores, the hydraulic cylinders


50


are adjusted to extend or retract the piston arms


66


, as appropriate, which in turn moves trunnion assembly


56


and fluid feed tube


20


upwardly (pistons retracting) or downwardly (pistons extending) relative to housing


14


. Fluid feed tube accordingly moves within the drive tube


34


and pulls (when moving upwardly) or pushes (when moving downwardly) on injector head block


202


. This causes the block to move in response to the force, and causes injectors to rotate about their pivotable linkages, thereby changing the orientation of the bores


210


extending through the injectors.




In the alternative preferred embodiment illustrated in

FIG. 7

, the injector head assembly (not shown in

FIG. 7

, numeral


200


in

FIG. 2

) is preferably identical to that shown in

FIGS. 2-6

. In the

FIG. 7

embodiment, housing


300


is of a flatter, more horizontal, configuration. This embodiment may perform better is some circumstances that the previously discussed embodiment, such as, for example, where the consistency of the sludge to be broken up makes it difficult to maintain the more vertically oriented embodiment of

FIG. 2

in its upright orientation.




Housing


300


is preferably of a short inverted frustoconical or inverted truncated square pyramid shape, having a side wall


302


and a top and bottom plate


304


,


306


, respectively. Fluid feed tube


308


extends through the housing, as in the previous embodiment, having a fluid-tight engagement with top bearing assembly


310


, which facilitates both rotational and axial movement relative to the housing. Fluid feed tube


308


extends outwardly through the lower end of the housing though the interior of rotary drive tube


312


. A lower bearing assembly


314


surrounds the rotary drive tube


312


and is secured to a section of plate


316


that is connected in fluid-tight engagement to the bottom plate


306


of the housing.




The desired rotary motion of the injector head (


200


,

FIG. 2

) secured to the lower end of fluid feed tube


308


is accomplished by a hydraulic motor


318


mounted horizontally within housing


300


by a motor mount bracket


320


secured to the housing


300


. The hydraulic motor drives a beveled drive gear


324


of a bevel gear pair


322


, and driven gear


326


of the gear pair is secured to the upper end of rotary drive tube


312


. Thus, the motor drives the gear pair, which converts the horizontal rotary motion to vertical rotary motion, and the gear pair drives the rotary drive tube, which, as in the previous embodiment, is coupled to the lower drive plate which is linked to the injector head (see FIG.


2


).




The adjustment of the injectors to orient the injector bores as desired is accomplished in the

FIG. 7

embodiment by a linkage assembly that includes a horizontally oriented two-way hydraulic cylinder


330


pivotably anchored to a cylinder brace


332


, which itself is secured to an inner wall of the housing


300


. The piston arm


334


of the cylinder is pivotably connected to an L-shaped arm


336


, which itself is pivotably secured to a lever bracket


338


connected to and extending upwardly from the bottom plate of the housing.




At a distal, or far, end of the L-shaped arm


336


, the arm is retained between upper and lower stop collars


340


,


342


, respectively, with the collars being secured to the fluid supply tube. The L-shaped arm


336


is either forked at its distal end to straddle the fluid supply tube, while still permitting rotation thereof, or a cam follower bracket may be employed. Details of this arrangement are not illustrated, as such connections are well understood in the art.




The fluid supply tube is thus raised or lowered, to bring about the desired reorientation of the injector bores, by controlling the hydraulic cylinder to retract or extend the piston arm, which in turn forces the L-shaped arm pivoting about the pinned connection at lever bracket


338


, to either raise or lower the fluid supply tube. Because the injector head and its connection to the fluid supply tube and drive plate are to be identical to that shown in

FIG. 2

, the action of raising and lowering the fluid supply tube relative to the housing will operate in the same manner to reorient the injector bores.




Thus, by positioning the hydraulic motor and the hydraulic cylinder in a horizontal orientation, the housing


300


can be made to have a shorter profile, which, as noted above, can provide improved operation in certain tank cleaning environments.




By providing a liquid-tight housing containing all parts that might be sensitive to the external environment, the injector assembly of the present invention can be used in a submerged or semi-submerged position relative to liquid contained in a tank to be cleaned. Further, by providing a fluid injector arrangement that has injectors introducing pressurized cleaning fluid though a continuous 360° sweep, and at an orientation relative to the surface of the sludge selected and adjusted to be optimized for the specific conditions found in the tank, a highly efficient approach to breaking up sludge and achieving the optimum fluidization of the material to be cleaned from the tanks is obtained.




The injector assembly may operate to inject liquid at pressures typically in the range of 400-500 psi, at fluid flow rates of about 300-600 gallons per minute. The injector assembly should further be suitable for use at much higher pressures, such as 20,000 psi, if the particular cleaning operation requires the use of higher pressures.




The fluid supply may be an external source of water supplied at 600 psi through fluid supply line


112


, which may be a 2″ hose pressure rated at 800 psi. While this reflects the current pressure levels employed, the fluid injector is expected to be capable of handling operating pressures of 20,000 psi and higher, and the hose used for such applications may preferably be rated at 32,000 psi. The fluid may be pressurized by using a pumping unit equipped with a diesel engine located outside the tank, preferably at the base of the tank. The pump may be set up to use only water, or to use fluid retrieved from, and recirculated to, the tank, or a combination of the two fluids. This is generally determined by the needs of the tank operator, in terms of, for example, the need for higher or lower solids content in the slurry formed by the injector system.




The slurry produced from the sludge and other material broken up by the injector system is generally removed from the tank by a separate system, such as a hydraulically driven slurry pump.




It is also possible to employ more than two injectors on the injector assembly, if desired, although, with the 360° rotation, the additional cost and complexity may not be warranted. Three, four or even more injectors may be disposed in the injector head assembly, preferably being oriented at evenly spaced increments around said injector head. It is further possible to provide two or more injector head assemblies depending downwardly from the housing of the injector system.




It is to be recognized that the foregoing preferred embodiments are depicted and described for illustrative purposes, and the invention is not to be limited only to such embodiments. Various modifications and changes may become apparent to those of ordinary skill in the art upon studying this disclosure, and such modifications and changes do not depart from the spirit and scope of the invention. Accordingly, the scope of the invention herein is to be determined by reference to the appended claims.



Claims
  • 1. A fluid injector system comprising an injector head assembly, said injector head assembly comprising an injector head block retaining at least one injector, each of said one or more injectors having a bore extending therethrough to permit a flow of pressurized fluid therethrough, said at least one injector being housed in said injector head block such that said at least one injector are rotatable relative to said injector head block, said fluid injector system further comprising at least two injectors, and having means for orienting said at least two injectors such that an outlet end of each of said injectors is positioned to discharge liquid in a different direction from, or along a different axis from, the other of the at least two injectors.
  • 2. A fluid injector system as recited in claim 1, wherein said bore extending through each of said at least two injectors is a tapered bore.
  • 3. A fluid injector system as recited in claim 2, wherein said bore extending through each of said at least two injectors is a substantially cylindrical bore.
  • 4. A fluid injector system as recited in claim 3, wherein an outlet end of each of said bores is tapped with female threading.
  • 5. A fluid injector system as recited in claim 4, further comprising at least two injector tips adapted to threadingly engage each of said tapped outlet ends of each of said bores.
  • 6. A fluid injector system as recited in claim 5 further comprising a plurality of sets of injector tips, wherein each set of injector tips has a different configuration, and wherein each of said sets of injector tips is interchangeable with each other set, in being threadingly engageable with said bores of said injectors.
  • 7. A fluid injector system comprising:a housing having an injector head assembly positioned at an underside of said housing, said injector head assembly having means for discharging pressurized fluid through at least one injector to an external environment, a fluid feed tube extending through said housing, from a position above said housing to a position below said housing; said fluid feed tube being fluidly coupled to said injector head assembly at a lower end of said fluid feed tube, whereby said fluid feed tube is operable to supply pressurized fluid to said injector head assembly; said housing having disposed therein a drive means surrounding said fluid feed tube for rotating said injector head assembly relative to said housing, and about an axis of said fluid feed tube, said drive means having a drive tube assembly extending from within said housing to an exterior of said housing, and surrounding said fluid feed tube, said drive tube assembly further being coupled to said injector head assembly, and means for moving said pressurized fluid discharging means such that said at least one injector is moved to discharge fluid at a plurality of angles relative to an axis of rotation of said injector head assembly.
  • 8. A fluid injector system as recited in claim 7, wherein said housing further has, disposed in an interior thereof, a means for moving said fluid feed tube upwardly and downwardly in an axial direction relative to said housing, and relative to said drive tube assembly.
  • 9. A fluid injector system as recited in claim 8, wherein said fluid feed tube moving means comprises at least one hydraulic cylinder.
  • 10. A fluid injector system as recited in claim 7, wherein said drive means for rotating said injector head assembly comprises a hydraulic motor coupled to said drive tube assembly by gear means.
  • 11. A fluid injector system as recited in claim 10, wherein said drive tube assembly comprises a drive tube surrounding said fluid feed tube and extending from an interior of said housing to an exterior of said housing, and a drive plate fixed to said drive tube, and wherein said injector head assembly is coupled to said drive plate by a linkage assembly which permits the injector head assembly to move toward and away from said drive plate.
  • 12. A fluid injector system as recited in claim 11, wherein said injector head assembly comprises an injector head block retaining at least two injectors, said injectors having bores extending therethrough to permit the flow of pressurized fluid therethrough, said injectors being housed in said injector head block such that said injectors are rotatable relative to said injector head block, andwherein said injectors are pivotably linked to said drive tube assembly whereby, upon axial movement of said fluid feed tube by said means for moving said fluid feed tube, said injectors are rotated relative to said injector head block.
  • 13. A fluid injector system as recited in claim 12, wherein said at least two injectors are disc-shaped, and are housed in complementary shaped recesses in said injector head block.
  • 14. A fluid injector system as recited in claim 8, wherein said injector head assembly comprises an injector head block retaining at least two injectors, said injectors having bores extending therethrough to permit the flow of pressurized fluid therethrough, said injectors being housed in said injector head block such that said injectors are rotatable relative to said injector head block, andwherein said injectors are pivotably linked to said drive tube assembly whereby, upon axial movement of said fluid feed tube by said means for moving said fluid feed tube, said injectors are rotated relative to said injector head block.
  • 15. A fluid injector system as recited in claim 14, wherein said at least two injectors are disc-shaped, and are housed in complementary shaped recesses in said injector head block.
  • 16. A fluid injector system as recited in claim 7, wherein said injector head assembly comprises an injector head block retaining at least two injectors, each of said at least two injectors having a bore extending therethrough to permit the flow of pressurized fluid therethorough, said injectors being housed in said injector head block such that said injectors are rotatable relative to said injector head block, and means for orienting said injectors such that an outlet end of each of said injectors is positioned to discharge liquid in a different direction from, or along a different axis from, the other of the said at least two injectors.
  • 17. A fluid injector system as recited in claim 16, wherein said bore extending through each of said at least two injectors is a tapered bore.
  • 18. A fluid injector system as recited in claim 16, wherein said bore extending through each of said at least two injectors is a substantially cylindrical bore.
  • 19. A fluid injector system as recited in claim 18, wherein an outlet end of each of said bores is tapped with female threading.
  • 20. A fluid injector system as recited in claim 19 further comprising at least two injector tips adapted to threadingly engage each of said tapped outlet ends of each of said bores.
Parent Case Info

This application is directed to an invention that has been described and depicted in U.S. Provisional Application Ser. No. 60/112,946, filed Dec. 18, 1998.

US Referenced Citations (6)
Number Name Date Kind
4827680 Rushing et al. May 1989 A
5108035 Friedrichs Apr 1992 A
5217166 Schulze Jun 1993 A
5452853 Shook et al. Sep 1995 A
5454517 Naemura Oct 1995 A
5465777 Brunner Nov 1995 A
Provisional Applications (1)
Number Date Country
60/112946 Dec 1998 US